WO2019096386A1

WO2019096386A1 - Uplink interference reduction for wireless networks

Info

Publication number: WO2019096386A1
Application number: PCT/EP2017/079425
Authority: WO
Inventors: Jeroen Wigard; István Zsolt KOVÁCS; Huan Cong Nguyen; Rafhael AMORIM
Original assignee: Nokia Technologies Oy
Priority date: 2017-11-16
Filing date: 2017-11-16
Publication date: 2019-05-23

Abstract

A technique for reducing interference may include sending an interference indication message, by a first base station to a second base station, indicating one or more resource blocks and a specific quantity of estimated interference increase at the second base station due to an uplink transmission from a user device that is connected to (or associated with) the first base station.

Description

UPLINK INTERFERENCE REDUCTION FOR WIRELESS NETWORKS

TECHNICAL FIELD

[0001] This description relates to communications.

BACKGROUND

[0002] A communication system may be a facility that enables communication between two or more nodes or devices, such as fixed or mobile communication devices. Signals can be carried on wired or wireless carriers.

[0003] An example of a cellular communication system is an architecture that is being standardized by the 3^rd Generation Partnership Project (3GPP). A recent development in this field is often referred to as the Long Term Evolution (LTE) of the Universal Mobile Telecommunications System (UMTS) radio-access technology.

E-UTRA (evolved UMTS Terrestrial Radio Access) is the air interface of 3GPP's Long Term Evolution (LTE) upgrade path for mobile networks. In LTE, base stations or access points (APs), which are referred to as enhanced Node B (eNBs), provide wireless access within a coverage area or cell. In LTE, mobile devices, or mobile stations are referred to as user equipments (UE). LTE has included a number of improvements or developments.

[0004] 5G New Radio (NR) development is part of a continued mobile broadband evolution process to meet the requirements of 5G, similar to earlier evolution of 3G & 4G wireless networks. A goal of 5G is to provide significant improvement in wireless performance, which may include new levels of data rate, latency, reliability, and security. 5G NR may also scale to efficiently connect the massive Internet of Things (IoT), and may offer new types of mission-critical services. [0005] Uplink inter-cell interference may occur when transmissions from a user device (UE) within one cell cause interference in another cell. Also, for example, downlink inter-cell interference may occur where transmissions from one cell cause interference to the user devices (UEs) in another cell at the same or a different base station.

SUMMARY

[0006] According to an example implementation, a method includes sending an interference indication message, by a first base station to a second base station, indicating one or more resource blocks and a specific quantity of estimated interference increase at the second base station due to an uplink transmission from a user device that is connected to (or associated with) the first base station.

[0007] According to an example implementation, an apparatus includes at least one processor and at least one memory including computer instructions, when executed by the at least one processor, cause the apparatus to: send an interference indication message, by a first base station to a second base station, indicating one or more resource blocks and a specific quantity of estimated interference increase at the second base station due to an uplink transmission from a user device that is connected to (or associated with) the first base station.

[0008] According to an example implementation, a computer program product includes a computer-readable storage medium and storing executable code that, when executed by at least one data processing apparatus, is configured to cause the at least one data processing apparatus to perform a method including: sending an interference indication message, by a first base station to a second base station, indicating one or more resource blocks and a specific quantity of estimated interference increase at the second base station due to an uplink transmission from a user device that is connected to (or associated with) the first base station.

[0009] According to an example implementation, a method includes receiving, by a second base station associated with a second cell from a first base station associated with a first cell, an interference indication message indicating one or more resource blocks and a specific quantity of estimated interference increase at the second base station due to an uplink transmission via the one or more resource blocks from a user device that is connected to the first base station; and sending, by the second base station to the first base station in response to the interference indication message, an interference reduction request message that requests the first base station to reduce an amount of interference increase at the second base station due to an uplink transmission from the user device.

[0010] According to an example implementation, an apparatus includes at least one processor and at least one memory including computer instructions, when executed by the at least one processor, cause the apparatus to: receive, by a second base station associated with a second cell from a first base station associated with a first cell, an interference indication message indicating one or more resource blocks and a specific quantity of estimated interference increase at the second base station due to an uplink transmission via the one or more resource blocks from a user device that is connected to the first base station; and send, by the second base station to the first base station in response to the interference indication message, an interference reduction request message that requests the first base station to reduce an amount of interference increase at the second base station due to an uplink transmission from the user device.

[0011 ] According to an example implementation, a computer program product includes a computer-readable storage medium and storing executable code that, when executed by at least one data processing apparatus, is configured to cause the at least one data processing apparatus to perform a method including: receiving, by a second base station associated with a second cell from a first base station associated with a first cell, an interference indication message indicating one or more resource blocks and a specific quantity of estimated interference increase at the second base station due to an uplink transmission via the one or more resource blocks from a user device that is connected to the first base station; and sending, by the second base station to the first base station in response to the interference indication message, an interference reduction request message that requests the first base station to reduce an amount of interference increase at the second base station due to an uplink transmission from the user device.

[0012] The details of one or more examples of implementations are set forth in the accompanying drawings and the description below. Other features will be apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] FIG. 1 is a block diagram of a wireless network according to an example implementation.

[0014] FIG. 2 is a diagram illustrating uplink interference according to an example implementation.

[0015] FIG. 3 is an example diagram illustrating a relationship between an increase in uplink interference versus a measured downlink signal power according to an example implementation.

[0016] FIG. 4 is a diagram illustrating operation of a system in which inter-cell interference may be reduced according to an example implementation.

[0017] FIG. 5 is a flow chart illustrating operation of a serving/interfering base station according to an example implementation.

[0018] FIG. 6 is a flow chart illustrating operation of a neighbor/victim base station according to an example implementation.

[0019] FIG. 7 is a block diagram of a node or wireless station (e.g., base station/access point or mobile station/user device) according to an example implementation.

DETAIFED DESCRIPTION

[0020] FIG. 1 is a block diagram of a wireless network 130 according to an example implementation. In the wireless network 130 of FIG. 1, user devices 131, 132,

133 and 135, which may also be referred to as mobile stations (MSs) or user equipment (UEs), may be connected (and in communication) with a base station (BS) 134, which may also be referred to as an access point (AP), an enhanced Node B (eNB), a gNB, or a network node. At least part of the functionalities of an access point (AP), base station (BS) or (e)Node B (eNB) may be also be carried out by any node, server or host which may be operably coupled to a transceiver, such as a remote radio head. BS (or AP) 134 provides wireless coverage within a cell 136, including to user devices 131, 132, 133 and 135. Although only four user devices are shown as being connected or attached to BS 134, any number of user devices may be provided. BS 134 is also connected to a core network 150 via a Sl interface 151. This is merely one simple example of a wireless network, and others may be used.

[0021] A user device (user terminal, user equipment (UE) or mobile station) may refer to a portable computing device that includes wireless mobile communication devices operating with or without a subscriber identification module (SIM), including, but not limited to, the following types of devices: a mobile station (MS), a mobile phone, a cell phone, a smartphone, a personal digital assistant (PDA), a handset, a device using a wireless modem (alarm or measurement device, etc.), a laptop and/or touch screen computer, a tablet, a phablet, a game console, a notebook, and a multimedia device, as examples. It should be appreciated that a user device may also be a nearly exclusive uplink only device, of which an example is a camera or video camera loading images or video clips to a network.

[0022] In LTE (as an example), core network 150 may be referred to as

Evolved Packet Core (EPC), which may include a mobility management entity (MME) which may handle or assist with mobility/handover of user devices between BSs, one or more gateways that may forward data and control signals between the BSs and packet data networks or the Internet, and other control functions or blocks.

[0023] In addition, by way of illustrative example, the various example implementations or techniques described herein may be applied to various types of user devices or data service types, or may apply to user devices that may have multiple applications running thereon that may be of different data service types. New Radio (5G) development may support a number of different applications or a number of different data service types, such as for example: machine type communications (MTC), enhanced machine type communication (eMTC), Internet of Things (IoT), and/or narrowband IoT user devices, enhanced mobile broadband (eMBB), wireless relaying including self- backhauling, D2D (device-to-device) communications, and ultra-reliable and low-latency communications (URLLC). Scenarios may cover both traditional licensed band operation as well as unlicensed band operation.

[0024] IoT may refer to an ever-growing group of objects that may have

Internet or network connectivity, so that these objects may send information to and receive information from other network devices. For example, many sensor type applications or devices may monitor a physical condition or a status, and may send a report to a server or other network device, e.g., when an event occurs. Machine Type Communications (MTC, or Machine to Machine communications) may, for example, be characterized by fully automatic data generation, exchange, processing and actuation among intelligent machines, with or without intervention of humans. Enhanced mobile broadband (eMBB) may support much higher data rates than currently available in LTE.

[0025] Ultra-reliable and low-latency communications (URLLC) is a new data service type, or new usage scenario, which may be supported for New Radio (5G) systems. This enables emerging new applications and services, such as industrial automations, autonomous driving, vehicular safety, e-health services, and so on. 3GPP targets in providing connectivity with reliability corresponding to block error rate (BLER) of 10 ⁵ and up to 1 ms U-Plane (user/data plane) latency, by way of illustrative example. Thus, for example, URLLC user devices/UEs may require a significantly lower block error rate than other types of user devices/UEs as well as low latency (with or without requirement for simultaneous high reliability)

[0026] The various example implementations may be applied to a wide variety of wireless technologies or wireless networks, such as LTE, LTE-A, 5G, cmWave, and/or mmWave band networks, IoT, MTC, eMTC, eMBB, URLLC, etc., or any other wireless network or wireless technology. These example networks, technologies or data service types are provided only as illustrative examples.

[0027] FIG. 2 is a diagram illustrating uplink interference according to an example implementation. In this illustrative example, a terrestrial (or land-based) UE 214 may be connected to a serving BS 212 that is providing or associated with a serving cell. A neighbor BS 216 is associated with a neighbor cell. In an illustrative example, uplink transmissions from the UE 214 to the serving BS 212 may also be received by the neighbor BS 216, thus, causing an increase in interference at the neighbor BS 216. Thus, the serving BS 212 may be referred to as an interfering BS, while the neighbor BS may be referred to as a victim BS. For example, an interference increase may be indicated or described as an increase in interference over thermal (IoT) noise , or IoT rise (e.g., a rise in noise over the thermal noise), according to an illustrative example. While there is only one neighbor BS 216/neighbor cell shown in FIG. 2, there may be multiple or many neighbor (or victim) BSs that may experience an increase in interference due to an uplink transmission from the UE 214.

[0028] In addition, as shown in FIG. 2, a UE 218 may be provided on or as part of an aerial vehicle (e.g., unmanned aerial vehicle or drone), which may fly. Similarly, uplink transmissions from UE 218 to serving BS 212 may also cause interference to increase at one or more neighbor BSs, such as by neighbor BS 216. Also, because of the higher altitude of the UAV/UE 218, uplink transmissions from UAV/UE 218 may cause interference to many more neighbor BSs than a terrestrial UE 214. Also, due to the likely higher rate of speed that UAV/UE 218 may be traveling as compared to terrestrial UE 214, the group of BSs that are neighbor (victim) BSs and/or are likely to experience interference from uplink transmissions from UE 218 is likely to change much faster than for terrestrial UE 214. While coordinating and/or reducing inter-cell interference is challenging, inter-cell interference may be especially challenging in an example situation where a UE may have an even greater signal range (e.g., due to the altitude of the UAV UE 218), and thus, cause interference to a larger number of neighbor BSs, and/or in a situation where the group of neighbor BSs that experience an increase in interference based on UE uplink transmissions may change rapidly, such as the case of a UE on an aerial vehicle, for example. These are merely a few illustrative examples of uplink interference that may be experienced by a neighbor B S/neighbor cell, and other examples may be used as well.

[0029] FIG. 3 is an example diagram illustrating a relationship between an increase in uplink interference (e.g., IoT rise) versus a measured downlink signal power according to an example implementation. For example, FIG. 3 may provide an example diagram illustrating a relationship between an increase in uplink interference (e.g., IoT rise) measured by a neighbor BS versus a measured downlink signal power (e.g., reference signal received power or RSRP) of a signal received by a UE from the neighbor BS according to an example implementation. As shown in FIG. 3, a relationship or mapping may be provided or determined, such as based on the experimental data shown in FIG. 3, e.g., that illustrates an example relationship between a IoT caused by an uplink transmission vs. median reference signal received power (RSRP) of downlink

transmissions for both ground (terrestrial) and aerial (e.g., at 100 m height) UEs. Thus, as shown in the illustrative example, generally, an increase in measured downlink RSRP from a neighbor cell corresponds to an increase in IoT rise or interference increase at the neighbor cell. Also, a higher RSRP of received downlink signals from an aerial UE may typically correspond to a higher IoT rise, as compared to terrestrial (ground based) UE. Thus, according to an example implementation, a UE may measure a received power (e.g., RSRP) of reference signals received from each of a multiple neighbor cells, and then report these neighbor RSRP measurements to the serving BS via a measurement report. The serving BS may map each reported received power (or RSRP) to a corresponding or associated interference increase (or IoT rise). According to an example implementation, the measured RSRP of downlink signals received by a UE from a neighbor cell/neighbor BS may provide information regarding a pathloss (or other path information) between the UE and the neighbor BS (including describing the path in the opposite direction from the UE to the neighbor BS). Thus, e.g., based on the chart shown in FIG. 2, or similar information, a serving BS, after receiving a measurement report, may map (e.g., via lookup table or via calculation using a formula) each indicated RSRP provided via a measurement report from the UE to a corresponding interference increase (or IoT rise) that the neighbor cell will likely experience due to an uplink transmission from the UE. Thus, in this illustrative example, a serving BS may determine a corresponding or associated interference increase (e.g., IoT rise) for a neighbor/victim BS based on a measured RSRP (received power) that is reported by the UE to the serving BS.

[0030] According to uplink (UL) High Interference Indication (HII), a report may be provided (e.g., high or low interference) from a source (interfering) cell to all neighbor cells. In HII, the report may typically be sent to all neighbor BSs/cells, e.g., sent to all potential victims. Also, in HII, the report does not indicate which neighbor cell(s) are likely to experience interference, nor how much interference will be experienced. In Interference Overload Indication (OI), a victim cell/BS provides a report on interference overload (high, medium or low) to all neighbor cells. However, in OI, the victim cell has no way of knowing which cell(s) are actually causing the interference, nor is there any way for the victim cell to notify individual cells of specific interference they may be causing. Thus, the HII and OI techniques do not indicate a specific quantity of interference increase (but only some general indicators, such as High, low, medium). Moreover, the HII and 01 techniques do not communicate specific interference increase information from or to a specific interfering BS/cell that is causing the interference. The HII and 01 techniques do not allow identification of an interfering cell. Rather, the source/interfering cells/BSs can only speculate that they may be the source of the reported interference. Also, for HII and/or 01, the neighboring cells may typically be defined statically for a geographic area, and do not accommodate UEs that may have a different range or signal reach (e.g., UAV UEs vs. terrestrial UEs) such as UEs that may have a different numbers of neighbor BSs (e.g., UAV UEs with a greater number of neighbor BSs as compared to traditional terrestrial UEs). Therefore, the HII and 01 techniques are inadequate approaches to reducing inter-cell interference.

[0031] Therefore, according to an example implementation, a technique is provided for reducing interference, including: receiving, by a first (e.g.,

serving/interfering) base station (BS) associated with a first cell from a user device/UE connected to the first BS, a measurement report indicating a received power (e.g., RSRP) for a second (e.g., neighbor/victim) BS associated with a second cell; determining, by the first (e.g., serving/interfering) BS based on the received power for the second

(neighbor/victim) BS, an estimated amount of interference increase (e.g., a 3dB increase, for physical resource blocks/PRBs 1-20) at the second (neighbor/victim) BS due to an uplink transmission from the user device; determining, by the first (e.g.,

serving/interfering) BS, that the estimated amount of interference increase (e.g., 3dB) at the second base station is greater than a threshold (e.g., the 3dB interference increase is greater than a threshold of 2 dB interference increase); and sending an interference indication message, by the first (serving/interfering) BS to the second (e.g.,

neighbor/victim) BS, indicating one or more resource blocks (e.g., indicating PRBs 1-20 to be used for uplink transmission by the UE) and the estimated interference increase (e.g., a 3dB interference increase for PRBs 1-20) at the second (e.g., neighbor/victim) BS due to an uplink transmission from the user device/UE (e.g., due to an uplink

transmission via PRBs 1-20). The technique may also include, for example, receiving, by the first (e.g., serving/interfering) BS from the second (neighbor/victim) BS in response to the interference indication message, an interference reduction request message that requests the first base station to reduce an amount of interference increase at the second base station due to an uplink transmission from the user device, the interference reduction request message indicating one or more resource blocks (e.g.,

PRBs 1-20, or maybe a subset of those indicated PRBs) and a requested interference increase (e.g., a requested interference increase of 1 dB) for one or more resource blocks that is less than the estimated interference increase for the one or more resource blocks.

[0032] Therefore, according to this illustrative example technique, the serving

(e.g., first) BS may determine an estimated amount of interference increase for a neighbor (e.g., second) BS, based on a measurement report from a UE that indicates a received power (e.g., RSRP) of signals received from the neighbor BS. The serving BS may then determine a corresponding estimated amount of interference based on the received power for the neighbor BS. If the estimated amount of interference is greater than a threshold, then the serving BS will notify the neighbor BS of the increase in interference that will be due to its UE, e.g., by sending an interference indication message to the neighbor BS, e.g., indicating one or more resource blocks and a specific quantity of interference increase (e.g., 3dB). If, for example, the neighbor BS determines that the indicated interference increase will negatively impact its ability to deliver a required service quality or quality of service (QoS) to its users/subscribers, then the neighbor BS may send an interference reduction request message to the serving BS, e.g., to request a reduction in the indicated interference increase, e.g., by suggesting only an increase in interference of 2dB, for example. Some further illustrative example implementations will now be described.

[0033] FIG. 4 is a diagram illustrating operation of a system in which inter-cell interference may be reduced according to an example implementation. A UE 414 is connected to a serving BS 410 (serving cell). A plurality of neighbor cells/neighbor BSs may be provided, such as neighbor BS 412. Serving BS 410 may be referred to as an interfering BS/cell due to the UL transmission from its UE 414 that may increase interference at one or more neighbor BSs, such as at neighbor BS 412. Thus, neighbor BS 412 may be referred to as a victim B S/victim cell.

[0034] At 420, UE 414 receives reference signals for one or more neighbor

BSs, and at 422, measures the received power, e.g., RSRP for each neighbor BS, including for neighbor BS 412. At 424, UE 414 sends a measurement report to serving BS 410, including the RSRP/received power of the signals from one or more neighbor BSs, including from neighbor BS 412.

[0035] At 426, the serving BS 410 determines an estimated interference increase (e.g., IoT rise) at the neighbor BS 412 due to an uplink transmission by the UE 414. The RSRP values (measured at 422), received in the measurement report, can be mapped to an interference increase (e.g., IoT rise) in the victim/neighbor BS/cell (see, for example, FIG. 3 for an example relationship between RSRP and interference increase, by way of illustrative example). Also, in an example implementation, for a serving BS 410 to determine a corresponding interference increase, the serving BS 410 may take into account the UE transmission power of the UE (a higher transmission power may typically result in a greater interference increase at the victim BS), and PRB(s)/time-frequency resource blocks used by the UE for uplink transmission. The RSRP of a signal received by UE 414 from neighbor BS 412 may, for example, provide or indicate a channel coupling or pathloss between UE 414 and neighbor cell 412 (e.g., in both directions).

And, UE transmission power will affect the amount of interference increase/IoT rise experienced by neighbor/victim BS 412 due to uplink transmission from interfering UE 414. And, BS 410 may determine which PRB s/time-frequency resource blocks are (or will be) used by UE 414 for uplink transmission, and these PRBs (e.g., PRB indexes) may be identified by serving BS 410. Some PRBs are not used for uplink transmission by UE 414, while other PRBs are used for uplink transmission by UE. Thus, for example, an interference increase or IoT rise is PRB-specific for those PRBs that the UE is transmitting on. (For other PRBs, there is no increase in interference or IoT because UE is not transmitting on such PRBs). A lookup table or equation may be used to determine a interference increase (or IoT rise) corresponding to a specific RSRP, for example.

[0036] At 428, the serving BS 410 may compare the amount of interference increase for neighbor BS 412 to a threshold. In an example implementation, a neighbor BS will be notified of an interference increase due to an uplink UE transmission only if the amount of interference increase is greater than a threshold. The serving BS 410/cell determines if any amount of interference increase (e.g., IoT rise values) (corresponding to UE measured RSRP values in measurement report) are greater than a threshold. [0037] At 430, in the case where the amount of interference increase is greater than the threshold, the serving BS 410 sends an interference indication message (e.g., over X2 interface) to the victim BS/cell (neighbor BS 412), which is now uniquely identified (e.g., based on RSRP of received reference signals from the neighbor BS 412), indicating a specific quantity (e.g., 3dB) of the amount of interference increase and for indicated PRBs (for example, 3 dB interference increase on PRBs 1-20). Also, one or more specific PRBs/time-frequency resource blocks may identified in the interference indication message, e.g., by index number (e.g., PRBs 1, 7, 8 and 12) or range (e.g.,

PRBs 1-20), or a bit map for all PRBs, for which the amount of interference increase applies or is indicated for each PRB. Or, the serving BS may provide top N (where N is an integer), such as a top 5 PRBs where the amount of interference increase is the greatest and exceeds the threshold (e.g., listing/indicating the amount of interference increase for each indicated PRB). Also, in an example implementation, the interference indication message at 430 may also indicate a quality of service (QoS) or QoS parameter for the UE transmission that is the cause of the reported interference increase, e.g., to allow the victim/neighbor BS 412 to weigh or compare these relative QoSs of the interfering UE 414 and its UEs, to determine whether to accept or reject the proposed interference increase.

[0038] At 432, the neighbor/victim BS 412 receives the interference indication message. At 432, the neighbor BS 412 may determine the QoS of traffic/data for its connected UE(s), and may determine if the indicated/proposed amount of interference increase (provided in the received interference indication message) will negatively impact or prevent (e.g., partially or completely) the neighbor BS’s ability to provide the required level of service or QoS to its connected UEs, for example. In other words, the neighbor BS 412 may determine whether or not the proposed amount of interference increase is tolerable/acceptable by the neighbor BS 412. In determining whether or not the proposed interference increase is acceptable/tolerable, the neighbor BS 412, in determining whether it can fulfill the requested QoS of its UEs even with the indicated/proposed interference increase, may consider use of the same PRBs that are indicated in the interference indication message (for which the increased interference has been indicated), as well as possibly using other PRBs (e.g., for which no increased interference has been indicated). If other PRBs are available for its UE traffic, then the neighbor BS 412 may allocate at least some of these other PRBs that are available, to at least some of its UE UL and DL traffic, for example. In such case, where the proposed interference increase it acceptable, the neighbor BS 412 may not send an interference reduction request message at 432 as a reply, or may simply send a confirmation that the proposed interference increase is acceptable.

[0039] In an example implementation, at 432, if the proposed estimated interference increase (received via the interference indication message) is too high (which may negatively impact or at least partially prevent the serving BS’s delivery or providing of requested QoS/service level to its UEs), then at 432, the neighbor BS 412 may determine a reduced amount of interference increase that may be acceptable to the neighbor BS 412. For example, if the serving BS 410 proposes an estimated interference increase of 3 dB at neighbor BS 412 due to the transmission by UE 414, but the highest acceptable (tolerable) interference increase at the neighbor BS 412 is only 2 dB, then the neighbor BS 412 may send, in response to the interference indication message, an interference reduction request message that requests a reduced amount of interference increase at the neighbor BS 412 of only 2 dB due to the uplink transmission from the UE 414, which is less than the estimated/proposed amount of interference increase of 3 dB, for example.

[0040] Also, according to an example implementation, as noted above, the interference indication message at 430 may also indicate a quality of service (QoS) or QoS parameter for the UE transmission that is the cause of the reported interference increase, e.g., to allow the victim/neighbor BS 412 to compare that QoS of the interfering UE 414 to a QoS or required service quality for traffic of its one or more UEs, and to allocate resources accordingly based at least on relative QoS values. For example, the neighbor BS 412 may allow a high amount of interference increase (thus, likely preventing the BS from providing at least some of its required QoS for its UEs) if it is for a higher QoS traffic of the interfering UE 414 as compared to the QoS of its UE’s traffic, for example. And, the neighbor/victim BS 412 may reject such proposed amount of interference increase, e.g., for a same or lower QoS traffic from the interfering UE as compared to its UE QoS requirements. Thus, the relative QoS/service level of the interfering UE and the UEs of the neighbor/victim BS 412 may be considered in determining whether to accept the proposed interference increase or reject that proposed interference increase (e.g., by sending an interference reduction request message at 434, with a reduced amount of interference increase, which may be set to 0 dB to suggest or propose no increase in interference for the indicated PRBs). Alternatively, the neighbor/victim BS may use a threshold, and any proposed interference increase above such threshold may typically be rejected, and a lower amount or reduced amount of interference increase may be suggested.

[0041] At 434, if the neighbor/victim BS 412 would like to at least partially reject the proposed interference request, then the BS 412 may send an interference reduction request to the serving/interfering BS 410, e.g., indicating the reduced amount of interference increase, and an indication of one or more PRBs (e.g., PRB indexes) for which the reduced interference increase applies.

[0042] In addition, at 432, neighbor BS 412 can receive several interference indication messages from different interference sources (e.g., from different interfering BSs). In that case, the neighbor (or victim) BS 412 can calculate the per-PRB (or for each PRB) combined or cumulative effect (cumulative IoT/interference increase, for each or various PRBs) and decide what possible action can be suggested to the different interference sources. If this cumulative increase in interference for one or more PRBs is too much or greater than a threshold, e.g., such that the victim cell is unable to provide its required QoS, then it may send an interference reduction request message (e.g., via X2 interface) at 434 to one or more interfering BSs, requesting those interfering BSs to reduce the interference increase to a specific quantity of interference (e.g., 2 dB) for one or more indicated PRBs. If there are any PRBs indicated in the interference indication message at 430, which are not indicated or mentioned in the interference reduction request message at 134, then the serving BS 410 may assume the proposed interference increase for those omitted or non-mentioned PRBs is acceptable to the neighbor/victim BS 412. For example, in order to reduce the interference increase neighbor BS 412 will experience, the neighbor BS 412 may send a interference reduction request message to each of the interfering BSs; or may send an interference reduction request only to the N greatest/highest interferers (with the highest proposed interference increase), where N is an integer (e.g., top 2 interfering BSs).

[0043] At 436, the serving BS 410 may receive the interference reduction request message, and may determine whether to reduce the transmission power of the UE for those PRBs indicated in the interference reduction request message, e.g., by reducing transmission power or by switching or reallocating different PRBs to the interfering UE 414. Thus, at 436, the serving BS 410 may send to UE 414 a power control command and/or UL scheduling grant to indicate an allocation of resources for UL transmission and control (e.g., decrease) transmission power of the UE, e.g., to at least partially fulfill the requested reduction in interference increase at the neighbor/victim BS 412.

Alternatively, serving BS 410 may reduce interference from transmissions of the interfering UE 414 via use of a partial scheduling arrangement, e.g., by scheduling only a portion of the indicated PRBs (e.g., only schedule half of the indicated PRBs to the interfering UE) or to schedule the interfering UE 414 only some (e.g., every other) transmission time interval (TTI) or subframe, for example.

[0044] At 438, the UE may transmit uplink data via an allocated set of

PRBs/resources, while applying the indicated transmission power, which may reduce interference with the neighbor cell/BS 412 (e.g., via use of different PRBs to reduce interference on the indicated PRBs, or via reduction of transmission power over one or more of the indicated PRBs).

[0045] The reduced amount of interference increase provided in the interference reduction request message may be optionally complied with (e.g., merely suggestive) by BS 410 (e.g., to reduce TX power or use different PRBs for the interfering UE), or it may be necessary to comply with such backoff or interference reduction request. Thus, the interference related quantities may be merely suggestive or proposed, or may be required to implement or comply with, for example.

[0046] Also, rather than providing a general interference increase indicator

(e.g., High, medium or low), the proposed interference increase at 430 and/or the reduced amount of interference increase) may be provided as specific quantities of interference increase or IoT/IoT rise, such as 1 dB, 2dB, 3 dB, 4 dB, ...Using such specific

interference increase quantities, as compared to more general interference indicators (e.g., High, Medium, Low) may provide much more accurate information/instructions between BSs/cells, to allow more effective reduction of inter-cell interference.

[0047] Furthermore, the use of the RSRP for a neighbor BS 412 and mapping or determining a corresponding interference increase or IoT rise for such BS 412 may allow serving/interfering BS 410 to identify one or more specific neighbor/victim BSs/cells that will experience an increase in interference, and to determine a specific amount of interference increase for each victim BS. This may allow a much more effective inter cell interference reduction, and, at least in some cases, may determine or anticipate an expected or future interference increase, and allow the BSs/cells to communicate in order to avoid or at least decrease the identified interference increase.

[0048] Another illustrative example will now be described. A UAV flying at

100 m height, is the only user in its serving cell. It is using maximum power and using all PRBs.

[0049] The serving BS/cell collects RSRP measurements. For the sake of simplicity only 2 cells are reported, victim cell 1 and victim cell 2.

[0050] The serving cell calculates from the RSRP, a transmission power, and

PRBs that the IoT rise in victim cell 1 and victim cell 2 are 6 and 10 dB, respectively.

[0051] As the threshold is set at 3 dB, the serving cell sends an interference indication message indicating 6 and 10 dB of interference increase or noise rise over all PRBs to victim cells 1 and 2.

[0052] Victim cell 1 received the information, but as it is empty (e.g., no traffic to send right now) it does do nothing (no traffic is impacted so no interference mitigation needs to be done. Victim cell 2 has some service ongoing which will be impacted negatively, which can be compensated by allocating more PRBs to this service, but will still see a negative effect. Therefore victim cell 2 sends back to the interference source cell a request to reduce by 3 dB the average interference increase.

[0053] The serving cell lowers the transmission (TX) power of the UAV by 3 dB and thereby halving the IoT impact (e.g., decreasing by half the indicated interference increase).

[0054] Example 1: FIG. 5 is a flow chart illustrating operation of a

serving/interfering base station according to an example implementation. Operation 510 includes sending an interference indication message, by a first base station to a second base station, indicating one or more resource blocks and a specific quantity of estimated interference increase at the second base station due to an uplink transmission from a user device that is connected to the first base station.

[0055] Example 2: According to an example implementation of the method of example 1, wherein the sending comprises: receiving, by the first base station associated with a first cell from the user device connected to the first base station, a measurement report indicating a received power for the second base station associated with a second cell; determining, by the first base station based on the received power for the second base station, a specific quantity of estimated interference increase at the second base station due to an uplink transmission from the user device; determining, by the first base station, that the specific quantity of estimated interference increase at the second base station is greater than a threshold; and sending an interference indication message, by the first base station to the second base station, indicating one or more resource blocks and the specific quantity of estimated interference increase at the second base station due to an uplink transmission from the user device.

[0056] Example 3: According to an example implementation of the method of any of examples 1-2, and further comprising: receiving, by the first base station from the second base station in response to the interference indication message, an interference reduction request message that requests the first base station to reduce an amount of interference increase at the second base station due to an uplink transmission from the user device.

[0057] Example 4: According to an example implementation of the method of any of examples 1-3, and further comprising: receiving, by the first base station from the second base station in response to the interference indication message, an interference reduction request message that requests the first base station to reduce an amount of interference increase at the second base station due to an uplink transmission from the user device, the interference reduction request message indicating one or more resource blocks and a requested reduced amount of interference increase for one or more resource blocks that is less than the specific quantity of estimated interference increase for the one or more resource blocks.

[0058] Example 5: According to an example implementation of the method of any of examples 3-4, wherein the interference reduction request message indicating one or more resource blocks, a requested reduced amount of interference increase for one or more resource blocks that is less than the estimated interference increase for the one or more resource blocks, and a time period for which the requested reduced interference increase is applicable for.

[0059] Example 6: According to an example implementation of the method of any of examples 3-5, and further comprising: sending, by the first base station to the user device based on the requested reduced amount of interference increase, a power control command to cause the user device to adjust its transmission power via the one or more resource blocks.

[0060] Example 7 According to an example implementation of the method of any of examples 1-6, wherein the specific quantity of estimated amount of interference increase at the second base station due to an uplink transmission from the user device comprises: a specific quantity of estimated increase over thermal noise (IoT) rise at the second base station due to an uplink transmission from the user device.

[0061] Example 8: According to an example implementation of the method of any of examples 1-7, wherein the interference indication message comprises: an indication of one or more resource blocks and a specific quantity of estimated

interference increase at the second base station for the one or more resource blocks due to an uplink transmission from the user device via the one or more resource blocks, and a quality of service of the uplink transmission from the user device.

[0062] Example 9: According to an example implementation of the method of any of examples 1-8, wherein the interference indication message comprises: an indication of one or more resource blocks and a resource block- specific quantity of estimated interference increase at the second base station for each of the one or more resource blocks due to an uplink transmission from the user device via the one or more resource blocks, and a quality of service of the uplink transmission from the user device.

[0063] Example 10: According to an example implementation of the method of any of examples 2-9, wherein: the receiving comprises receiving, by a first base station associated with a first cell from a first user device and a second user device, a

measurement report indicating a received power for a second base station associated with a second cell; wherein the determining an estimated amount of interference comprises determining, by the first base station based on the received power for the second base station, a first specific quantity of estimated interference increase at the second base station due to an uplink transmission from the first user device and a second specific quantity of estimated amount of interference increase at the second base station due to an uplink transmission from the second user device; wherein the determining that the specific quantity of estimated interference increase at the second base station is greater than a threshold comprises determining, by the first base station, that the first specific quantity of estimated interference increase at the second base station is greater than a threshold and that the second specific quantity of estimated amount of interference increase at the second base station is less than or equal to the threshold; and wherein the sending comprises sending, based on the first specific quantity of estimated amount of interference increase at the second base station is greater than the threshold, an interference indication message, by the first base station to the second base station, indicating one or more resource blocks and the first specific quantity of estimated interference increase at the second base station due to an uplink transmission from the first user device via the one or more resource blocks, and omitting to send, based on the second specific quantity of estimated amount of interference increase at the second base station that is due to an uplink transmission from the second user device is less than or equal to the threshold, an additional interference indication message, by the first base station to the second base station.

[0064] Example 11 : An apparatus comprising means for performing a method of any of examples 1-10.

[0065] Example 12: An apparatus comprising at least one processor and at least one memory including computer instructions that, when executed by the at least one processor, cause the apparatus to perform a method of any of examples 1-10.

[0066] Example 13: An apparatus comprising a computer program product including a non-transitory computer-readable storage medium and storing executable code that, when executed by at least one data processing apparatus, is configured to cause the at least one data processing apparatus to perform a method of any of examples 1-10.

[0067] Example 14: FIG. 6 is a diagram illustrating a method of reducing interference. Operation 610 includes receiving, by a second base station associated with a second cell from a first base station associated with a first cell, an interference indication message indicating one or more resource blocks and a specific quantity of estimated interference increase at the second base station due to an uplink transmission via the one or more resource blocks from a user device that is connected to the first base station. And, operation 620 includes sending, by the second base station to the first base station in response to the interference indication message, an interference reduction request message that requests the first base station to reduce an amount of interference increase at the second base station due to an uplink transmission from the user device.

[0068] Example 15: According to an example implementation of the method of example 14, wherein the interference reduction request message indicates one or more resource blocks and a requested reduced interference increase for one or more resource blocks that is less than the specific quantity of estimated interference increase for the one or more resource blocks.

[0069] Example 16: According to an example implementation of the method of any of examples 14-15, wherein the estimated amount of interference increase at the second base station due to an uplink transmission from the user device comprises: a specific quantity of estimated increase over thermal noise (IoT) rise at the second base station due to an uplink transmission from the user device.

[0070] Example 17: According to an example implementation of the method of any of examples 14-16, wherein the interference indication message comprises: an indication of one or more resource blocks and a specific quantity of estimated

[0071] Example 18: According to an example implementation of the method of any of examples 14-17, wherein the sending comprises: determining, by the second base station, service requirements for one or more users connected to the second base station; determining, by the second base station, that the specific quantity of estimated interference increase at the second base station will negatively impact the ability of the second base station to meet the service requirements for one or more user devices connected to the second base station; determining, by the second base station, a reduced amount of interference increase at the second base station that is less than the specific quantity of estimated interference increase and will provide less negative impact to the ability of the second base station to meet the service requirements for one or more user devices connected to the second base station; and sending, by the second base station to the first base station in response to the interference indication message, an interference reduction request message indicating the reduced amount of interference increase that is requested by the second base station.

[0072] Example 19: According to an example implementation of example 18, wherein the determining, by the second base station, a reduced amount of interference increase at the second base station considers both a quality of service or service requirements of the uplink transmission via the one or more resource blocks from the user device that is connected to the first base station and the service requirements for one or more users connected to the second base station.

[0073] Example 20: According to an example implementation of the method of any of examples 14-19, wherein: the receiving comprises: receiving, by the second base station associated with a second cell from a first base station associated with a first cell, a first interference indication message indicating a first set of one or more resource blocks and a first specific quantity of estimated interference increase at the second base station due to an uplink transmission via the first set of one or more resource blocks from a user device that is connected to the first base station; receiving, by the second base station from a third base station associated with a third cell, a second interference indication message indicating a second set of one or more resource blocks and a second specific quantity of estimated interference increase at the second base station due to an uplink transmission via the second set of one or more resource blocks from a user device that is connected to the third base station; determining, by the second base station based on the first estimated interference increase and the second estimated interference increase, a first reduced amount of interference increase at the second base station that is less than the first specific quantity of estimated interference increase, and a second reduced amount of interference increase at the second base station that is less than the second specific quantity of estimated interference increase; wherein the sending comprises: sending, by the second base station to the first base station, a first interference reduction request message indicating the first reduced amount of interference increase that is requested by the second base station; and sending, by the second base station to the third base station, a second interference reduction request message indicating the second reduced amount of interference increase that is requested by the second base station.

[0074] Example 21: An apparatus comprising means for performing a method of any of examples 14-20.

[0075] Example 22: An apparatus comprising at least one processor and at least one memory including computer instructions that, when executed by the at least one processor, cause the apparatus to perform a method of any of examples 14-21.

[0076] Example 23: An apparatus comprising a computer program product including a non-transitory computer-readable storage medium and storing executable code that, when executed by at least one data processing apparatus, is configured to cause the at least one data processing apparatus to perform a method of any of examples 14-20.

[0077] FIG. 7 is a block diagram of a wireless station (e.g., AP, BS, relay node, eNB, UE or user device) 1000 according to an example implementation. The wireless station 1000 may include, for example, one or two RF (radio frequency) or wireless transceivers 1002A, 1002B, where each wireless transceiver includes a transmitter to transmit signals and a receiver to receive signals. The wireless station also includes a processor or control unit/entity (controller) 1004 to execute instructions or software and control transmission and receptions of signals, and a memory 1006 to store data and/or instructions.

[0078] Processor 1004 may also make decisions or determinations, generate frames, packets or messages for transmission, decode received frames or messages for further processing, and other tasks or functions described herein. Processor 1004, which may be a baseband processor, for example, may generate messages, packets, frames or other signals for transmission via wireless transceiver 1002 (1002A or 1002B). Processor 1004 may control transmission of signals or messages over a wireless network, and may control the reception of signals or messages, etc., via a wireless network (e.g., after being down-converted by wireless transceiver 1002, for example). Processor 1004 may be programmable and capable of executing software or other instructions stored in memory or on other computer media to perform the various tasks and functions described above, such as one or more of the tasks or methods described above. Processor 1004 may be (or may include), for example, hardware, programmable logic, a programmable processor that executes software or firmware, and/or any combination of these. Using other terminology, processor 1004 and transceiver 1002 together may be considered as a wireless transmitter/receiver system, for example.

[0079] In addition, referring to FIG. 7, a controller (or processor) 1008 may execute software and instructions, and may provide overall control for the station 1000, and may provide control for other systems not shown in FIG. 7, such as controlling input/output devices (e.g., display, keypad), and/or may execute software for one or more applications that may be provided on wireless station 1000, such as, for example, an email program, audio/video applications, a word processor, a Voice over IP application, or other application or software.

[0080] In addition, a storage medium may be provided that includes stored instructions, which when executed by a controller or processor may result in the processor 1004, or other controller or processor, performing one or more of the functions or tasks described above.

[0081 ] According to another example implementation, RF or wireless transceiver(s) 1002A/1002B may receive signals or data and/or transmit or send signals or data. Processor 1004 (and possibly transceivers 1002A/1002B) may control the RF or wireless transceiver 1002A or 1002B to receive, send, broadcast or transmit signals or data.

[0082] The embodiments are not, however, restricted to the system that is given as an example, but a person skilled in the art may apply the solution to other communication systems. Another example of a suitable communications system is the 5G concept. It is assumed that network architecture in 5G will be quite similar to that of the LTE-advanced. 5G is likely to use multiple input - multiple output (MIMO) antennas, many more base stations or nodes than the LTE (a so-called small cell concept), including macro sites operating in co-operation with smaller stations and perhaps also employing a variety of radio technologies for better coverage and enhanced data rates. [0083] It should be appreciated that future networks may utilise network functions virtualization (NFV) which is a network architecture concept that proposes virtualizing network node functions into“building blocks” or entities that may be operationally connected or linked together to provide services. A virtualized network function (VNF) may comprise one or more virtual machines running computer program codes using standard or general type servers instead of customized hardware. Cloud computing or data storage may also be utilized. In radio communications this may mean node operations may be carried out, at least partly, in a server, host or node operationally coupled to a remote radio head. It is also possible that node operations may be distributed among a plurality of servers, nodes or hosts. It should also be understood that the distribution of labour between core network operations and base station operations may differ from that of the LTE or even be non-existent.

[0084] Implementations of the various techniques described herein may be implemented in digital electronic circuitry, or in computer hardware, firmware, software, or in combinations of them. Implementations may implemented as a computer program product, i.e., a computer program tangibly embodied in an information carrier, e.g., in a machine-readable storage device or in a propagated signal, for execution by, or to control the operation of, a data processing apparatus, e.g., a programmable processor, a computer, or multiple computers. Implementations may also be provided on a computer readable medium or computer readable storage medium, which may be a non-transitory medium. Implementations of the various techniques may also include implementations provided via transitory signals or media, and/or programs and/or software

implementations that are downloadable via the Internet or other network(s), either wired networks and/or wireless networks. In addition, implementations may be provided via machine type communications (MTC), and also via an Internet of Things (IOT).

[0085] The computer program may be in source code form, object code form, or in some intermediate form, and it may be stored in some sort of carrier, distribution medium, or computer readable medium, which may be any entity or device capable of carrying the program. Such carriers include a record medium, computer memory, read only memory, photoelectrical and/or electrical carrier signal, telecommunications signal, and software distribution package, for example. Depending on the processing power needed, the computer program may be executed in a single electronic digital computer or it may be distributed amongst a number of computers.

[0086] Furthermore, implementations of the various techniques described herein may use a cyber-physical system (CPS) (a system of collaborating computational elements controlling physical entities). CPS may enable the implementation and exploitation of massive amounts of interconnected ICT devices (sensors, actuators, processors microcontrollers,...) embedded in physical objects at different locations.

Mobile cyber physical systems, in which the physical system in question has inherent mobility, are a subcategory of cyber-physical systems. Examples of mobile physical systems include mobile robotics and electronics transported by humans or animals.

The rise in popularity of smartphones has increased interest in the area of mobile cyber physical systems. Therefore, various implementations of techniques described herein may be provided via one or more of these technologies.

[0087] A computer program, such as the computer program(s) described above, can be written in any form of programming language, including compiled or interpreted languages, and can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit or part of it suitable for use in a computing environment. A computer program can be deployed to be executed on one computer or on multiple computers at one site or distributed across multiple sites and interconnected by a communication network.

[0088] Method steps may be performed by one or more programmable processors executing a computer program or computer program portions to perform functions by operating on input data and generating output. Method steps also may be performed by, and an apparatus may be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit).

[0089] Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer, chip or chipset. Generally, a processor will receive instructions and data from a read-only memory or a random access memory or both. Elements of a computer may include at least one processor for executing instructions and one or more memory devices for storing instructions and data.

Generally, a computer also may include, or be operatively coupled to receive data from or transfer data to, or both, one or more mass storage devices for storing data, e.g., magnetic, magneto-optical disks, or optical disks. Information carriers suitable for embodying computer program instructions and data include all forms of non-volatile memory, including by way of example semiconductor memory devices, e.g., EPROM, EEPROM, and flash memory devices; magnetic disks, e.g., internal hard disks or removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks. The processor and the memory may be supplemented by, or incorporated in, special purpose logic circuitry.

[0090] To provide for interaction with a user, implementations may be implemented on a computer having a display device, e.g., a cathode ray tube (CRT) or liquid crystal display (LCD) monitor, for displaying information to the user and a user interface, such as a keyboard and a pointing device, e.g., a mouse or a trackball, by which the user can provide input to the computer. Other kinds of devices can be used to provide for interaction with a user as well; for example, feedback provided to the user can be any form of sensory feedback, e.g., visual feedback, auditory feedback, or tactile feedback; and input from the user can be received in any form, including acoustic, speech, or tactile input.

[0091 ] Implementations may be implemented in a computing system that includes a back-end component, e.g., as a data server, or that includes a middleware component, e.g., an application server, or that includes a front-end component, e.g., a client computer having a graphical user interface or a Web browser through which a user can interact with an implementation, or any combination of such back-end, middleware, or front-end components. Components may be interconnected by any form or medium of digital data communication, e.g., a communication network. Examples of

communication networks include a local area network (LAN) and a wide area network (WAN), e.g., the Internet.

[0092] While certain features of the described implementations have been illustrated as described herein, many modifications, substitutions, changes and equivalents will now occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the various embodiments.

Claims

WHAT IS CLAIMED IS:

1. A method of reducing interference, comprising:

sending an interference indication message, by a first base station to a second base station, indicating one or more resource blocks and a specific quantity of estimated interference increase at the second base station due to an uplink transmission from a user device that is connected to the first base station.

2. The method of claim 1 wherein the sending comprises:

receiving, by the first base station associated with a first cell from the user device connected to the first base station, a measurement report indicating a received power for the second base station associated with a second cell;

determining, by the first base station based on the received power for the second base station, a specific quantity of estimated interference increase at the second base station due to an uplink transmission from the user device;

determining, by the first base station, that the specific quantity of estimated interference increase at the second base station is greater than a threshold; and

sending an interference indication message, by the first base station to the second base station, indicating one or more resource blocks and the specific quantity of estimated interference increase at the second base station due to an uplink transmission from the user device.

3. The method of any of claims 1-2 and further comprising:

receiving, by the first base station from the second base station in response to the interference indication message, an interference reduction request message that requests the first base station to reduce an amount of interference increase at the second base station due to an uplink transmission from the user device.

4. The method of any of claims 1-3 and further comprising:

receiving, by the first base station from the second base station in response to the interference indication message, an interference reduction request message that requests the first base station to reduce an amount of interference increase at the second base station due to an uplink transmission from the user device, the interference reduction request message indicating one or more resource blocks and a requested reduced amount of interference increase for one or more resource blocks that is less than the specific quantity of estimated interference increase for the one or more resource blocks.

5. The method of any of claims 3-4 wherein the interference reduction request message indicating one or more resource blocks, a requested reduced amount of interference increase for one or more resource blocks that is less than the estimated interference increase for the one or more resource blocks, and a time period for which the requested reduced interference increase is applicable for.

6. The method of any of claims 3-5 and further comprising:

sending, by the first base station to the user device based on the requested reduced amount of interference increase, a power control command to cause the user device to adjust its transmission power via the one or more resource blocks.

7. The method of any of claims 1-6 wherein the specific quantity of estimated amount of interference increase at the second base station due to an uplink transmission from the user device comprises:

a specific quantity of estimated increase over thermal noise (IoT) rise at the second base station due to an uplink transmission from the user device.

8. The method of any of claims 1-7 wherein the interference indication message comprises:

an indication of one or more resource blocks and a specific quantity of estimated interference increase at the second base station for the one or more resource blocks due to an uplink transmission from the user device via the one or more resource blocks, and a quality of service of the uplink transmission from the user device.

9. The method of any of claims 1-8 wherein the interference indication message comprises:

an indication of one or more resource blocks and a resource block- specific quantity of estimated interference increase at the second base station for each of the one or more resource blocks due to an uplink transmission from the user device via the one or more resource blocks, and a quality of service of the uplink transmission from the user device.

10. The method of any of claims 2-9, wherein:

the receiving comprises receiving, by a first base station associated with a first cell from a first user device and a second user device, a measurement report indicating a received power for a second base station associated with a second cell;

wherein the determining an estimated amount of interference comprises determining, by the first base station based on the received power for the second base station, a first specific quantity of estimated interference increase at the second base station due to an uplink transmission from the first user device and a second specific quantity of estimated amount of interference increase at the second base station due to an uplink transmission from the second user device;

wherein the determining that the specific quantity of estimated interference increase at the second base station is greater than a threshold comprises determining, by the first base station, that the first specific quantity of estimated interference increase at the second base station is greater than a threshold and that the second specific quantity of estimated amount of interference increase at the second base station is less than or equal to the threshold; and

wherein the sending comprises sending, based on the first specific quantity of estimated amount of interference increase at the second base station is greater than the threshold, an interference indication message, by the first base station to the second base station, indicating one or more resource blocks and the first specific quantity of estimated interference increase at the second base station due to an uplink transmission from the first user device via the one or more resource blocks, and omitting to send, based on the second specific quantity of estimated amount of interference increase at the second base station that is due to an uplink transmission from the second user device is less than or equal to the threshold, an additional interference indication message, by the first base station to the second base station.

11. An apparatus comprising means for performing a method of any of claims 1-

10.

12. An apparatus comprising at least one processor and at least one memory including computer instructions that, when executed by the at least one processor, cause the apparatus to perform a method of any of claims 1-10.

13. An apparatus comprising a computer program product including a non- transitory computer-readable storage medium and storing executable code that, when executed by at least one data processing apparatus, is configured to cause the at least one data processing apparatus to perform a method of any of claims 1-10.

14. A method of reducing interference, comprising:

receiving, by a second base station associated with a second cell from a first base station associated with a first cell, an interference indication message indicating one or more resource blocks and a specific quantity of estimated interference increase at the second base station due to an uplink transmission via the one or more resource blocks from a user device that is connected to the first base station; and

sending, by the second base station to the first base station in response to the interference indication message, an interference reduction request message that requests the first base station to reduce an amount of interference increase at the second base station due to an uplink transmission from the user device.

15. The method of any of claim 14 wherein the interference reduction request message indicates one or more resource blocks and a requested reduced interference increase for one or more resource blocks that is less than the specific quantity of estimated interference increase for the one or more resource blocks.

16. The method of any of claims 14-15 wherein the estimated amount of interference increase at the second base station due to an uplink transmission from the user device comprises:

17. The method of any of claims 14-16 wherein the interference indication message comprises:

18. The method of any of claims 14-17 wherein the sending comprises: determining, by the second base station, service requirements for one or more users connected to the second base station;

determining, by the second base station, that the specific quantity of estimated interference increase at the second base station will negatively impact the ability of the second base station to meet the service requirements for one or more user devices connected to the second base station;

determining, by the second base station, a reduced amount of interference increase at the second base station that is less than the specific quantity of estimated interference increase and will provide less negative impact to the ability of the second base station to meet the service requirements for one or more user devices connected to the second base station; and

sending, by the second base station to the first base station in response to the interference indication message, an interference reduction request message indicating the reduced amount of interference increase that is requested by the second base station.

19. The method of claim 18 wherein the determining, by the second base station, a reduced amount of interference increase at the second base station considers both a quality of service or service requirements of the uplink transmission via the one or more resource blocks from the user device that is connected to the first base station and the service requirements for one or more users connected to the second base station.

20. The method of any of claims 14-19 wherein:

the receiving comprises:

receiving, by the second base station associated with a second cell from a first base station associated with a first cell, a first interference indication message indicating a first set of one or more resource blocks and a first specific quantity of estimated interference increase at the second base station due to an uplink transmission via the first set of one or more resource blocks from a user device that is connected to the first base station; and receiving, by the second base station from a third base station associated with a third cell, a second interference indication message indicating a second set of one or more resource blocks and a second specific quantity of estimated interference increase at the second base station due to an uplink transmission via the second set of one or more resource blocks from a user device that is connected to the third base station;

determining, by the second base station based on the first estimated interference increase and the second estimated interference increase, a first reduced amount of interference increase at the second base station that is less than the first specific quantity of estimated interference increase, and a second reduced amount of interference increase at the second base station that is less than the second specific quantity of estimated interference increase;

wherein the sending comprises:

sending, by the second base station to the first base station, a first interference reduction request message indicating the first reduced amount of interference increase that is requested by the second base station; and

sending, by the second base station to the third base station, a second interference reduction request message indicating the second reduced amount of

interference increase that is requested by the second base station.

21. An apparatus comprising means for performing a method of any of claims 14-

20.

22. An apparatus comprising at least one processor and at least one memory including computer instructions that, when executed by the at least one processor, cause the apparatus to perform a method of any of claims 14-20.

23. An apparatus comprising a computer program product including a non- transitory computer-readable storage medium and storing executable code that, when executed by at least one data processing apparatus, is configured to cause the at least one data processing apparatus to perform a method of any of claims 14-20.