WO2016099449A1

WO2016099449A1 - Flexible upstream and downstream loading

Info

Publication number: WO2016099449A1
Application number: PCT/US2014/070416
Authority: WO
Inventors: Edward Warner
Original assignee: Entropic Communications, Inc.
Priority date: 2014-12-15
Filing date: 2014-12-15
Publication date: 2016-06-23

Abstract

Systems and methods are provided for achieving the benefits of a frequency division duplex (FDD) system as well as that of a time division duplex (TDD) system. For example, switching between two diplexers associated with providing two fixed upstream (US) to downstream (DS) bandwidth ratios can achieve the effects of a variable diplexer by varying the amount of time spent transmitting and receiving data in accordance with the two fixed US to DS bandwidth ratios. As another example, a single fixed bandwidth diplexer can be used to achieve the effects of a variable diplexer by using the respective frequency segments assigned to US and DS traffic for both US and DS traffic.

Description

FLEXIBLE UPSTREAM AND DOWNSTREAM LOADING

Technical Field

[0001] The present disclosure relates generally to communication networks. In particular, some embodiments provide systems and methods for providing flexible upstream and downstream loading by dynamically switching two fixed diplexers or by dynamically changing the direction of upstream and downstream bands.

Background

[0002] An increasing use of communications networks is for content delivery to customer premises by service providers. For example, service providers may operate hybrid Passive Optical Network (PON) and coaxial/coax networks. The c.LINK Access networks derived from the Multimedia over Coax Alliance (MoCA) technology are one type of network used for such content delivery system. For example, a network controller may be in communication with a plurality of network nodes, where the network controller may be an access network controller (NC) (sometimes referred to as a Network Coordinator) managed by an Operator/Service Provider (OSP) or Multiple System Operator (MSO), such as a cable company. Network nodes may comprise various Customer Premise Equipment (CPEs), such as televisions, computers, high-speed data modems, set-top boxes, or other network connected content delivery systems.

[0003] In an access network, downstream (DS) traffic is transmitted from an NC to one, some, or all of the CPEs. Upstream (US) traffic is transmitted from CPEs to the NC. Upstream traffic is generally transmitted one CPE at a time (sometimes referred to as upstream bursts). When an NC has information (sometimes referred to as "packets," or "datagrams") to send to CPEs, it can simply schedule and transmit such downstream traffic. Accordingly, little or no preparation and interaction is required between the NC and (destination) network nodes (or CPEs). However, upstream bursts require more preparation and interaction between network nodes and the NC in order for the NC to schedule traffic properly. Packets that originate at the CPE are destined for the NC (e.g., for processing by the NC, for relay onto the Internet, etc.) When a CPE has data to send, the CPE must inform the NC and wait for an upstream transfer to be scheduled.

[0004] To accommodate multiple devices on a given communication channel, a diplexer can be used. For example, one type of conventional diplexer may include two or more bandpass filters to allow multiple signals in different frequency bands to share the same communication link and to filter out the unwanted signals before providing the signal to a given device. Such diplexers can be utilized in both frequency division duplexing (FDD) and time division duplexing (TDD) systems to allow selective access to the physical layer by different signals in different or shared frequency bands, allowing multiple devices to share the same coaxial cable network.

Summary

[0005] In accordance with one embodiment, a method for flexible US and DS loading comprises determining a preferred US to DS bandwidth ratio depending on traffic conditions. The method further comprises dynamically switching between a first diplexer providing a first US to DS bandwidth ratio and a second diplexer providing a second US to DS bandwidth ratio such that an overall US to DS bandwidth ratio achieved by the dynamic switching matches the preferred US to DS bandwidth ratio.

[0006] In accordance with another embodiment, a device comprises: a first diplexer providing a first upstream (US) to downstream (DS) bandwidth ratio; a second diplexer providing a second US to DS bandwidth ratio; a receive section for receiving DS traffic; and a transmit section for transmitting US traffic. The device switches between the first diplexer and the second diplexer such that an aggregate US to DS bandwidth ratio that is a function of a first amount of time spent utilizing the first diplexer providing the first US to DS bandwidth ratio and a second amount of time spent utilizing the second diplexer providing the second US to DS bandwidth ratio.

[0007] In accordance with still another embodiment, a method of US and DS loading in a network, comprises determining a preferred US to DS bandwidth ratio depending on traffic conditions. The method further comprises switching between utilizing a first filter associated with a first frequency segment and a second filter associated with a second frequency segment for US and DS traffic such that utilization of the first and second frequency segments to handle the US and DS traffic results in the preferred US to DS bandwidth ratio.

[0008] In accordance with yet another embodiment, a device, comprises a receive section for receiving DS traffic, a transmit section for transmitting US traffic, a diplexer, and a switching apparatus. The switching apparatus switches between utilizing a first filter of the diplexer associated with a first frequency segment and a second filter of the diplexer associated with a second frequency segment for US and DS traffic such that utilization of the first and second frequency segments to handle the US and DS traffic results in the preferred US to DS bandwidth ratio.

[0009] Other features and aspects of the disclosed technology will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the features in accordance with embodiments of the disclosed technology. The summary is not intended to limit the scope of any inventions described herein, which are defined solely by the claims attached hereto.

Brief Description of the Drawings

[0010] Various embodiments are described in detail with reference to the following figures. The drawings are provided for purposes of illustration only and merely depict typical or example embodiments. These drawings are provided to facilitate the reader's understanding and shall not be considered limiting of the breadth, scope, or applicability of the invention. It should be noted that for clarity and ease of illustration these drawings are not necessarily made to scale.

[0011] FIG. 1 illustrates a block diagram of an example diplexer and transmit and receive sections that may be utilized in a FDD system.

[0012] FIG. 2 illustrates a block diagram of an example diplexer and transmit and receive sections that may be utilized in an TDD system.

[0013] FIG. 3 illustrates an example access network using a point-to- multipoint topology within which various embodiments of the technology disclosed herein may be implemented. [0014] FIG. 4 illustrates another example access network using a mesh topology within which various embodiments of the technology disclosed herein may be implemented.

[0015] FIG. 5 illustrates a block diagram of an example network node.

[0016] FIG. 6 illustrates a block diagram of an example dynamically switched dual diplexer node in accordance with one embodiment of the technology disclosed herein.

[0017] FIGS. 7 A and 7B illustrate example frequency plans resulting from the use of the dynamically switched dual diplexer node of FIG. 6.

[0018] FIG. 8 illustrates an operational flow chart of example processes performed for dynamic upstream and downstream loading in accordance with one embodiment of the technology disclosed herein.

[0019] FIG. 9 illustrates a block diagram of an example of a direction switched single diplexer node in accordance with another embodiment of the technology disclosed herein.

[0020] FIG. 10 illustrates an operational flow chart of example processes performed for dynamic upstream and downstream loading in accordance with another embodiment of the technology disclosed herein.

[0021] FIG. 11 illustrates an example computing module that may be used in implementing various features of embodiments.

[0022] The figures are not intended to be exhaustive or to limit the invention to the precise form disclosed. It should be understood that embodiments can be practiced with modification and alteration, and that the invention be limited only by the claims and the equivalents thereof. Description

[0023] As described above, in an access network, DS traffic is transmitted from an NC to one, some, or all of the CPEs, while US traffic is transmitted from CPEs to the NC. For example, in DOCSIS, a standard that permits high-speed data transfer to an existing cable TV system (e.g., over a hybrid fiber- coaxial infrastructure), a device at a cable operator's headend, e.g., a Cable Modem Termination System (CMTS), sends data to end-user cable modems (in the DS frequency spectrum or band between, e.g., 54MHz up to 1000MHz. Cable modems that desire to send data back to the CMTS use an US frequency band between 5MHz to 42MHz.

[0024] It may be desirable to increase the system capacity of an access network in many applications. For example, there is a strong demand for low cost per CPE networks and high network capacity in terms of throughput and number of users supported, especially in the China access market. Considering that a single channel may be able to support an aggregate throughput of 100 MHz, in an FDD access network, where US and DS traffic occupy different frequencies, increasing US and DS capacity would entail upgrading amplifiers and other network devices with fixed filters. For example, in DOCSIS, increasing DS capacity might entail the implementation of filters that go to higher frequencies. However, increasing US capacity would be problematic due to the US being limited by its low end, e.g., 0MHz, and up to the desired frequency stop band. In a TDD access network, bandwidth can be time-sliced, thereby allowing for, e.g., the constant transmission of DS packets for some period of time or DS cycle, and the constant transmission of US packets for some other period of time or US cycle, achieving 100MHz in each direction at any one time. [0025] An FDD access network has certain advantages in that bandwidth and hardware resources are utilized more efficiently than in a TDD network (i.e., transmission and receipt of packets can occur in both directions at the same time). Moreover, an FDD access network need only operate at half the rate of a TDD network while achieving the same aggregate throughput. However, designing and implementing diplexers that can accommodate or are variable over the entire bandwidth associated with both the US and DS frequency spectrum would be very expensive, difficult to manufacture, and/or not practical in low-cost environments.

[0026] FIG. 1 illustrates a high-level block diagram of a node 1 that may be utilized in an FDD access network. Node 1 may include a coaxial jack or plug 2 providing connectivity to a cable plant. A diplexer 3 that includes, in this example, two bandpass filters 4 and 5, may be utilized to separate/combine transmit (Tx) and receive (Rx) signals from Rx and Tx portions 8 and 9 (US low frequencies and DS high frequencies, respectively) of node 1 on, e.g., a coaxial cable. It should be noted that although various embodiments are disclosed herein as utilizing diplexers employing bandpass filters, other embodiments contemplate the use of diplexers embodied with high pass and low pass filters. Moreover, bandpass filters may be variations of high pass and low pass filters. Node 1 may also include a low noise amplifier (LNA) 6 for amplifying the received signal and a high power amplifier (HPA) 7 for increasing the power of the transmitted signal. It should be noted that FIG. 1 and its above-described components are described at a high level, and additional components known to those skilled in the art may be included as well. Again, in an FDD access network, node 1 can transmit and receive simultaneously.

[0027] Bandpass filters are used to allow signals of certain frequencies to pass while rejecting, or filtering out, signals in other frequency bands. The bandpass filters pass signals within a certain band of frequencies of a desired bandwidth. This is known as the pass band of the bandpass filter. The bandwidth is typically defined as the frequency range between two cut-off points. The frequency cutoff points are typically 3dB below the maximum center or resonant peak, although other parameters can be used to specify the operable passband of the bandpass filter. Frequency ranges outside the passband are often referred to as the stop band of the bandpass filter. With some filters there may be a transition region between the passband and the stop band. In most applications, the bandpass filter is used to allow frequencies within the passband to be passed through the filter while rejecting, or filtering out, unwanted frequencies outside the passband.

[0028] In addition to specifying a passband, bandpass filters may specify a level of rejection (typically in dB) for the stop band. Also, one or more frequency ranges of high rejection may be specified to filter out signals in a frequency range of particular interest. The level of rejection specified as being a high level of rejection for the filter depends on the system application and the signals anticipated on the communication channel. For example, it may be known in a given application that signals in a certain frequency range may be present and that such signals, if allowed to pass, would cause interference on the channel with desired signals in the passband. As such, the system designer would specify a sufficient level of rejection in that band (or across a wider band) to reduce the interference to a desired level to allow system performance to meet specifications. As one of ordinary skill in the art will understand, other levels of isolation can be specified for a frequency range of high rejection. Note that in some applications, the entire stop band may be specified as requiring a high level of rejection. [0029] On the other hand, a TDD access network, unlike an FDD network where the US and DS bandwidth is generally fixed via a diplexer, can be used in either the US or DS direction at any given time depending on user loading (as previously discussed). This allows a TDD access network greater flexibility to support the respective demands of US and DS traffic. However, while a TDD access network may have full flexibility, it can only transmit in one direction at any one time, wasting hardware resources, i.e., only the Rx or the Tx side can be used at any one time.

[0030] FIG. 2 illustrates a high-level block diagram of a node 10 that may be utilized in a TDD access network. Node 10 may include a coaxial jack or plug 11 providing connectivity to a cable plant. Diplexer 12 can include a bandpass filter 13 and can be switched to handle US or DS traffic accordingly when handling Tx and Rx signals from Rx and Rx portions 16 and 17 (US low frequencies and DS high frequencies). Here, a single bandpass filter 13 is utilized because in a TDD access network, US and DS traffic are shared on the same frequency (just time sliced to handle both directions of traffic in an alternating fashion). Node 10 may also include an LNA 14 for amplifying the received signal and an HPA 15 for increasing the power of the transmitted signal. It should be noted that FIG. 2 and its above- described components are described at a high level, and additional components known to those skilled in the art may be included as well.

[0031] Various embodiments are directed to systems and methods for

US and DS loading that can achieve the advantages of both FDD and TDD systems, while negating their respective disadvantages. That is, the flexibility to handle different US and DS loads, i.e., vary the amount of channel bandwidth (as in a TDD access network) can be achieved while utilizing only a single or dual fixed diplexer system (as in an FDD access network) that can operate simultaneously. In particular, and in accordance with one embodiment, a switched diplexer approach can be utilized where an NC, acting as a network master, can dynamically select and switch between two diplexers based on US and DS traffic demands. In accordance with another embodiment, a single fixed diplexer approach may be utilized, where the directions of the US and DS portions of the frequency spectrum can be switched depending on traffic conditions.

[0032] FIG. 3 illustrates an example access network 18 in which various embodiments may be implemented. In this access network, an access controller 20 is in communication with a plurality of network nodes 19, e.g., Node 1, Node 2,..., and Node N. For example, access controller 20 may be an NC (sometimes referred to as a Network Coordinator) managed by an OSP or MSO, such as a cable company. Network nodes 19 may comprise various CPEs, such as televisions, computers, high-speed data modems, set-top boxes, or other network connected content delivery systems. Such an access network 18 may be arranged in a point-to- multipoint topology. In a point- to-multipoint topology, network nodes 19 communicate with access controller 20 and access controller 20 communicates with each of network nodes 19 (Node 1, Node 2, Node N). However, network nodes 19 themselves may not necessarily communicate with each other. In access networks like c.LINK, hundreds of CPEs can be in communication with a single NC.

[0033] FIG. 4 illustrates another example network 22 in which various embodiments may be implemented, and where NC 26 is in communication with a plurality of network nodes 24, e.g., Node 1, Node 2,..., and Node N. However, network 22 is arranged in using a mesh topology, where network nodes 24, unlike network nodes 19, are allowed to communicate with each other. MoCA in-home networks (HNs) similar to the MoCA standard use mesh topologies with multipoint- to-multipoint topologies, where multiple nodes can communicate with a plurality of other nodes.

[0034] In many communications networks, physical layer (PHY) packets are transmitted using orthogonal frequency division multiplexing (OFDM) for modulating data. OFDM is a digital multi-carrier modulation method in which a frequency band corresponding to a carrier comprises a number of closely spaced orthogonal subcarriers that are used to transport data. Data is divided into separate streams to be carried on the subcarriers. Each link between a pair of network nodes has a modulation profile in each direction that specifies the density of the modulation used on the subcarriers transmitted in that direction.

[0035] Each subcarrier is modulated using quadrature amplitude modulation (QAM). In QAM, the phases of two carrier waves at the same frequency are modulated. The two subcarriers are termed the quadrature (Q) component and the in phase (I) component. For example, in accordance with one modulation profile, a first subcarrier employs 16-QAM. In accordance with 16-QAM, 16 constellation points represent one of the 16 possible values that can be represented by a four bit binary information word. A second subcarrier employs a denser modulation, such as 64-QAM (having 64 possible constellation points, each representing one of the 64 possible values of a 6 bit information word). Each of the other subcarriers has a particular modulation density which may be greater than, less than, or the same as the first and second subcarriers.

[0036] In MoCA networks, binary phase shift keying (BPSK) and quadrature phase shift keying (QPSK) are considered less dense QAM modulation schemes and are also used. The denser a modulation profile, the less robust the communication. A more dense profile means more constellation points. In turn, more constellation points means more bits transmitting in the same amount of time. A signal that is transmitted using a more dense modulation scheme will be more susceptible to noise and other factors in the channel that can cause the packet error rate to be higher.

[0037] FIG. 5 illustrates a simplified block diagram of one example of a network node 30. As shown in FIG. 5, network node 30 may include a physical interface 32 including a transmitter 34 and a receiver 36, which are in data communication with a processor 38 through a data bus 42. The transmitter 34 may include a modulator 44 for modulating data onto a plurality of OFDM subcarriers according to a quadrature amplitude modulation (QAM) scheme such as, for example, 8-QAM, 16-QAM, 32-QAM, 64-QAM, 128-QAM, or 256-QAM, to name a few, and a digital-to-analog converter (DAC) 46 for transmitting modulated signals to other network nodes through a communication medium 56. It should be noted that various embodiments presented herein may be described as operating with one or more orders of modulation. However, these descriptions are merely examples, and not intended to be limiting in any way, were other orders of modulation may be possible.

[0038] Receiver 36 may include an analog-to-digital converter (ADC)

48, which can be a broadband ADC, for converting a modulated analog signal received from another network node into a digital signal. Receiver 36 may also include an automatic gain control (AGC) circuit 50 for adjusting the gain of the receiver 36 to properly receive the incoming signal, a demodulator 52 for demodulating the received signal, and a decoder 54 for decoding parity check codewords such as, for example, low-density parity check (LDPC) codewords, BCH codewords, or codewords for another coding scheme. One skilled in the art will understand that the network node 30 may include additional circuitry and functional elements not described herein.

[0039] Processor 38 may be any central processing unit (CPU), microprocessor, micro-controller, or computational device or circuit for executing instructions. As shown in FIG. 5, the processor 38 is in signal communication with a memory unit 40 through data bus 42.

[0040] As described above, data packets are transmitted over a coaxial communication channel using OFDM, and the communication through the network is managed by an NC node. The NC may be any network node and may switch from node to node as nodes are added and removed from the network. The NC periodically broadcasts beacons and Media Access Plan (MAP) packets to the nodes connected to the network. The beacons are transmitted at regular intervals (e.g., every 10 ms) and identify the channel time clock (CTC), the MoCA network version, the time of the next admission control frame (ACF), and when a NC handoff will occur (e.g., when the NC changes from one network node to another network node). MAP packets are transmitted more frequently by the NC than are beacons and provide scheduling information that identify when each network node will be transmitting data through the network. The NC may receive reservation requests (RRs) from each of the plurality of nodes between MAP packet transmissions in which the network nodes report their transmission capabilities and request to transmit data to other network nodes.

[0041] FIG. 6 illustrates a block diagram of a node 60 having two diplexers between which switching can occur to vary the ratio of US and DS bandwidth in accordance with one embodiment of the technology disclosed herein. Referring back to FIG. 1, in a conventional FDD access network, a node, e.g., node 1 may utilize a single fixed diplexer 3 to process US and DS traffic simultaneously, the fixed aspect referring to bandpass filters 4 and 5 each having a fixed bandwidth. Referring back to FIG. 2, in a conventional TDD access network, node 10 switches diplexer 12 between US and DS in accordance with traffic demands. In contrast to both node implements in the conventional FDD and TDD access networks, and with the use of fast switching tuners (not shown), node 60 can switch between two fixed bandwidth diplexers 64 and 70.

[0042] Diplexer 64 may include two bandpass filters 66 and 68, each having a pass band resulting in a particular US/DS ratio, e.g., 20% US and 80% DS, that can be provided. Diplexer 70 may also include two bandpass filters 72 and 74, each having a pass band resulting in another US/DS ratio, e.g., 80% US and 20% DS, that can be provided. In accordance with one embodiment, node 60 switches between diplexers 64 and 66. The length of time spent providing one or the other ratio (mode of operation) can be varied such that a desired overall or aggregate ratio can be achieved to accommodate the US or DS traffic load. For example, switching between the 20% US /80% DS ratio mode and the 80% US/20% DS ratio mode and spending equal amounts of time in each mode would effectively result in providing overall or aggregate US/DS ratio that is 50% US and 50% DS. If more DS bandwidth or capacity was desired, node 60 could switch to utilizing diplexer 64 for a longer period of time relative to the time spent utilizing diplexer 66 to achieve, e.g., a 60% DS and 40% US ratio. If more US capacity was desired, node 60 could switch to diplexer 70 and spend more time providing that higher US capacity ratio (80% US/20% DS) to achieve, i.e., a 70% US and 30% DS ratio.

[0043] Like nodes 1 and 10 of FIGS. 1 and 2, node 60 may further include a coaxial jack or plug 62 providing connectivity to a cable plant. Further still, node 60 may include an LNA 76 for amplifying the received signal from Rx portion 80, and an HPA 78 for increasing the power of the transmitted signal from Tx portion 82.

[0044] Thus, variable or flexible US and DS usage can be provided without the use of expensive, hard-to-manufacture, impractical "variable" diplexers, while also being able to operate at full efficiency, i.e., allowing for the simultaneous transmission of both US and DS traffic. It should be noted that this embodiment can be applied to multi-channel systems as well as single channel systems

[0045] FIGS. 7 A and 7B illustrate example frequency domain representations of the above-described switching between two fixed diplexers that can be implemented in node 60 of FIG. 6. FIG. 7A illustrates that in a first mode, a network or system (which can include one or more channels) can switch to utilizing diplexer 64 which can provide a smaller US to higher DS ratio, such as 20% US and 80% DS capacity. In other words, US data packets will be transmitted 20% of the time and DS data packets will be transmitted 80% of the time. FIG. 7B illustrates that in a second mode, node 60 can switch to utilizing diplexer 70 which can provide a higher US to smaller DS ratio, such as 80% US and 20% DS capacity. In other words, the network will transmit US data packets 80% of the time and will transmit DS data packets 20% of the time. It should be noted that individual nodes may be operating at other US/DS ratios or at least desire to operate at other US/DS ratios, such individual nodes being constrained by the "aggregate" US/DS ratios.

[0046] In operation, an access network (which can be a c.LINK network, for example), using a TDD scheme allows nodes to transmit on the same frequency during different time slots which may be coordinated by an NC. Per the TDD scheme, access to a medium may be controlled by the NC, and the NC can divide transmission time into units referred to as MAP cycles, each MAP cycle further being divided to accommodate US and DS traffic. These MAP cycles are repeated between beacon transmissions, with a beacon cycle (i.e., the time interval between two consecutive beacons) being typically fixed (e.g. c.LINK has a beacon interval of 10ms). It should be noted that the number of MAP cycles, the arrangement/structure of MAP cycles between beacon transmissions, the allocation/division of US and DS traffic within each MAP cycle, the length of MAP cycles, can all vary in accordance with design/performance characteristics that may be desired in an access network as will be described below.

[0047] As actual traffic on an access network typically changes over time, the ratio of US cycle to DS cycle within a MAP cycle (described above) can be adjusted. As would be understood, the access network may experience disparities regarding the amount of US and DS traffic at any given time. For example, at one point in time, a majority of CPEs may be receiving streaming media, and hence, DS traffic may be much greater than US traffic. Accordingly, an OSP/MSO may wish to adjust how much of a channel is allotted for US and DS traffic. The US to DS ratio can be adjusted either statically, by a network operator through a Network Management System, or preferably, dynamically, by the access network itself, via monitoring of conditions and condition changes of actual traffic.

[0048] To implement dynamic US to DS ratio adjustment, the host processor can track DS traffic for bandwidth management purposes. For US traffic needs, each NC can be configured to report RRs from all CPES to the host processor. The host processor can therefore be aware of both DS and US traffic for each channel. For each CPE and for each channel, the host may build a moving average of N milliseconds for DS and US bandwidth requirements. From this, the host processor can determine an optimal ratio between the US cycle and the DS cycle of the MAP cycle, taking into account bitloading profiles in each direction. Furthermore, the host processor may pass the US-to-DS ratio value to all the NCs, either through in-band messaging or out-of-band messaging, where in the in-band or out-of-band message, the host processor may also specify a channel-time-clock (CTC) value after which the US-to-DS ratio is to take effect. It should be noted that the US/DS ratio can be adjusted at the level of even a single MAP cycle, where a first portion of a MAP cycle may operate at a first US/DS ratio and a second portion of the MAP cycle may operate at a second US/DS ratio.

[0049] FIG. 8 is an operational flow chart illustrating processes that can be performed to provide flexible US and DS loading in accordance with one embodiment of the technology disclosed herein. At operation 84, a preferred US to DS bandwidth ratio is determined based on the determined traffic conditions. As previously discussed, the access network itself or a network management system can monitor network conditions and how traffic thereon my change. At operation 86, dynamic switching can be performed between a first diplexer providing a first US to DS bandwidth ratio and a second diplexer providing a second US to DS bandwidth ratio such that an overall US to DS bandwidth ratio achieved by the dynamic switching matches the preferred US to DS bandwidth ratio. That is, the first US to DS bandwidth ratio of the first diplexer may be skewed to a larger DS bandwidth, whereas the second US to DS bandwidth ratio of the second diplexer may be skewed to a smaller DS bandwidth. Accordingly, and depending on the time spent (via the dynamic switching) in either mode, the preferred overall US to US bandwidth ratio can be achieved despite the first and second diplexers having fixed filters/US to DS bandwidth ratios. [0050] FIG. 9 illustrates a block diagram of a node 90 having a diplexer 94. Again, referring back to FIG. 1, in a conventional FDD access network, node 1 may utilize a single fixed diplexer 3 to process US and DS traffic simultaneously, and referring back to FIG. 2, in a conventional TDD access network, node 10 switches diplexer 12 between US and DS in accordance with traffic demands. In contrast to the conventional node implementations in FDD and TDD access networks illustrated in FIGS. 1 and 2, node 90 can switch the respective directions of the US and DS bands. Node 90 may include a diplexer 94, which in turn, can include two bandpass filters 96 and 98. That is, for a first duration, bandpass filter 96 may pass signals corresponding to US traffic received by the Rx portion 104 of node 90 and bandpass filter 98 may pass signals corresponding to DS traffic transmitted by the Tx portion 106 of node 90. For a second duration, bandpass filter 96 may be switched such that it operatively connects to Tx portion 106 of node 90, thereby now passing signals corresponding to DS traffic, while bandpass filter 98 may be switched such that is operatively connects to Rx portion 104 of node 90, thereby now passing signals corresponding to US traffic.

[0051] Like conventional node 1 in a conventional FDD access network, US and DS traffic can be received and transmitted simultaneously, and also like node 10 in a conventional TDD access network, US and DS traffic can be received and transmitted in accordance with the "full" bandwidth according to the bandpass filter bandwidth ratio. That is, if bandpass filters 96 and 98 support a US to DS bandwidth ratio of 20% to 80%, respectively, any bandwidth ratio between the US to DS bandwidth ratio of 20% to 80% can be supported depending on how long either of bandpass filters 96 or 98 are switched on and depending on whether they are passing US or DS data packets. Also nodes 1 and 10 of FIGS. 1 and 2, node 90 may further include a coaxial jack or plug 92 providing connectivity to a cable plant. Further still, node 90 may include an LNA 100 for amplifying the received signal from Rx portion 104 and an HPA 102 for increasing the power of the transmitted signal from Tx portion 74.

[0052] Therefore and again, variable or flexible US and DS usage can be provided without the use of expensive, hard-to-manufacture, impractical "variable" or filter-bank diplexers, while also being able to operate at full efficiency, i.e., allowing for the simultaneous transmission of both US and DS traffic. Like the aforementioned embodiment, it should be noted that this embodiment can be applied to multi-channel systems as well as single channel. Moreover, and although various embodiments are herein discussed in the context of access networks, various embodiments can be implemented in a myriad of network types, whether LAN, WAN, point- to-multipoint, mesh, etc.

[0053] FIG. 10 is an operational flow chart illustrating processes that can be performed to provide flexible US and DS loading in accordance with another embodiment of the technology disclosed herein. At operation 108, a preferred US to DS bandwidth ratio is determined based on the determined traffic conditions. As previously discussed, the access network itself or a network management system can monitor network conditions and how traffic thereon my change. At operation 110, switching between utilization of a first filter associated with a first frequency segment and a second filter associated with a second frequency segment for US and DS traffic is performed such that utilization of the first and second frequency segments to handle the US and DS traffic results in the preferred US to DS bandwidth ratio. That is, during a first period, the first filter can be a bandpass filter passing signals associated with US traffic and the second filter can be a bandpass filter passing signals associated with DS traffic. During a second period, the first filter can be switched such that it passes signals associated with DS traffic. Likewise, during the second period, the second filter can be switched such that it passes signals associated with US traffic. Thus, the amount of bandwidth allocated to US and DS traffic can vary based on the portion of the frequency spectrum supported by a particular bandpass filter.

[0054] A Wide Area Network (WAN) link can be a point to point link or a point to multipoint link. In the context of a point to multipoint network, as described above, traffic flows between a master or headend node and the endpoints, while traffic does not flow directly between endpoints. In a Local Area Network (LAN) network, traffic can flow in either a point to multipoint fashion or in a full mesh mode, such that any LAN node can directly communicate with any other LAN node. Various embodiments can also be applied to a LAN-type or network operating in mesh mode. For example, if all LAN nodes are configured as described herein, both Tx and Rx sections can be used simultaneously, and overall network throughput can be enhanced to be the sum of the network's respective Rx and Tx capabilities.

[0055] Moreover, it should be noted that in any applicable network, elements such as network hardware can be optimized for operation in accordance with various embodiments. For example, while more rapid switching between diplexers or between frequency segments may be determined to be optimal in a theoretical context, in actual operation, it may be preferable to switch less often to, e.g., allow for certain latency when switching between frequencies, etc.

[0056] Figure 11 lustrates an example computing module that may be used to implement various features of the system and methods disclosed herein.

[0057] As used herein, the term module might describe a given unit of functionality that can be performed in accordance with one or more embodiments of the present application. As used herein, a module might be implemented utilizing any form of hardware, software, or a combination thereof. For example, one or more processors, controllers, ASICs, PLAs, PALs, CPLDs, FPGAs, logical components, software routines or other mechanisms might be implemented to make up a module. In implementation, the various modules described herein might be implemented as discrete modules or the functions and features described can be shared in part or in total among one or more modules. In other words, as would be apparent to one of ordinary skill in the art after reading this description, the various features and functionality described herein may be implemented in any given application and can be implemented in one or more separate or shared modules in various combinations and permutations. Even though various features or elements of functionality may be individually described or claimed as separate modules, one of ordinary skill in the art will understand that these features and functionality can be shared among one or more common software and hardware elements, and such description shall not require or imply that separate hardware or software components are used to implement such features or functionality.

[0058] Where components or modules of the application are implemented in whole or in part using software, in one embodiment, these software elements can be implemented to operate with a computing or processing module capable of carrying out the functionality described with respect thereto. One such example computing module is shown in Figure 11. Various embodiments are described in terms of this example-computing module 120. After reading this description, it will become apparent to a person skilled in the relevant art how to implement the application using other computing modules or architectures. [0059] Referring now to Figure 11, computing module 120 may represent, for example, computing or processing capabilities found within desktop, laptop, notebook, and tablet computers; hand-held computing devices (tablets, PDA's, smart phones, cell phones, palmtops, etc.); mainframes, supercomputers, workstations or servers; or any other type of special-purpose or general-purpose computing devices as may be desirable or appropriate for a given application or environment. Computing module 120 might also represent computing capabilities embedded within or otherwise available to a given device. For example, a computing module might be found in other electronic devices such as, for example, digital cameras, navigation systems, cellular telephones, portable computing devices, modems, routers, WAPs, terminals and other electronic devices that might include some form of processing capability.

[0060] Computing module 120 might include, for example, one or more processors, controllers, control modules, or other processing devices, such as a processor 124. Processor 124 might be implemented using a general-purpose or special-purpose processing engine such as, for example, a microprocessor, controller, or other control logic. In the illustrated example, processor 124 is connected to a bus 122, although any communication medium can be used to facilitate interaction with other components of computing module 120 or to communicate externally.

[0061] Computing module 120 might also include one or more memory modules, simply referred to herein as main memory 126. For example, preferably random access memory (RAM) or other dynamic memory might be used for storing information and instructions to be executed by processor 124. Main memory 126 might also be used for storing temporary variables or other intermediate information during execution of instructions to be executed by processor 124. Computing module 120 might likewise include a read only memory ("ROM") or other static storage device coupled to bus 802 for storing static information and instructions for processor 124.

[0062] The computing module 120 might also include one or more various forms of information storage devices 128, which might include, for example, a media drive 130 and a storage unit interface 134. The media drive 130 might include a drive or other mechanism to support fixed or removable storage media 132. For example, a hard disk drive, a floppy disk drive, a magnetic tape drive, an optical disk drive, a CD or DVD drive (R or RW), or other removable or fixed media drive might be provided. Accordingly, storage media 132 might include, for example, a hard disk, a floppy disk, magnetic tape, cartridge, optical disk, a CD or DVD, or other fixed or removable medium that is read by, written to or accessed by media drive 130. As these examples illustrate, the storage media 132 can include a computer usable storage medium having stored therein computer software or data.

[0063] In alternative embodiments, information storage devices 128 might include other similar instrumentalities for allowing computer programs or other instructions or data to be loaded into computing module 120. Such instrumentalities might include, for example, a fixed or removable storage unit 136 and an interface 134. Examples of such storage units 136 and interfaces 134 can include a program cartridge and cartridge interface, a removable memory (for example, a flash memory or other removable memory module) and memory slot, a PCMCIA slot and card, and other fixed or removable storage units 136 and interfaces 134 that allow software and data to be transferred from the storage unit 136 to computing module 120.

[0064] Computing module 120 might also include a communications interface 138. Communications interface 138 might be used to allow software and data to be transferred between computing module 120 and external devices. Examples of communications interface 138 might include a modem or softmodem, a network interface (such as an Ethernet, network interface card, WiMedia, IEEE 802.XX or other interface), a communications port (such as for example, a USB port, IR port, RS232 port Bluetooth® interface, or other port), or other communications interface. Software and data transferred via communications interface 138 might typically be carried on signals, which can be electronic, electromagnetic (which includes optical) or other signals capable of being exchanged by a given communications interface 138. These signals might be provided to communications interface 138 via a channel 140. This channel 140 might carry signals and might be implemented using a wired or wireless communication medium. Some examples of a channel might include a phone line, a cellular link, an RF link, an optical link, a network interface, a local or wide area network, and other wired or wireless communications channels.

[0065] In this document, the terms "computer program medium" and

"computer usable medium" are used to generally refer to transitory or non-transitory media such as, for example, memory 126, storage unit 136, media 132, and channel 140. These and other various forms of computer program media or computer usable media may be involved in carrying one or more sequences of one or more instructions to a processing device for execution. Such instructions embodied on the medium, are generally referred to as "computer program code" or a "computer program product" (which may be grouped in the form of computer programs or other groupings). When executed, such instructions might enable the computing module 120 to perform features or functions of the present application as discussed herein. [0066] Although described above in terms of various exemplary embodiments and implementations, it should be understood that the various features, aspects and functionality described in one or more of the individual embodiments are not limited in their applicability to the particular embodiment with which they are described, but instead can be applied, alone or in various combinations, to one or more of the other embodiments of the application, whether or not such embodiments are described and whether or not such features are presented as being a part of a described embodiment. Thus, the breadth and scope of the present application should not be limited by any of the above-described exemplary embodiments.

[0067] Terms and phrases used in this document, and variations thereof, unless otherwise expressly stated, should be construed as open ended as opposed to limiting. As examples of the foregoing: the term "including" should be read as meaning "including, without limitation" or the like; the term "example" is used to provide exemplary instances of the item in discussion, not an exhaustive or limiting list thereof; the terms "a" or "an" should be read as meaning "at least one," "one or more" or the like; and adjectives such as "conventional," "traditional," "normal," "standard," "known" and terms of similar meaning should not be construed as limiting the item described to a given time period or to an item available as of a given time, but instead should be read to encompass conventional, traditional, normal, or standard technologies that may be available or known now or at any time in the future. Likewise, where this document refers to technologies that would be apparent or known to one of ordinary skill in the art, such technologies encompass those apparent or known to the skilled artisan now or at any time in the future.

[0068] The presence of broadening words and phrases such as "one or more," "at least," "but not limited to" or other like phrases in some instances shall not be read to mean that the narrower case is intended or required in instances where such broadening phrases may be absent. The use of the term "module" does not imply that the components or functionality described or claimed as part of the module are all configured in a common package. Indeed, any or all of the various components of a module, whether control logic or other components, can be combined in a single package or separately maintained and can further be distributed in multiple groupings or packages or across multiple locations.

[0069] Additionally, the various embodiments set forth herein are described in terms of exemplary block diagrams, flow charts and other illustrations. As will become apparent to one of ordinary skill in the art after reading this document, the illustrated embodiments and their various alternatives can be implemented without confinement to the illustrated examples. For example, block diagrams and their accompanying description should not be construed as mandating a particular architecture or configuration.

Claims

1. A method of upstream (US) and downstream (DS) loading in a network, comprising:

determining a preferred US to DS bandwidth ratio depending on traffic conditions; and

dynamically switching between a first diplexer providing a first US to DS bandwidth ratio and a second diplexer providing a second US to DS bandwidth ratio such that an overall US to DS bandwidth ratio achieved by the dynamic switching matches the preferred US to DS bandwidth ratio.

2. The method of claim 1, wherein the access network comprises a frequency division duplex network.

3. The method of claim 1, wherein the access network comprises a time division duplex network.

4. The method of claim 1, wherein the first diplexer comprises a first bandpass filter and a second bandpass filter.

5. The method of claim 4, wherein the first bandpass filter passes US signals in accordance with a frequency segment of a frequency spectrum reserved for US traffic, and, wherein the second bandpass filter passes DS signals in accordance with a frequency segment of the frequency spectrum reserved for DS traffic.

6. The method of claim 5, wherein the respective frequency segments of the first and second bandpass filters is commensurate with the first US to DS bandwidth ratio.

7. The method of claim 1, wherein the second diplexer comprises a third bandpass filter and a fourth bandpass filter.

8. The method of claim 7, wherein the third bandpass filter passes DS signals in accordance with a frequency segment of a frequency spectrum reserved for US traffic, and wherein the second bandpass filter passes DS signals in accordance with a frequency segment of the frequency spectrum reserved for US traffic.

9. The method of claim 8, wherein the respective frequency segments of the third and fourth bandpass filters is commensurate with the second US to DS bandwidth ratio.

10. A device, comprising:

a first diplexer providing a first upstream (US) to downstream (DS) bandwidth ratio;

a second diplexer providing a second US to DS bandwidth ratio;

a receive section for receiving DS traffic; and

a transmit section for transmitting US traffic, wherein the device switches between the first diplexer and the second diplexer such that an aggregate US to DS bandwidth ratio that is a function of a first amount of time spent utilizing the first diplexer providing the first US to DS bandwidth ratio and a second amount of time spent utilizing the second diplexer providing the second US to DS bandwidth ratio.

11. The device of claim 10, wherein the first diplexer comprises a first bandpass filter and a second bandpass filter.

12. The device of claim 11, wherein the first bandpass filter passes US signals in accordance with a frequency segment of a frequency spectrum reserved for US traffic, and, wherein the second bandpass filter passes DS signals in accordance with a frequency segment of the frequency spectrum reserved for DS traffic.

13. The device of claim 12, wherein the respective frequency segments of the first and second bandpass filters is commensurate with the first US to DS bandwidth ratio.

14. The device of claim 10, wherein the second diplexer comprises a third bandpass filter and a fourth bandpass filter.

15. The device of claim 14, wherein the third bandpass filter passes DS signals in accordance with a frequency segment of a frequency spectrum reserved for US traffic, and wherein the second bandpass filter passes DS signals in accordance with a frequency segment of the frequency spectrum reserved for US traffic.

16. The device of claim 10 comprising a network node.

17. The device of claim 10, wherein the network node is a node of one of a point- to-multi-point network or a mesh network.

18. A method of upstream (US) and downstream (DS) loading in an access network, comprising:

switching between utilizing a first filter associated with a first frequency segment and a second filter associated with a second frequency segment for US and DS traffic such that utilization of the first and second frequency segments to handle the US and DS traffic results in the preferred US to DS bandwidth ratio.

19. The method of claim 18, wherein the first filter and the second filter comprise a diplexer for combining and separating the US and DS traffic along a coaxial cable.

20. The method of claim 19, wherein the first filter comprises a bandpass filter having a first pass band commensurate with the first frequency segment, and wherein the second filter comprises a bandpass filter having a second pass band commensurate with the second frequency segment.

21. A device, comprising:

a receive section for receiving DS traffic;

a transmit section for transmitting US traffic;

a diplexer; and

a switching apparatus for switching between utilizing a first filter of the diplexer associated with a first frequency segment and a second filter of the diplexer associated with a second frequency segment for US and DS traffic such that utilization of the first and second frequency segments to handle the US and DS traffic results in the preferred US to DS bandwidth ratio.

22. The device of claim 21, wherein the first filter comprises a bandpass filter having a first pass band commensurate with the first frequency segment, and wherein the second filter comprises a bandpass filter having a second pass band commensurate with the second frequency segment.

23. The device of claim 21 comprising a network node.

24. The device of claim 23, wherein the network node is a node of one of a point- to-multi-point network or a mesh network.