GB2502344A

GB2502344A - Signal to noise and interference ratio estimation of data received at an iterative receiver

Info

Publication number: GB2502344A
Application number: GB1209248.2A
Authority: GB
Inventors: Olga Kayo
Original assignee: Renesas Mobile Corp
Current assignee: Renesas Electronics Corp
Priority date: 2012-05-25
Filing date: 2012-05-25
Publication date: 2013-11-27
Anticipated expiration: 2032-05-25
Also published as: GB201209248D0; GB2502344B

Abstract

A method, apparatus and computer program are provided for signal to noise and interference ratio (SNIR) and channel quality estimation. A signal to noise and interference ratio for a first round of processing of data received at an iterative receiver is determined (502). An estimation for a signal to noise and interference ratio for a second round of processing of the data received at the iterative receiver is made based on a change (Î ) (504). A channel quality measure can be estimated for the second round of processing based on the estimated signal to noise and interference ratio for the second round of processing based on the change (Î ). The change (Î ) may be based on a difference between the signal to noise and interference ratio to channel quality indication mapping for the iterative receiver and the signal to noise and interference ratio to channel quality indication mapping for a non-iterative receiver.

Description

METHOD, APPARATUS AND COMPUTER PROGRAM FOR

SIGNAL TO NOISE AND INTERFERENCE RATIO ESTIMATION

Technical Field

S The present invention relates to a method, apparatus and a computer program for signal to noise and interference ratio estimation. Embodiments of the present invention relate generally to communications teclmology and particular embodiments relate to channel quality estimation.

Background

In some examples, link adaptation is used in communications technology, such as High-Speed Downlink racket Access (FISDPA), in an instance in which fast power control operations are unavailable or not used in a particular implementation. Link adaptation is configured, in some examples, to select a suitable combination of channel codes, codes rates, modulation, physical layer retransmission and/or the lilce.

Link adaptation may be performed based on a received channel quality indication (CQI) report that is, for example, transmitted via an uplink (UL) physical layer feedback information element from a communication device, such as user equipment, to an access point.

In an instance in which a communication device includes or is embodied as an iterative receiver, several iterations may be involved in order to process data that is received. Therefore, because of the processing time of each of the iterations, the communication device may not be able to estimate a CQI for a second round or iteration in the time period provided by current specifications, such as 3rd Generation Partnership Project (3GPP) TS 25.214, Subchapter 6A.2, which is incorporated by reference herein. In other words and by way of example, a communications device may not able to calculate and/or transmit a CQI from the second round or iteration for the iterative receiver within the timing restrictions in an instance in which the communication device is operating in a link adaptation environment.

Summary

According to a first aspect of the present invention, there is provided a method for estimating a signal to noise and interference ratio, the method comprising: determining a signal to noise and interference ratio for a first round of processing of S data received at an iterative receiver; and determining an estimation for a signal to noise and interference ratio for a second round of processing of the data received at the iterative receiver based on a change (A). Alternatively or additionally, other qualitative/quantitative measures reflecting an ability of a receiver to process data may also be estimated.

According to a second aspect of the present invention, there is provided apparatus for estimating a signal to noise and interference ratio, the apparatus comprising: a processing system arranged to cause the apparatus to at least: determine a signal to noise and interference ratio for a first round of processing of data received at an iterative receiver; and determine an estimation for a signal to noise and interference ratio for a second round of processing of the data received at the iterative receiver based on a change (A).

According to a third aspect of the present invention, there is provided a computer program for estimating a signal to noise and interference ratio comprising a set of instructions, which, when cxecutcd on an apparatus causes the apparatus to perform the steps of: determining a signal to noise and interference ratio for a first round of processing of data received at an iterative receiver; and determining an estimation for a signal to noise and interference ratio for a second round of processing of the data received at the iterative receiver based on a change (A).

According to a fourth aspect of the present invention, there is provided apparatus for estimating a signal to noise and interference ratio, the apparatus comprising: means for determining a signal to noise and interference ratio for a fir st round of processing of data received at an iterative receiver; and means for determining an estimation for a signal to noise and interference ratio for a second round of processing of the data received at the iterative receiver based on a change (A).

The processing system described above may comprise at least one processor and at least one memory including computer program code with the at least one memory and the computer program code being configured, with the at least one processor, to cause the apparatus to at least operate as described above.

Thcrc may be provided a computcr program product that includes at least onc non-transitory computer-readable storage medium having the computer-readable program instructions described above stored therein.

Further features and advantages of the invention will become apparent from the Ibilowing description of preferred embodiments of the invention, given by way of example only, which is made with reference to the accompanying drawings.

Brief Deserintion of the Dntwinns Figure 1 shows a schematic representation of a system having, fin example, at least one communication device that may benefit from some example embodiments of the present invention; Figure 2 shows a block diagram of an apparatus that may be embodied by a communication device in accordance with some example embodiments of the present invention; Figure 3 shows a diagram illustrating an example of signal mapping tables lbr an iterative and a non-iterative receiver, in accordance with some example embodiments of the present invention; Figures 4a and 4b show diagrams illustrating examples of approximation ofa delta, in accordance with some example embodiments of the present invention; and Figures 5 to 7 show flow charts illustrating operations performed by an example communication device, in accordance with some example embodiments of the present invention.

S

Detailed Description

Examples of embodiments of the present invention will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the invention arc shown. Indccd, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.

As used in this specification, the term "circuitry" refers to all of the following: (a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and (b) to combinations of circuits and software (ancL/or firmware), such as (as applicable): (i) to a combination of processor(s) or (ii) to portions of processor(s)/software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and (c) to circuits, such as a microprocessor(s) or a portion of a microprocessor(s), that require software or firmware for operation, even if the software or firmware is not physically present.

This definition of "circuitry" applies to all uses of this term in this specification, including in any claims. As a further example, as used in this specification, the term "circuitry" would also cover an implementation of merely a processor (or multiple processors) or portion of a processor and its (or their) accompanying software and/or firmware. The term "circuitry" would also cover, for example and if applicable to the particular claim element, a baseband integrated circuit or application specific integrated circuit for a mobile phone or a similar integrated circuit in server, a cellular network device, or other network device.

As is disclosed herein, signal to noise ratio (SNR), signal to interference ratio (SIR) and/or signal to interference plus noise ratio (SINR) may be used interchangeably and as such the term SINR may be used generically throughout the S disclosure and claims. The term SINR should be construed to cover and or be used interchangeably with SNR and/or SIR. Furthermore, the method, apparatus and computer program product as described herein may be implemented for other quantitative/qualitative measurements of the quality of reception in a receiver.

Although the method, apparatus and computer program product as dcscribcd herein may be implemented in a variety of different systems, one example of such a system is shown schematically in Figure 1, which includes a communication device (e.g. communication device 10) that is capable of communication via an access point 12, such as a base station, a macro ccli, a Node B, an evolved node B (eNB), a coordination unit, a base station or other access point, with a network 14 (e.g. a core network). While the network may be configured in accordance with Long Term Evolution (LTETM) or LTE-Advanced (LTE-ATM), other networks may support the method, apparatus and computer program product of embodiments of the present invention including those configured in accordance with wideband code division multiple access (W-CDMATM), CDMA2000, Global System for Mobile Communications (GSMTM), General Packet Radio Service (GPRSTM), IEEE 802.11 standard for wireless fidelity IWiFiTM), wireless local access network (WLANTM) Worldwide Interoperability for Microwave Access (WiMAXTM) protocols, and/or the like.

The network 14 may include a collection of various different nodes, devices or functions which may be in communication with each other via corresponding wired and/or wireless interfaces. For example, the network may include one or more cells, including access point 12, and which may serve a respective coverage area. The access point 12 may be, for example, part of one or more cellular or mobile networks or public land mobile networks (PLMNs). In turn, other devices such as processing devices (e.g. personal computers, server computers or the like) may be coupled to the communication device 10 and/or other communication devices via the network.

A communication device, such as the communication device 10 (also known S as user equipment (UE), a mobile terminal or the like), may be in communication with other communication devices or other devices via the access point 12 and, in turn, the network 14. In some eases, the communication device 10 may include an antenna for transmitting signals to and for receiving signals from an access point 12. As is described herein, the communication device 10 may frmnction as an iterative receiver.

In some example embodiments, the communication device 10 may be a mobile communication device such as, for example, a mobile telephone, portable digital assistant (PDA), pager, laptop computer, STA, or any of numerous other hand held or portable communication devices, computation devices, content generation devices, content consumption devices, or combinations thereof As such, the communication device 10 may include one or more processors that may define processing circuitry and a processing system, either alone or in combination with one or more memories. The processing circuitry may utilise instructions stored in the memory to cause the communication device 10 to operate in a particular way or execute specific functionality when the instructions are executed by the one or more processors. The communication device 10 may also include communication circuitry and corresponding hardware/software to enable communication with other devices and/or the network 14.

In one embodiment, for example, the communication device 10 and/or the access point 12 may be embodied as or otherwise include an apparatus 20 as generically represented by the block diagram of Figure 2. While the apparatus 20 may be employed, for example, by a communication device 10 or an access point 12, it should be noted that the components, devices or elements described below may not be mandatory and thus some may be omitted in certain embodiments. Additionally, some embodiments may include further or different components, devices or elements beyond those shown and described herein.

As shown in Figure 2, the apparatus 20 may include or otherwise be in S communication with processing circuitry 22 that is configurable to perform actions in accordance with example embodiments described herein. The processing circuitry may be configured to perform data processing, application execution, SINR to CQI mapping, and/or other processing and management services according to an example embodiment of the present invention. In some embodiments, the apparatus or the processing circuitry may be embodied as a chip or chipset. In other words, the apparatus or the processing circuitry may comprise one or more physical packages (e.g. chips) including materials, components and/or wires on a structural assembly (e.g. a baseboard). The structural assembly may provide physical strength, conservation of size, and/or limitation of electrical interaction for component circuitry included thereon. The apparatus or the processing circuitry 22 may therefore, in some cases, be configured to implement an embodiment of the present invention on a single chip or as a single "system-on-a-chip". As such, in some cases, a chip or chipset may constitute means for performing one or more operations for providing the functionalities described herein. Alternatively or additionally, a processing system may be embodied by or have similar functionality to the processing circuitry 22.

In an example embodiment, the processing circuitry 22 may include a processor 24 and memory 26 that may be in communication with or otherwise control a communication interface 30 and, in some cases, a user interface 28. As such, the processing circuitry 22 may be embodied as a circuit chip (e.g. an integrated circuit chip) configured (e.g. with hardware, software or a combination of hardware and software) to perform operations described herein. However, in some embodiments taken in the context of the communication device 10, the processing circuitry 22 may be embodied as a portion of a mobile computing device or other communication device.

S

Thc uscr intcrfacc 28 (if implemcnted) may be in communication with the processing circuitry 22 to receive an indication of a user input at the user interfacc and/or to provide an audible, visual, mechanical or other output to the user. As such, the user interface may include, for example, a keyboard, a mouse, a trackball, a S display, a touch screen, a microphone, a speaker, and/or other input/output mechanisms. The apparatus 20 need not always include a user interface.

The communication interface 30 may include one or more interface mcchanisms for enabling communication with other devices andior nctworks. In some cases, the communication intcrfacc may bc any mcans such as a dcvicc or circuitry embodied in either hardware, or a combinatioll of hardware and software that is configured to receive and/or transmit data from/to a network 1 6 and/or any other dcvice or module in communication with thc proccssing circuitry 22, such as bctween thc access point 12 and thc communication dcvice 10. In somc cxample embodiments, the communications interface 30 may include an iterative receiver 32 andior a non-iterative receiver 34 which may be in communications with or otherwise interact with the processing circuitry 22. The iterative receiver 32 may be configured to perform one or more rounds or iterations to process received data, whereas the non-iterative receiver 34 may be configured to process received communications in a single iteration. Further, the communication interface 30 may include, for example, an antenna (or multiple antennas) and supporting hardware andior softwarc for enabling communications with a wireless communicatioll network and/or a communication modem or other hardware/software for supporting communication via cable, digital subscriber line (DSL), universal serial bus (USB), Ethernet or other methods.

In an example embodiment, the memory 26 may include one or more non-transitory memory devices such as, for example, volatile andior non-volatile memory that may be either fixed or removable. The memory 26 may be configured to store information, data, applications, instructiolls or the like for enabling the apparatus 20 to carry out various functions in accordance with example embodiments of the present invention. For example, the memory 26 may be configured to buffer input data for processing by the processor 24. Additionally or a!ternativdy, the memory 26 could be configured to store instructions for execution by the processor 24. As yet another ahernative, the memory 26 may include one of a plurality of databases that may store S a variety of files, mapping tables, contents or data sets. Among the contents of the memory 26, applications may be stored for execution by the processor in order to carry out the functionality associated with each respective application. In some cases, the memory 26 may be in communication with the processor 24 via a bus for passing information among components of the apparatus.

The processor 24 may be embodied in a number of different ways. For example, the processor 24 may be embodied as various processing means such as one or more of a microprocessor or other processing element, a coproccssor, a controller or various other computing or processing devices induding integrated circuits such as, for example, an ASIC (application specific integrated circuit), an FPGA (field programmable gate array), or the like. In an example embodiment, the processor may be configured to execute instructions stored in the memory 26 or otheiise accessible to the processor. As such, whether configured by hardware or by a combination of hardware and software, the processor may represent an entity (e.g. physically embodied in circuitry -in the form of processing circuitry 22) capable of performing operations according to embodiments of the present invention while configured accordingly. Thus, for example, when the processor is embodied as an ASIC, FPGA or the like, the processor may be specifically configured hardware for conducting the operations described herein. Alternatively, as another example, when the processor is embodied as an executor of software instructions, the instructions may specifically configure the processor to perform the operations described herein.

In some example embodiments, the communications device 10, such as by the processing circuitry 22, the processor 24 or the like, may be configured to estimate an SINR for a second round or iteration in an iterative receiver, such as iterative receiver 32. As is described herein, an iteration may comprise a single round of processing.

However in alternative example embodiments, an iteration may comprise a plurality of rounds of processing. An STNR of the second round or iteration may be estimated based on a determined SINR for a first round or iteration in the iterative receiver 32 and a determined and/or approximated delta or change (A). The SINR estimate in a second round or iteration may be calculated based on the following non-limiting

example equation:

SINRrouid2 = SlNRroundl + A [dB]. (1) In some example embodiments, the delta (A) or the estimated difference between an SINR calculated for a first round and an SINR calculated for a second round may be detcrmined, such as by the processing circuitry 22, the processor 24 or the like, and may be based on a functional approximation or alternatively may be based on an estimation derived from a previous CQI estimation period or any other reference periods used to estimate the channel reception. A CQI or other channel quality measure may then be estimated based on the estimated SINR for the second round.

In example functional approximation embodiments, a second round SINR may be considered as a function of the first round SINR and the delta (A), for example: SINRround2 = f(SlNRroundl,A) [dBI. (2) In some example embodiments, the communication device 10, such as by the processing circuitry 22, the processor 24 or the like, may be configured to determine SINR to CQI mapping tables, where the SINR to CQI mapping tables may be configured to be tunable for a particular receiver (e.g. iterative receiver 32 and/or non-iterative receiver 34) in the communications device 10. Example SINR to CQI mapping tables arc shown with respect to Figure 3. As is shown in Figure 3 and by way of example, for the same SINR, the iterative receiver may have a higher CQI than that of a non-iterative receiver. The SINR to CQI mapping table may then be used to estimate the CQI for a second round, based on the estimated SINR for the second round, such as by using by Equation (2).

In order to build the SINR to CQI mapping tables, the processing circuitry 22, the processor 24, the communications interface 30, the iterative receiver 32, the non-iterative receiver 34 or the like, may be configured to determine an SINR for many, if not all, fixed CQI values within a wide range of channel geometry. In some example embodiments, an SINR may be determined for each CQI value that fttlfihls an example 10% block crror ratc (BLER) condition, such as thc BLER condition highlighted in 3GPP TS 25.214. For example, a BLER condition may be based on an unrestricted observation interval and the communication device, such as communications device 10. The communication device 10 may be configured to report the highest tabulated CQI value for which a single High-Speed Downlink Shared Channel (HS-DSCH) sub-frame formatted with the transport block size, number of High Speed-Physical Downlink Shared Channel (HS-PDSCH) codes and modulation corresponding to the reported or lower CQI value could be received such as to achieve a transport block error probability not exceeding 0.1 in a 3-slot reference period ending 1 slot before the start of the first slot in which the reported CQI value is transmitted.

In some example embodiments, the processing circuitry 22, the processor 24 or the like may be configured to determine the difference between the determined SINR values for the iterative receiver from those determined SINR values for the non-iterative receiver. The differences between the SINRs, as illustrated in Figure 3, may be used to generate the delta (A). An example of a calculated delta (A) across SINR values is shown with reference to Figure 4a.

In some example embodiments, the delta (A) may be approximated, such as by the processing circuitry 22, the processor 24 or the like, by a sum of the SINR, such as a mean of the calculated delta (A) shown with respect to Figure 4a, and a constant (e.g. linear function) or complex (e.g. quadratic, cubic, polynomial etc.) function of SINR. In some example embodiments, the delta (A) may be approximated by a constant a (found, for example, as the mean of the calculated (A) shown with respect to Figure 4a; a could be selected to be a minimum possible (A) shown with respect to Figure 4a, and/or the like). In such cases, the SINRroflfldz = f (SINR1ojn1, A) [dB] (2) may, for example, become: SINRroui1d2 = SlNRroundl + a [dB]. (3) By way of further example, in an instance in rhich a linear approximation for delta (A) is chosen, for example: A= ax + b, where x = SlNRroundl, then the SINRVOUfld2 = f(SINR,.011i, A) [dB] (2) may, for example, become: SINRround2 = (a + 1) SlNRroufldl + b [dB]. (4) For example and as shown with respect to Figure 4b, linear approximation may be approximated by a line delta, for example A = 0.0514 SlNROUldl + 1.1286. These example values are derived based on a least squares function approximation, where the distance between points and the line is found to be minimal.

Alternatively or additionally, other polynomials may be used in some example embodiments. The processing circuitry 22, the processor 24 or the like may determine the formula used to calculate delta (A) and may be further configured to determine, as a result of tuning, the SINR-to-CQI mapping tables for each receiver.

As such, the processing circuitry 22, the processor 24 or the like may continually analyse the polynomial approximation of delta (A) in order for example to reduce a BLER, or to increase throughput, etc. In some example embodiments, delta (A) may be estimated, for a current estimation pcriod (t) such as by thc processing circuitry 22, the proccssor 24 or the likc, bascd on calculated SINRs (SINRroufldl, S1NRroind2) from a prcvious CQI estimation period (e.g. t -1). For example: A(t) = SlNRround7(t -1) -SlNRroundl(t -1) [dB]. (5) The obtained delta (A) from equation (5) may then be used for the second round SINR estimation of the current CQI estimation period. For example: SINRround2(t) = SlNRroundl(t) + a(t) [dB]. (6) In some example embodiments, the first round SINR and the estimation of the second round SIN R as described with respect to SINRroufldz (t) = SINRroundl (t) + (t) [dB] (6) maybe determined in order to cause a transmission of an estimated CQI to the network, such as access point 12, within the timing defined by the specification.

However, in some examples, the second round SINR may also be calculated, such as by the processing circuitry 22, the processor 24 or the like, for the purposes of storing, for example in the memory 26. The second round SINR value may advantageously, for example, be used to estimate a delta (A) for a next or future CQI estimation period.

Alternatively or additionally, equations 3 and 4 may be used in different environments or on different channels from those used with respect to equations 5 and 6. For example, a delta calculated using a previous CQI estimation period, such as described by equations 5 and 6 may result in a smaller BLER, whereas an approximated delta, as shown with respect to equations 3 and 4, may result in a higher BLER, for example. Additionally, for a fast changing environment, where the receiver has to quickly adapt to the changes, the method described with equations S and 6 may be used in some example embodiments. As such, in some example embodiments, the communications device, such as by the processing circuitry 22, the processor 24 or the like, may be configured to determine whether to use delta approximation or previous CQI estimation based on geometry values (G) and or a calculated CQI. Alternatively or additionally, finite impulse response (FIR) or infinite impulse response (IIR) filters may also be used for the estimation of the delta.

Figures 5 to 7 illustrate example operations performed by a method, apparatus and computer program product, such as apparatus 20 of Figure 2 in accordance with one embodiment of the present invention. It will be understood that each block of the flowcharts, and combinations of blocks in the flowcharts, may be implemented by various means, such as hardware, firmware, processor, circuitry and/or other device associated with execution of software including one or more computer program instructions. For example, one or more of the procedures described above may be embodied by computer program instructions. In this regard, the computer program instructions, which embody the procedures described above, may be stored by a memory 26 of an apparatus employing an embodiment of the present invcntion and executed by a processor 24 in the apparatus. As will be appreciated, any such computer program instructions may be loaded onto a computer or other programmable apparatus (e.g. hardware) to produce a machine, such that the resulting computer or other programmable apparatus provides for implementation of the functions specified in the flowcharts' block(s). These computer program instructions may also be stored in a non-transitory computer-readable storage memory that may direct a computer or other programmable apparatus to function in a particular manner, such that the instructions stored in the computer-readable storage memory produce an article of manufacture, the execution of which implements the function specified in the flowcharts' block(s). The computer program instructions may also be loaded onto a computer or other programmable apparatus to cause a series of operations to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide operations for implementing the functions specified in the flowcharts' block(s). As such, the operations of Figures 5 to 7, when executed, convert a computer or processing circuitry into a particular machine configured to perform an example embodiment of the present invention. Accordingly, the operations of Figures 5 to 7 may be regarded as defining an algorithm for configuring a computer or processing circuitry 22, e.g. a processor, to perform an example embodiment. In some cases, a general purpose computer may be provided with an instance of the processor which performs the algorithm of Figures 5 to 7 to transform the general purpose computer into a particular machine configured to perform an example embodiment.

Accordingly, blocks of the flowcharts support combinations of means for S performing the specified functions and combinations of operations for performing the specified functions. It will also be understood that one or more blocks of the flowchart, and combinations of blocks in the flowcharts, can be implemented by special purpose hardware-based computer systems which perform thc specified functions, or combinations of spccial purpose hardwarc and computcr instructions.

In some embodiments, certain ones of the operations above may be modified or further amplified as described below. Moreover, in some embodiments, additional optional operations may also be included. It should be appreciated that each of the modifications, optional additions or amplifications below may be included with the operations above either alone or in combination with any others among the features described herein.

Figure 5 shows a flow chart illustrating an example of operations performed by communication device 10, such as by the processing circuitry 22, the processor 24, the communication interface 30 or the like, in accordance with some example embodiments of the present invention. In some example embodiments, the apparatus embodied, for example, by communication device 10 or part of the communication device is configured to estimate an SINR for a second round or iteration in an iterative receiver, such as iterative receiver 32.

At operation 502, the apparatus 20 embodied, for example, by communication device 10, may include means, such as the processing circuitry 22, the processor 24, or the like, for determining a signal to noise and interference ratio for a first round of processing of data received at an iterative receiver. At operation 504, the apparatus 20 embodied, for example, by communication device 10, may include means, such as the processing circuitry 22, the processor 24 or the like, for determining an estimation for a signal to noise and interference ratio for a second round of processing of the data received at the iterative receiver based on a change (A). At operation 506, the apparatus 20 embodied, for example, by communication device 10, may include means, such as the processing circuitry 22, the processor 24, the communication interface 30, or the like, for causing a channel quality measure to be estimated for the second round of processing based on the estimated signal to noise and interference ratio for the second round of processing.

Figurc 6 shows a flow chart illustrating an example of operations performed by an example communication device 10, such as by the proccssing circuitry 22, the processor 24, the communication interface 30 or the like, in accordance with some example embodiments of the present invention. In some example embodiments, the apparatus 20 embodied, for example, by communication device 10, may be configured to determine a delta (A) based on an approximation.

At operation 602, the apparatus 20 embodied, for example, by an example communication device 10, may include means, such as the processing circuitry 22, the processor 24 or the like, for determining a signal to noise and interference ratio to channel quality measure mapping for an iterative receiver, such as iterative receiver 32. At operation 604, the apparatus 20 embodied, for example, by an example communication devicc 10, may includc means, such as the processing circuitry 22, the processor 24 or the like, for determining a signal to noise and interference ratio to channel quality indication mapping for a non-iterative receiver. At operation 606, the apparatus 20 embodied, for example, by an example communication device 10, may include means, such as the processing circuitry 22, the processor 24 or the like, for determining the change (A) for a signal to noise and interference ratio based on a difference between the signal to noise and interference ratio to channel quality indication mapping for the iterative receiver and the signal to noise and interference ratio to channel quality indication mapping for the non-iterative receiver. Operation 606, in some example embodiments may be accomplished during a tuning phase, but in alternative example embodiments may occur constantly, at a known interval, or the like.

Figure 7 shows a flow chart illustrating an example of operations performed S by an example communication device 10, such as by the processing circuitry 22, the processor 24, the communication interface 30 or the like, in accordance with some example embodiments of the present invention. In some example embodiments, the apparatus 20 embodied, for example, by communication device 10, may be configured to determine a delta (A) bascd on a prior SINR cstimation.

At operation 702, the apparatus 20 embodied, for example, by an example communication device 10, may include means, such as the processing circuitry 22, the processor 24 or the like, for the change (A) for a current CQI estimation period based on a determined difference between an SINR for a first round and an SINR for a second round of a previous CQI estimation period. At operation 704, the apparatus 20 embodied, for example, by an example communication device 10, may include means, such as the processing circuitry 22, the processor 24 or the like, for causing a channel quality measure to be estimated for a second round of processing based on the change (A).

Many modifications and other cmbodimcnts of the invention sct forth herein will come to mind to one skilled in the art to which this invention pertains having the benefit of the teachings presented in the foregoing description and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Moreover, although the foregoing description and the associated drawings describe example embodiments in the context of certain example combinations of elements andior ftinctions, it should be appreciated that different combinations of elements and/or flmctions may be provided by alternative embodiments without departing from the scope of the appended claims. In this regard, for example, different combinations of elements and/or ftmnct ions than those explicitly described above are also contemplated as may be set forth in some of the appended claims. Although specific tcrms arc employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

S

The above embodiments are to be understood as illustrative examples of the invention. Further embodiments of the invention are envisaged. It is to be understood that any feature described in relation to any one embodiment may be used alone, or in combination with othcr features described, and may also be used in combination with one or more features of any other of the embodiments, or any combination of any other of the embodiments. Furthermore, equivalents and modifications not described above may also be employed without departing from the scope of the invention, which is defined in the accompanying claims.

Claims

CLAIMS1. A method for estimating a signal to noise and interference ratio, the method comprising: S determining a signal to noise and interference ratio for a first round of processing of data received at an iterative receiver; and determining an estimation for a signal to noise and interference ratio for a second round of processing of the data received at the iterative receiver based on a change (A).
2. A method according to claim 1, comprising: causing a channel quality measure to be estimated for the second round of proccssing bascd on thc estimated signal to noisc and interfcrence ratio for the sccond round of processing bascd on thc changc (A).
3. A method according to claim I or claim 2, comprising: determining a signal to noise and interference ratio to channel quality indication mapping for the iterative receiver; determining a signal to noise and interference ratio to channel quality indication mapping for a non-iterative receiver; and determining the change (A) for a signal to noisc and interferencc ratio based on a difference between the signal to noise and interference ratio to channel quality indication mapping for the iterative receiver and the signal to noise and interference ratio to channel quality indication mapping for the non-iterative receiver.
4. A method according to any of claims I to 3, wherein the second round of processing occurs after the channel quality indication is estimated.
5. A method according to any of claims ito 4, wherein the signal to noise and interference ratio for the second round of processing is a function of the signal to noise and interference ratio of the first round of processing and the change (A).
6. A method according to claim 5, wherein the function comprises SlNRrouid2 = f(SINRroundl) [dB], where SINRrOIIIId2 is the signal to noise and interference ratio for the second round of processing and SlNRroufldl is the signal to noise and interference ratio for the first round of processing.
7. A method according to any of claims I to 6, wherein the change (A) is approximated by a constant (a) where A= a.
8. A method according to any of claims 1 to 6, wherein the change (A) is approximated by at east one of a linear approximation, a quadratic approximation or a cubic approximation.
9. A method according to claim 8, wherein the linear approximation is determined based on A= ax + b and x = SINRrouidl.
10. A method according to any of claims 1 to 6, wherein the change (A) is estimated by the signal to noise and interference ratio for the first round of processing (SlNRroijndl) and the signal to noise and interference ratio for the second round of processing (SINRI.OUfld2) from a prior channel quality indication period (t-1), such that A(t) = S1NRrOLIld2 (t -1) -SlNRroLIldl(t -1) [dB].
11. A method according to claim 10, comprising: determining an estimated signal to noise and interference ratio for the second round of processing based on 12. Apparatus for estimating a signal to noise and interference ratio, the apparatus comprising: a processing system arranged to cause the apparatus to at least: determine a signal to noise and interference ratio for a first round of processing of data received at an iterative receiver; and detcrminc an estimation for a signal to noise and interference ratio for a sccond round ofproccssing of the data rcccivcd at thc iterative rcceivcr bascd on a change (A).13. Apparatus according to claim 12, wherein the processing system is arranged to cause the apparatus to: cause a channel quality measure to be estimated for the second round of processing based on the estimated signal to noise and interference ratio for the second round of proccssing based on the change (A).14. Apparatus according to any claim 12 or claim 13, wherein the processing system is arranged to cause the apparatus to: detcrminc a signal to noisc and interfcrencc ratio to channel quality indication mapping for thc itcrativc receiver; determine a signal to noise and interference ratio to channel quality indication mapping for a non-iterative receiver; and determine the change (A) for a signal to noise and interference ratio based on a difference between the signal to noise and interference ratio to channel quality indication mapping for the iterative receiver and the signal to noise and interference ratio to channel quality indication mapping for the non-iterative receiver.15. Apparatus according to any of claims 12 to 14, wherein the second round of processing occurs after the channel quality indication is estimated.16. Apparatus according to any of claims 12 to 15, wherein the signal to noise and interference ratio for the second round of processing is a function of the signal to noise and interference ratio of the first round of processing and the change (A).17. Apparatus according to claim 16, wherein the function comprises SlNRround2 = f(S1NRrotndl,A) [dB], where SlNRroufld2 is an estimate of the signal to noise and interference ratio for the second round of processing and SIN Rroundl is the signal to noise and interference ratio for the first round of processing.18. Apparatus according to any of claims 12 to 17, whcrcin thc change (A) is S estimated by a constant (a) where = a.19. Apparatus according to any of claims 12 to 17, wherein the change (A) is estimated by at least one of a linear approximation, a quadratic approximation or a cubic approximation.20. Apparatus according to claim 19, wherein the linear approximation is determined based on A= ax + b and x = SlNRroufldl.21. Apparatus according to any of claims 12 to 17, wherein the change (A) is estimated by the signal to noise and interference ratio for thc first round ofproccssing (SlNROUldl) and the signal to noisc and intcrfcrcncc ratio for thc sccond round of processing (SINRrouid2) from a prior channel quality indication period (I-i), such that = SlNRround2 (t -1) -SINRroundl (t -1) [dB].22. Apparatus according to claim 21, wherein the processing system is arranged to cause the apparatus to: determine an estimated signal to noise and interference ratio for the second round of processing based on 23. Apparatus according to any of claims 12 to 22, wherein the apparatus comprises at least one of an access point, user equipment or a communications device.24. Apparatus according to any of claims 12 to 23, wherein the apparatus is configured for usc in at Icast onc of a widcband codc division multiplc access, a timc division synchronous code division multiple access, a Long Term Evolution or a Long Term Evolution Advanced system.25. A computer program for estimating a signal to noise and interference ratio comprising a set of instructions, which, when executed on an apparatus causes the apparatus to perform the steps of: determining a signal to noise and interference ratio for a first round of processing of data received at an iterative receiver; and determining an estimation for a signal to noise and interference ratio for a second round of processing of the data received at the iterative receiver based on a change (A).26. A computer program according to claim 25, comprising instructions, which, when executed on the apparatus causes the apparatus to perform the step of: causing a channel quality measure to be estimated for the second round of processing based on the estimated signal to noise and interference ratio for the second round of processing based on the change (A).27. A computer program according to any claim 25 or claim 26, comprising instructions, which, when executed on the apparatus causes the apparatus to perform the step of: determining a signal to noise and interference ratio to channel quality indication mapping for the iterative receiver; determining a signal to noise and interference ratio to channel quality indication mapping for a non-iterative receiver; and determining the change (A) for a signal to noise and interference ratio based on a difference between the signal to noise and interference ratio to channel quality indication mapping for the iterative receiver and the signal to noise and interference ratio to channel quality indication mapping for the non-iterative receiver.28. A computer program according to any of claims 25 to 27, wherein the second round of processing occurs after the channel quality indication is estimated.29. A computer program according to any of claims 25 to 28, wherein the signal to noise and interference ratio for the second round of processing is a ifinction of the signal to noise and interference ratio of the first round of processing and the change (A).S30. A computer program according to claim 29, wherein the function comprises SlNRround2 = f(S1NRrotndl,A) [dB], where SlNRroufld2 is an estimate of the signal to noise and interference ratio for the second round of processing and SIN R01d1 is the signal to noise and interference ratio for the first round of processing.31. A computer program according to any of claims 25 to 30, wherein the change (A) is estimated by a constant (a) where = a.32. A computer program according to any of claims 25 to 30, wherein the change IS (A) is estimated by at least one ofa linear approximation, a quadratic approximation or a cubic approximation.33. A computer program according to claim 32, wherein the linear approximation is determined based on = ax + b and x = SlNRO11fldl.34. A computer program according to any of claims 25 to 30, wherein the change (A) is estimated by the signal to noise and interference ratio for the first round of processing (SlNRroufldl) and the signal to noise and interference ratio for the second round of processing (SINRFOL[11d2) from a prior channel quality indication period (t-1), such that (i) = SINRrouiid2 (t -1) -SlNRrouiidl (1 -1) [dB].35. A computer program according to claim 34, comprising instructions, which, when executed on the apparatus causes the apparatus to perform the step of: dctcrmining an estimated signal to noise and intcrfcrencc ratio for the second round of processing based on 36. Apparatus for estimating a signal to noise and interference ratio, the apparatus comprising: means for determining a signal to noise and interference ratio for a first round of processing of data received at an iterative receiver; and S means for determining an estimation for a signal to noise and interference ratio for a second round of processing of the data received at the iterative receiver based on a change (A).37. Apparatus according to claim 36, comprising: means for causing a channel qualify measurc to be estimated for the second round of processing based on the estimated signal to noise and interference ratio for the second round of processing based on the change (A).38. Apparatus according to any claim 36 or claim 37, comprising: means for determining a signal to noise and interference ratio to channel quality indication mapping for the iterative receiver; means for determining a signal to noise and interference ratio to channel qualify indication mapping for a non-if erative receiver; and means for determining the change (A) for a signal to noise and interference ratio based on a difference between the signal to noise and interference ratio to channel quality indication mapping for the iterative rcccivcr and thc signal to noise and interference ratio to channel quality indication mapping for the non-iterative receiver.39. Apparatus according to any of claims 36 to 38, wherein the second round of processing occurs after the channel quality indication is estimated.40. Apparatus according to any of claims 36 to 39, wherein the signal to noise and interference ratio for the second round of processing is a function of the signal to noise and interference ratio of the first round of processing and the change (A).41. Apparatus according to claim 40, wherein the function comprises SlNRround2 = f(SINRrounaijA) [dB], where SINRrOUnd2 is an estimate of the signal to noise and interference ratio for the second round of processing and SINRrQUfldl s the signal to noise and interference ratio for the first round of processing.42. Apparatus according to any of claims 36 to 41, wherein the change (A) is cstimatcd by a constant (a) where = a.43. Apparatus according to any of claims 36 to 41, wherein the change (A) is estimated by at least one of a linear approximation, a quadratic approximation or a cubic approximation.44. Apparatus according to claim 44, wherein the linear approximation is determined based on ax + b and x = SlNRrouidl.45. Apparatus according to any of claims 36 to 41, wherein the change (A) is estimated by the signal to noise and interference ratio for the first round of processing (SlNR01ai) and the signal to noise and interference ratio for the second round of processing (SINRI.OI1d2) from a prior channel quality indication period (i-i), such that (t = SlNRround2 (t -1) -SINRroundl(t -1) [dB].46. Apparatus according to claim 45, comprising: means for determining an estimated signal to noise and interference ratio for the second round of processing based on A(t.47. Apparatus according to any of claims 36 to 46, wherein the apparatus comprises at least onc of an access point, user equipment or a communications device.48. Apparatus according to any of claims 36 to 47, wherein the apparatus is configured for use in at least one ofa wideband code division multiple access, time division synchronous code division multiple access, a long term evolution or long term evolution advanced system.49. A method of estimating a signal to noise and interference ratio, substantially in S accordance with any of the examples as described herein with reference to and illustrated by the accompanying drawings.50. Apparatus for estimating a signal to noise and intcrfercncc ratio, substantially in accordance with any of thc cxamplcs as described hcrein with rcfcrencc to and illustrated by the accompanying drawings.AMENDMENTS TO THE CLAIMS HAVE BEEN FILED AS FOLLOWSCLAIMS1. A method for estimating a signal to noise and interference ratio, the method eompnsing: determining a signal to noise and interference ratio for a first round of processing of data received at an iterative receiver; and determining an estimation for a signal to noise and interference ratio for a second round of processing of the data received at the iterative receiver based on the determined signal to noise and interference ratio for the first round of processing at the iterative receiver and a change (A).2. A method according to claim 1, comprising: causing a channel quality measure to be estimated for the second round of r processing based on the estimated signal to noise and interference ratio for the second 0 15 round of processing based on the change (A). r3. A method according to claim I or claim 2, comprising: determining a signal to noise and interference ratio to channel quality indication mapping for the iterative receiver; determining a signal to noise and interference ratio to channel quality indication mapping for a non-iterative receiver; and determining the change (A) for a signal to noise and interference ratio based on a difference between the signal to noise and interference ratio to channel quality indication mapping for the iterative receiver and the signal to noise and interference ratio to channel quality indication mapping for the non-iterative receiver.4. A method according to any of claims 1 to 3, wherein the second round of processing occurs after the channel quality indication is estimated.5. A method according to any of claims 1 to 4, wherein the signal to noise and interference ratio for the second round of processing is a function of only the signal to noise and interference ratio of the first round of processing and the change (A).6. A method according to any of claims I to 5, wherein the change (A) is approximated by a constant (a) where A= a.7. A method according to any of claims 1 to 5, wherein the change (A) is approximated by at least one of a linear approximation, a quadratic approximation or a cubic approximation.8. A method according to claim 7, wherein the linear approximation is determined based on A= ax + b and x = SlNRroufldl. r0 15 9. A method according to any of claims 1 to 5, wherein the change (A) is r estimated by the signal to noise and interference ratio for the first round of processing (SlNRroundl) and the signal to noise and interference ratio for the second round of processing (SINRI.OuTld2) from a prior channel quality indication period (t-l), such that A(t) = SINRFOUIId2(t -1) -SlNRIUfldl(t -1) [dB].10. A method according to claim 9, comprising: determining an estimated signal to noise and interference ratio for the second round of processing based on A(t).11. Apparatus for estimating a signal to noise and interference ratio, the apparatus comprising: a processing system arranged to cause the apparatus to at least: determine a signal to noise and interference ratio for a first round of processing of data received at an iterative receiver; and determine an estimation for a signal to noise and interference ratio for a second round of processing of the data received at the iterative receiver based on the determined signal to noise and interference ratio for the first round of processing at the iterative receiver and a change (A).
12. Apparatus according to claim 11, wherein the processing system is arranged to cause the apparatus to: cause a channel quality measure to be estimated for the second round of processing based on the estimated signal to noise and interference ratio for the second round of processing based on the change (A).
13. Apparatus according to claim 11 or claim 12, wherein the processing system is arranged to cause the apparatus to: determine a signal to noise and interference ratio to channel quality indication C\J mapping for the iterative receiver; r determine a signal to noise and interference ratio to channel quality indication 0 15 mapping for a non-iterative receiver; and r. . determine the change (A) for a signal to noise and interference ratio based on a Cr') difference bctwccn thc signal to noise and interference ratio to channel quality indication mapping for the iterative receiver and the signal to noise and interference ratio to channel quality indication mapping for the non-iterative receiver.
14. Apparatus according to any of claims 11 to 13, wherein the second round of processing occurs after the channel quality indication is estimated.
15. Apparatus according to any of claims 11 to 14, wherein the signal to noise and interference ratio for the second round of processing is a thnction of only the signal to noise and interference ratio of the first round of processing and the change (A).
16. Apparatus according to any of claims 11 to 15, wherein the change (A) is estimatcd by a constant (a) where A= a.
17. Apparatus according to any of claims 11 to 15, wherein the change (A) is estimated by at least one of a linear approximation, a quadratic approximation or a cubic approximation.
18. Apparatus according to claim 17, wherein the linear approximation is determined based on ax + b and x = SlNRrouiai.
19. Apparatus according to any of claims 11 to 15, wherein the change (A) is estimated by the signal to noise and interference ratio for the first round of processing (SINRI.QUfldl) and the signal to noise and interference ratio for the second round of processing (SINRroufld2) from a prior channel quality indication period (i-i), such that A(t) = SlNRrouna2(t -1) -S1NRrourai(t -1) [dB]. (420. Apparatus according to claim 19,herein the processing system is arranged to 0 15 cause the apparatus to: determine an estimated signal to noise and interference ratio for the second round of processing based on 21. Apparatus according to any of claims 11 to 20, wherein the apparatus comprises at least one of an access point, user equipment or a communications device.22. Apparatus according to any of claims 11 to 21, wherein the apparatus is configured for use in at least one of a wideband code division multiple access, a time division synchronous code division multiple access, a Long Term Evolution or a Long Term Evolution Advanced system.23. A computer program for estimating a signal to noise and interference ratio comprising a set of instructions, which, when executed on an apparatus causes the apparatus to pcrform the steps of: determining a signal to noise and interference ratio for a first round of processing of data received at an iterative receiver; and determining an estimation for a signal to noise and interference ratio for a second round of processing of the data received at the iterative receiver based on the determined signal to noise and interference ratio for the first round of processing at the iterative receiver and a change (A).24. A computer program according to claim 23, comprising instructions, which, when executed on the apparatus causes the apparatus to perform the step of: causing a channel quality measure to be estimated for the second round of proccssing bascd on thc cstimatcd signal to noisc and intcrfcrcncc ratio for thc sccond round of processing based on the change (A).25. A computer program according to claim 23 or claim 24, comprising C\J instructions, which, when executed on the apparatus causcs the apparatus to pcrform r the step of: 0 15 determining a signal to noise and interference ratio to channel quality r... . indication mapping for the iterative receiver; determining a signal to noise and interference ratio to channel quality indication mapping for a non-iterative receiver; and determining the change (A) for a signal to noise and interference ratio based on a difference between the signal to noise and interference ratio to channel quality indication mapping for the iterative receiver and the signal to noise and interference ratio to channel quality indication mapping for the non-iterative receiver.26. A computer program according to any of claims 23 to 25, wherein the second round of processing occurs after the channel quality indication is estimated.27. A computer program according to any of claims 23 to 26, wherein the signal to noise and interference ratio for the second round of processing is a function of only the signal to noise and interference ratio of the first round of processing and the change (A).28. A computer program according to any of claims 23 to 27, wherein the change (A) is estimated by a constant (a) where = a.29. A computer program according to any of claims 23 to 27, wherein the change S (A) is estimated by at least one of a linear approximation, a quadratic approximation or a cubic approximation.30. A computer program according to claim 29, wherein the linear approximation is deteimined based on i= ax + b and x = SINRroufldl.31. A computer program according to any of claims 23 to 27, wherein the change (A) is estimated by the signal to noise and interference ratio for the first round of C\J processing (SlNRrounai) and the signal to noise and interference ratio for the second r round of processing (SINROUlld2) from a prior channel quality indication period (t-l), 0 15 such that A(t) = SlNRroufld2(t -1) -SlNRroundl(t -1) [dB].32. A computer program according to claim 31, comprising instructions, which, when cxccuted on the apparatus causes the apparatus to pcrform the step of: determining an estimated signal to noise and interference ratio for the second round of processing based on 33. Apparatus for estimating a signal to noise and interference ratio, the apparatus comprising: means for determining a sial to noise and interference ratio for a first round of processing of data received at an iterative receiver; and means for determining an estimation for a signal to noise and interference ratio for a second round of processing of the data received at the iterative receiver based on the determined siwial to noisc and interference ratio for the first round of processing at the iterative receiver and a change (A).34. Apparatus according to claim 33, comprising: means for causing a channel quality measure to be estimated for the second round of processing based on the estimated signal to noise and interference ratio for the second round of processing based on the change (A).35. Apparatus according to claim 33 or claim 34, comprising: means for determining a signal to noise and interference ratio to channel quality indication mapping for the iterative receiver; means for determining a signal to noise and interference ratio to channel quality indication mapping for a non-iterative receiver; and means for determining the change (A) for a signal to noise and interference ratio based on a difference between the signal to noise and interference ratio to channel quality indication mapping for the iterative receiver and the signal to noise and interference ratio to channel quality indication mapping for the non-iterative 1* receiver. or 36. Apparatus according to any of claims 33 to 35, wherein the second round of processing occurs after the channel quality indication is estimated.37. Apparatus according to any of claims 33 to 36, wherein the signal to noise and interference ratio for the second round of processing is a function of only the signal to noise and interference ratio of the first round of processing and the change (A).38. Apparatus according to any of claims 33 to 37, wherein the change (A) is estimated by a constant (a) where A= a.39. Apparatus according to any of claims 33 to 37, wherein the change (A) is estimated by at least one of a linear approximation, a quadratic approximation or a cubic approximation.40. Apparatus according to claim 39, wherein the linear approximation is determined based on A= ax + b and x = SlNR0Ufldl.41. Apparatus according to any of claims 33 to 37, wherein the change (A) is estimated by the signal to noise and interference ratio for the first round of processing (SINRfoL!Idl) and the signal to noise and interference ratio for the second round of S processing (SINRI.OuTld2) from a prior channel quality indication period (t-l), such that A(t) = SINRfQfld2(t -1) -SlNRIUfldl(t -1) [dB].42. Apparatus according to claim 41, comprising: means for determining an estimated signal to noise and interference ratio for the second round of processing based on 43. Apparatus according to any of claims 33 to 42, wherein the apparatus (".1 comprises at least one of an access point, user equipment or a communications device. r0 15 44. Apparatus according to any of claims 33 to 43, wherein the apparatus is configured for use in at least one of a wideband code division multiple access, time division synchronous code division multiple access, a long term evolution or long term evolution advanced system.45. A method of estimating a signal to noise and interference ratio, substantially in accordance with any of the examples as described herein with reference to and illustrated by the accompanying drawings.46. Apparatus for estimating a signal to noise and interference ratio, substantially in accordance with any of the examples as described herein with reference to and illustrated by the accompanying drawings.