WO2004068779A1 - Uplink sinr estimation - Google Patents
Uplink sinr estimation Download PDFInfo
- Publication number
- WO2004068779A1 WO2004068779A1 PCT/CN2003/000101 CN0300101W WO2004068779A1 WO 2004068779 A1 WO2004068779 A1 WO 2004068779A1 CN 0300101 W CN0300101 W CN 0300101W WO 2004068779 A1 WO2004068779 A1 WO 2004068779A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- channelization code
- idle
- selecting
- channel
- uplink
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/20—Arrangements for detecting or preventing errors in the information received using signal quality detector
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/69—Spread spectrum techniques
- H04B1/707—Spread spectrum techniques using direct sequence modulation
- H04B1/7097—Interference-related aspects
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J13/00—Code division multiplex systems
- H04J13/0007—Code type
- H04J13/004—Orthogonal
- H04J13/0044—OVSF [orthogonal variable spreading factor]
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J13/00—Code division multiplex systems
- H04J13/16—Code allocation
- H04J13/18—Allocation of orthogonal codes
- H04J13/20—Allocation of orthogonal codes having an orthogonal variable spreading factor [OVSF]
Definitions
- the present invention relates to estimation of the Signal to Interference plus Noise Ratio (SINR) of Code Division Multiple Access (CDMA) channels.
- SINR Signal to Interference plus Noise Ratio
- the SINR is an important link performance indicator used in CDMA systems for various radio network algorithms, such as inner-loop power control.
- the SINR estimation is very critical, since it indirectly affects the power management at both base station and mobile station. It is required that the estimated SINR actually reflects the experienced radio link quality and, moreo- ver, that the estimation is as accurate as possible.
- the SINR estimate is formed by measuring the signal power "S”, and the interference plus noise power, "IN". Although it is quite straightforward to measure "S”, it is far from obvious how to measure "IN”.
- a previously known method of estimating the power of interference plus noise (IN) is to re-generate the pilot symbols (after de-spreading) and calculate their average deviation from the ideal signal points.
- SINR is measured every time slot, there are only a few (2-8) pilot symbols available, which means that the obtainable accuracy of the IN measurement is very limited. Since the same IN estimate is used for SINR estimation of any channel, it is appreciated that these estimates will also have limited accuracy.
- Another method described in [1, 2] is to reserve one downlink channelization code as an "interference plus noise measurement code" which is never used for information transfer.
- This method generates a downlink IN estimate by de-spreading the received signal with the reserved code.
- An object of the present invention is to improve the accuracy of the uplink SINR estimation, and especially of the interference plus noise estimation, without requiring an changes to existing standards.
- the present invention selects an idle (not used) channelization code, which preferably has the lowest possible spreading factor, and uses this code to estimate the power of interference plus noise.
- an idle code is selected, there is no need to change existing standards.
- Another advantage of using an idle code is that there will be no code shortage due to SINR measurements.
- the method makes it possible to search the code tree down to lowest possible spreading factor, thereby increasing the number of symbols in the IN measurement, which will result in a very high accuracy of the IN estimate.
- Fig. 1 is a conceptual block diagram of a prior art SINR estimation arrangement
- Fig. 2 is a diagram illustrating the structure of an OVSF code tree
- Fig. 3 is an OVSF code tree diagram illustrating idle codes when a single DPDCH is used
- Fig. 4 is an OVSF code tree diagram illustrating idle codes when 2 DPDCHs are used
- Fig. 5 is an OVSF code tree diagram illustrating idle codes when 3-4 DPDCHs are used;
- Fig. 6 is an OVSF code tree diagram illustrating idle codes when 5-6
- DPDCHs are used.
- Fig. 7 is a conceptual block diagram of an exemplary embodiment of a SINR estimation arrangement in accordance with the present invention.
- Fig. 8 is a conceptual block diagram of another exemplary embodiment of a SINR estimation arrangement in accordance with the present invention.
- Fig. 9 is a diagram illustrating the performance improvement that can be obtained by the present invention.
- Fig. 10 is a flowchart illustrating an exemplary embodiment of the method in accordance with the present invention.
- SINR bit ⁇ SINR ⁇ , for QPSK
- SINR for the demodulated raw bits
- SINRbit for the term “SINR”
- Fig. 1 illustrates a generic CDMA receiver with function blocks to estimate the SINR by utilizing the associated pilot.
- the associated pilot is a pre-known symbol/ bit that is transmitted at the same time (in the sense that both the multi-path channel and the interference plus noise power are almost non- varying) and from the same transmitter as the data.
- Both the dedicated pilot and common pilot in WCDMA and CDMA2000 are examples of such an associated pilot.
- Fig. 1 is a conceptual block diagram of a prior art SINR estimation arrangement.
- the received signal samples are forwarded to a receiver filter 10.
- Receiver filter 10 is either a multi-path channel matched filter or an equalizer.
- the filtered signal is de-scrambled by the complex conjugate SC* of the complex scrambling code.
- the de-scrambled signal is de-spread into two parallel signal streams rudata(n) and ru P aot(n) by multiplication with the respective channelization codes CCdat and CCpUot and integration in integrators 12 and 14, respectively.
- the pilot signal branch is used for the SINR estimation by first multiplying ru P ibt(n) with the complex conjugate of the corresponding known signal u P ii 0 t(n) for obtaining the product signal ruUpaot(n) on which the SINR measurement is based.
- SINR is then estimated in blocks 16, 18 and 20 using the following equations:
- SINR pilot Calculated in block 20
- This SINR estimation for the associated pilot follows the general SINR definition above, but removes the bias in the signal power estimation.
- the SINR of a data channel can be estimated by simply scaling the estimated SINR of the associated pilot:
- SFpiht the spreading factor for the associated pilot
- Pdata the transmission power for the data
- Ppiiot the transmission power for the associated pilot.
- the downlink employs QPSK modulation and the uplink employs BPSK modulation.
- the described method is typical for the uplink dedicated physical data channel utilizing the uplink dedicated pilot in WCDMA and CDMA2000 for SINR estimation. If this estimation method is used, then:
- SINRdata SINRpilot
- the estimated data SINR has the same accuracy as the estimated pilot SINR.
- the estimation accuracy is defined as: accuracy
- an estimated SINR should be generated every time slot (0.667 ms) and input to the inner-loop power control algorithm. If we assume that the multi-path channel and the interference plus noise power is almost non- varying during one time slot, then the demodulated raw bits are Gaussian distributed and the SINR is fixed during the whole time slot
- the estimation accura- cy relies on the number of associated pilots that are used in the estimation, the more pilots the higher estimation accuracy.
- One solution to improve the estimation accuracy is to measure the effective interference plus noise power on a different measurement object than the measurement of the signal power, so that more symbols can be utilized.
- an idle code is an OVSF code that is not occupied as a channelization code, or used to generate channelization code(s).
- Fig. 2 illustrates an OVSF code tree.
- the channelization codes are uniquely described as Cch.sF.k, where SF is the spreading factor of the code and k is the code number, 0 ⁇ k ⁇ SF-1.
- Each level in the code tree defines channelization codes of length SF, corresponding to a spreading factor of SF.
- each channelization code word corresponds to the chip transmitted first in time.
- An important feature of the OVSF code tree is that channelization codes from different branches are orthogonal to each other regardless of spreading factor SF. This feature is used by the present invention, as will be described below.
- the spreading factor (SF) of the idle code should preferably be as low as possible, so that as many symbols as possible can be used during the same time slot.
- the lowest SF for an idle code is 2 if all the used codes are from the same half of the OVSF tree. More specifically, if all channelization codes are derived from the OVSF code (1, 1), then OVSF code (1, -1) can be used as the idle code, or vice versa.
- the idle code channel may be viewed as a channel with zero transmission power, and by using the same analysis method as in [4] it can be shown that:
- the variance estimation of a desired channel may be performed on an idle channel instead.
- the estimated SINR for the desired code channel can be calculated as illustrated by the arrangement in Fig. 7, which illustrates the parts of a base station that are essential for explaining this exemplary embodiment of present invention.
- the de-scrambled signal is de-spread into two parallel signal streams ⁇ iDPccH(n) and ruidie(n) by multiplication with the respective channelization codes CCDPCCH and CCidie and integration in integrators 12 and 14, respectively.
- the idle channelization code has been selected by an idle code selection block 28 based on the OVSF code tree in Fig. 2 and occupied codes known to the base station. It may, for example, be implemented as a simple lookup table. SINR is then estimated in blocks 16, 30 and 32 using the following equations:
- Npihts is the number of pilot symbols used in the estimation
- Nidie is the number of idle symbols used in the estimation.
- the estimated SINR for the desired code channel can still be non-coherently calculated as illustrated by the arrangement in Fig. 8, which illustrates the parts of a base station that are essential for explaining this exemplary embodiment of present invention.
- the de-scrambled signal is de-spread into two parallel signal streams ruDP CH(n) and rUidie(n) by multiplication with the respective channelization codes CCDPDCH and CCidie and integration in integrators 12 and 14, respectively.
- the idle channelizati- on code has been selected by an idle code selection block 28 based on the OVSF code tree in Fig. 2 and occupied codes known to the base station. It may, for example, be implemented as a simple lookup table.
- NDPDCH is the number of signal symbols used in the estimation
- Nidie is the number of idle symbols used in the estimation.
- the functionality of the arrangement of the present invention is typically implemented as a microprocessor or a micro/ signal processor combination and corresponding software.
- the described prior art method only utilizes the 3 ⁇ 8 dedicated pilot symbols to estimate the SINR.
- the method in accordance with the present invention may maximally utilize 1280 (2560/2) "idle symbols" to measure the effective interference plus noise power during one time slot. This is a main benefit of using an idle code channel (with low spreading factor) to assist the SINR estimation.
- the new method can also utilize all of the 10 DPCCH symbols to measure the DPCCH power, and all symbols on the DPDCH channel to measure the DPDCH power.
- Fig. 9 is a diagram illustrating the performance improvement that can be obtained by the present invention.
- Step SI estimates the power of a desired channel using its channelization code.
- Step S2 searches for and selects a low SF idle channelization code from the OVSF tree using information regarding occupied channelization codes.
- Step S3 estimates the power of interference plus noise using the determined idle channelization code.
- Step S4 forms an estimate of SINR using the determined power estimates. If the channelization codes have different spreading factors, the estimates obtained in step S3 is rescaled accordingly.
- step S5 returns the procedure to step SI for estimating SINR of the next time slot.
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Quality & Reliability (AREA)
- Mobile Radio Communication Systems (AREA)
Abstract
Description
Claims
Priority Applications (7)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/542,535 US20060154633A1 (en) | 2003-01-29 | 2003-01-29 | Uplink sinr estimation |
CA002513318A CA2513318A1 (en) | 2003-01-29 | 2003-01-29 | Uplink sinr estimation |
EP03815510A EP1590911A4 (en) | 2003-01-29 | 2003-01-29 | Uplink sinr estimation |
JP2004567218A JP2006514452A (en) | 2003-01-29 | 2003-01-29 | Uplink SINR estimation |
AU2003227004A AU2003227004A1 (en) | 2003-01-29 | 2003-01-29 | Uplink sinr estimation |
CNA038258617A CN1736054A (en) | 2003-01-29 | 2003-01-29 | Uplink SINR estimation |
PCT/CN2003/000101 WO2004068779A1 (en) | 2003-01-29 | 2003-01-29 | Uplink sinr estimation |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/CN2003/000101 WO2004068779A1 (en) | 2003-01-29 | 2003-01-29 | Uplink sinr estimation |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2004068779A1 true WO2004068779A1 (en) | 2004-08-12 |
Family
ID=32778643
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/CN2003/000101 WO2004068779A1 (en) | 2003-01-29 | 2003-01-29 | Uplink sinr estimation |
Country Status (6)
Country | Link |
---|---|
EP (1) | EP1590911A4 (en) |
JP (1) | JP2006514452A (en) |
CN (1) | CN1736054A (en) |
AU (1) | AU2003227004A1 (en) |
CA (1) | CA2513318A1 (en) |
WO (1) | WO2004068779A1 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2007096799A1 (en) * | 2006-02-22 | 2007-08-30 | Nxp B.V. | A symbol-level adaptation method, memory, equalizer and receiver for implementing this method |
CN101588590B (en) * | 2008-05-20 | 2011-04-27 | ***通信集团公司 | Method and device for estimating channel quality of uplink data channels |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7561615B2 (en) * | 2005-03-18 | 2009-07-14 | Interdigital Technology Corporation | Method and apparatus for compensating for phase noise of symbols spread with a long spreading code |
US8699553B2 (en) * | 2010-02-19 | 2014-04-15 | Telefonaktiebolaget Lm Ericsson (Publ) | Data-aided SIR estimation |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1998051030A1 (en) * | 1997-05-01 | 1998-11-12 | Northern Telecom Limited | Method and system for determining signal to interference plus noise power ratio (sinr) in a communications system |
WO2000054427A1 (en) * | 1999-03-10 | 2000-09-14 | Nokia Mobile Phones Ltd. | Adaptive channel equalizer |
WO2000057654A2 (en) * | 1999-03-19 | 2000-09-28 | Telefonaktiebolaget Lm Ericsson (Publ) | Code reservation for interference measurement in a cdma radiocommunication system |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3457357B2 (en) * | 1993-07-23 | 2003-10-14 | 株式会社日立製作所 | Spread spectrum communication system, transmission power control method, mobile terminal device, and base station |
US6373878B1 (en) * | 1998-11-02 | 2002-04-16 | Telefonaktiebolaget Lm Ericsson (Publ) | Using a fast AGC as part of SIR calculation |
KR100346227B1 (en) * | 1999-09-18 | 2002-08-01 | 삼성전자 주식회사 | Apparatus and method for noise power estimation in cdma mobile communication system |
-
2003
- 2003-01-29 WO PCT/CN2003/000101 patent/WO2004068779A1/en not_active Application Discontinuation
- 2003-01-29 CA CA002513318A patent/CA2513318A1/en not_active Abandoned
- 2003-01-29 CN CNA038258617A patent/CN1736054A/en active Pending
- 2003-01-29 JP JP2004567218A patent/JP2006514452A/en active Pending
- 2003-01-29 AU AU2003227004A patent/AU2003227004A1/en not_active Abandoned
- 2003-01-29 EP EP03815510A patent/EP1590911A4/en not_active Withdrawn
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1998051030A1 (en) * | 1997-05-01 | 1998-11-12 | Northern Telecom Limited | Method and system for determining signal to interference plus noise power ratio (sinr) in a communications system |
WO2000054427A1 (en) * | 1999-03-10 | 2000-09-14 | Nokia Mobile Phones Ltd. | Adaptive channel equalizer |
WO2000057654A2 (en) * | 1999-03-19 | 2000-09-28 | Telefonaktiebolaget Lm Ericsson (Publ) | Code reservation for interference measurement in a cdma radiocommunication system |
Non-Patent Citations (1)
Title |
---|
See also references of EP1590911A4 * |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2007096799A1 (en) * | 2006-02-22 | 2007-08-30 | Nxp B.V. | A symbol-level adaptation method, memory, equalizer and receiver for implementing this method |
JP2009527967A (en) * | 2006-02-22 | 2009-07-30 | エヌエックスピー ビー ヴィ | Symbol-level adaptation method and memory, equalizer, receiver for implementing the method |
US8208457B2 (en) | 2006-02-22 | 2012-06-26 | St-Ericsson Sa | Symbol-level adaptation method, memory, equalizer and receiver for implementing this method |
CN101588590B (en) * | 2008-05-20 | 2011-04-27 | ***通信集团公司 | Method and device for estimating channel quality of uplink data channels |
Also Published As
Publication number | Publication date |
---|---|
CA2513318A1 (en) | 2004-08-12 |
CN1736054A (en) | 2006-02-15 |
JP2006514452A (en) | 2006-04-27 |
AU2003227004A1 (en) | 2004-08-23 |
EP1590911A4 (en) | 2008-05-28 |
EP1590911A1 (en) | 2005-11-02 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP4574924B2 (en) | Method and apparatus for determining a closed loop power control set point in a wireless packet data communication system | |
US7356071B2 (en) | Method and apparatus for estimating signal-to-noise ratio based on dedicated physical channel pilot symbols | |
RU2233548C2 (en) | Device and method for evaluating burst data transfer speed in mobile communication system | |
KR100888188B1 (en) | Method and apparatus for improving noise power estimate in wcdma network | |
US7848389B2 (en) | Method and apparatus for scaling parameter estimation in parametric generalized rake receivers | |
KR100617674B1 (en) | Multiple walsh code demodulator using chip combiner and method thereof | |
JP3759963B2 (en) | Variable rate transmission method, reception method, variable rate transmission device, and reception device | |
US7889782B2 (en) | Joint de-spreading and frequency correction using a correlator | |
US8576963B2 (en) | Non-coherent detection apparatus and method for IEEE 802.15.4 LR-WPAN BPSK receiver | |
US20040264604A1 (en) | Unbiased signal to interference ratio in wireless communications devices and methods therefor | |
EP2127117A2 (en) | Mmse channel estimation in a communications receiver | |
KR20000006161A (en) | Apparatus and method for measuring non-orthogonal noise in cdma communication system | |
US20040252793A1 (en) | Channel estimation method and apparatus | |
US20030053522A1 (en) | Method and device for estimating a channel propagation | |
US20060154633A1 (en) | Uplink sinr estimation | |
US20030156563A1 (en) | Data signal demodulation in a communication system | |
US7489732B2 (en) | Decreasing computational complexity of TD-SCDMA measurement process | |
US6674792B1 (en) | Demodulation of receiver with simple structure | |
KR100699388B1 (en) | Processor and method for weight detection in a closed loop wcdma system with multipath diversity | |
WO2004068779A1 (en) | Uplink sinr estimation | |
US20020131483A1 (en) | Spreading factor estimation system and method | |
JP3886748B2 (en) | Demodulator, demodulation method, and communication apparatus | |
KR100386569B1 (en) | channel estimation method, and apparatus for the same | |
EP1225708A2 (en) | Spreading factor estimation system and method | |
JP2001223621A (en) | Receiver |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ OM PH PL PT RO RU SC SD SE SG SK SL TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LU MC NL PT SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
DFPE | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101) | ||
WWE | Wipo information: entry into national phase |
Ref document number: 2513318 Country of ref document: CA |
|
WWE | Wipo information: entry into national phase |
Ref document number: 3138/DELNP/2005 Country of ref document: IN |
|
WWE | Wipo information: entry into national phase |
Ref document number: 20038258617 Country of ref document: CN |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2003815510 Country of ref document: EP Ref document number: 2004567218 Country of ref document: JP |
|
WWP | Wipo information: published in national office |
Ref document number: 2003815510 Country of ref document: EP |
|
ENP | Entry into the national phase |
Ref document number: 2006154633 Country of ref document: US Kind code of ref document: A1 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 10542535 Country of ref document: US |
|
WWP | Wipo information: published in national office |
Ref document number: 10542535 Country of ref document: US |
|
WWW | Wipo information: withdrawn in national office |
Ref document number: 2003815510 Country of ref document: EP |