阅读说明：本技术 用于小分组码信号的非连续传输检测（dtx）的改进方法及装置 (Method and apparatus for discontinuous transmission Detection (DTX) of small block code signals ) 是由 骆亚铭 关文伟 刘向宇 贾康昊 曾江洲 于 2020-03-25 设计创作，主要内容包括：所描述的是一种用于在无线通信系统中处理上行链路控制信息(UCI)接收器处接收到的信号的方法和装置。该方法包括在UCI接收器处处理在上行链路(UL)上接收的信号,以将接收信号转换为可能的传输码字(θ-(1)…θi…θ-(N))的似然计算值。可能的传输码字(θ-(1)…θi…θ-(N))的似然计算值可以包括所述接收信号的多维离散傅里叶变换(DFT)(θ-(1)…θi…θ-(N))。多维DFT可以形成为哈达玛变换。该方法包括：从可能的传输码字(θ-(1)…θi…θ-(N))的所述似然计算值中确定最大幅度θ-(max)值,然后将θ-(max)值与选定的,计算的或预定的缩放阈值c.τ进行比较,其中τ是阈值,c是阈值τ的缩放因子。这使得在θ-(max)＞c.τ的情况下,在UCI接收器上确定UL上接收的信号包括线性分组码信号。在某些情况下,缩放因子c可以省略。(Described is a method and apparatus for processing a signal received at an Uplink Control Information (UCI) receiver in a wireless communication system. The method includes processing a signal received on an Uplink (UL) at a UCI receiver to convert the received signal into possible transmission codewords (θ) 1 …θi…θ N ) A likelihood calculation value of (c). Possible transmission code word (theta) 1 …θi…θ N ) Likelihood ofThe computed values may comprise a multi-dimensional Discrete Fourier Transform (DFT) (θ) of the received signal 1 …θi…θ N ). The multidimensional DFT may be formed as a hadamard transform. The method comprises the following steps: from the possible transmitted code words (theta) 1 …θi…θ N ) Determining a maximum amplitude θ of said likelihood calculations max Value of, then θ max The value is compared to a selected, calculated or predetermined scaling threshold c. This results in a change in θ max τ, determining at the UCI receiver that the signal received on the UL comprises a linear block code signal. In some cases, the scaling factor c may be omitted.)

1. A method of processing a signal received at an Uplink Control Information (UCI) receiver in a wireless communication system, the method comprising:

processing a signal received on an Uplink (UL) at the UCI receiver to convert the received signal into possible transmission codewords (θ)₁…θi…θ_N) Likelihood calculation values of (a);

according to possible transmission code word (theta)₁…θi…θ_N) Determining a maximum amplitude theta_maxA value; and

will the theta_maxThe value is compared with a selected, calculated or predetermined scaling threshold c.τ, where τ is the threshold value and c is a scaling factor of the threshold value τ, and the scaling threshold c.τ is obtained by multiplying the threshold value τ by the scaling factor c, at θ_maxIn the case > c.τ, the method includes determining, at the UCI receiver, that the signal received on the UL comprises a linear block code signal.

2. The method of claim 1, wherein θ is_maxIn the case of ≦ c.τ, the method includes outputting a Discontinuous Transmission (DTX) signal.

3. The method of claim 1, wherein the possible transmission codewords (Θ)₁…θi…θ_N) Comprises a multi-dimensional Discrete Fourier Transform (DFT) (theta) of the UL received signal at the UCI receiver₁…θi…θ_N) Said maximum amplitude θ_maxValues are derived from a plurality of real numbers including the multi-dimensional DFT.

4. The method of claim 3, wherein the multi-dimensional DFT (θ)₁…θi…θ_N) Comprising a Hadamard transform of a signal received on the UL at the UCI receiver.

5. The method of claim 1, wherein the threshold τ is derived from a target detection performance and a number of detections in a signal received on the UL at the UCI receiver.

6. The method of claim 5, wherein the target detection performance comprises any one of: a target probability (Pr (DTX → ACK)) of detecting DTX as an acknowledgement message (ACK); detecting DTX as a target probability (Pr (DTX → TX)) for Transmission (TX); or a target probability (pr (fa)) of detecting a false alarm in a signal received on the UL at the UCI receiver.

7. The method of claim 5, wherein the number of detections occurs is determined from a number of payload bits and/or a number of coded bits in a signal received on the UL at the UCI receiver.

8. The method of claim 5, wherein the threshold τ is derived from:

wherein

Wherein Q^-1(. cndot.) is the inverse of the Q function,

P_detect1-2Pr (DTX → ACK), or 1-Pr (DTX → TX), or 1-Pr (FA), and

N_bitis the number of payload bits and/or the number of coded bits in the signal received on the UL on the UCI receiver.

9. The method of claim 3, wherein the threshold τ is a mantissa probability (θ) according to the multi-dimensional DFT distribution₁…θi…θ_N) Is determined。

10. The method of claim 1, wherein determining, selecting, or calculating the scaling factor c comprises: a multi-dimensional DFT (θ) from signals received on the UL at the UCI receiver₁…θi…θ_N) The scaling factor c is estimated.

11. The method of claim 1, wherein determining, selecting, or calculating the scaling factor c comprises: calculating a multi-dimensional DFT (θ) of the signal received at the UL of the UCI receiver₁…θi…θ_N) The square root of the second order statistic of (c).

12. The method of claim 1, comprising the steps of:

according to the theta_maxValue generating UCI bits; and the number of the first and second groups,

when theta is_maxτ, and outputting an Acknowledgement (ACK) message or a Negative Acknowledgement (NACK) message based on the UCI bits.

13. The method of claim 1, wherein the scaling factor c ═ 1.

14. The method of claim 10, wherein the step of determining, selecting or calculating a scaling factor c is omitted such that the step of comparing comprises comparing the Θ to a threshold value_maxThe value is directly compared with the threshold τ so that at θ_maxIn the case of > τ, the method includes determining, at the UCI receiver, that the signal received at the UL comprises a linear block code signal.

15. The method of claim 10, wherein the step of determining, selecting or calculating a scaling factor c is omitted such that the step of comparing comprises comparing the Θ to a threshold value_maxThe value is directly compared with the threshold τ so that θ_maxτ, the method includes outputting a Discontinuous Transmission (DTX) signal.

16. The method of claim 14, comprising the steps of:

according to the theta_maxValue generating UCI bits; and the number of the first and second groups,

when theta is_max>τ outputting an Acknowledgement (ACK) message or a Negative Acknowledgement (NACK) message based on the UCI bits.

17. The method of claim 1, wherein the method is utilized to determine at the UCI receiver that the signal received on the UL comprises a small block code signal in a Long Term Evolution (LTE) communication system.

18. The method of claim 17, wherein the method is used to determine DTX in a small block coded signal comprising a new NR over air) Physical Uplink Control Channel (PUCCH) format, such as PUCCH format 2, PUCCH format 3 or PUCCH format 4.

19. The method of claim 1, wherein the linear block code comprises a Reed-Muller (RM) code or an RM-based supercode.

20. An Uplink Control Information (UCI) receiver in a wireless communication system, the receiver comprising:

a memory storing machine readable instructions; and

a processor for executing machine readable instructions such that when the processor executes the machine readable instructions it configures the receiver to:

processing a signal received on an Uplink (UL) at the UCI receiver to convert the received signal into possible transmission codewords (θ)₁…θi…θ_N) Likelihood calculation values of (a);

from the possible transmitted code words (theta)₁…θi…θ_N) Determining a maximum amplitude θ of said likelihood calculations_maxA value; and

will the theta_maxThe value is compared to a selected, calculated or predetermined scaling threshold c.τ, where τ is the threshold and c is the thresholdA scaling factor of the value τ, and the scaling threshold c.τ is obtained by multiplying the threshold τ by the scaling factor c, such that at θ_maxIn the case > c.τ, the method includes determining, at the UCI receiver, that the signal received on the UL comprises a linear block code signal.

21. A non-transitory computer readable medium storing machine readable instructions that, when executed by a processor, configure the processor to:

processing a signal received on an Uplink (UL) at the UCI receiver to convert the received signal into possible transmission codewords (θ)₁…θi…θ_N) Likelihood calculation values of (a);

from the possible transmitted code words (theta)₁…θi…θ_N) Determining a maximum amplitude θ of said likelihood calculations_maxA value; and

will the theta_maxThe value is compared to a selected, calculated or predetermined scaling threshold c.τ, where τ is the threshold value, c is a scaling factor of the threshold value τ, and the scaling threshold c.τ is derived by multiplying the threshold value τ by the scaling factor c such that at θ_maxIn the case of > c.τ, the method includes determining, at the UCI receiver, that the signal received on the UL comprises a linear block code signal.

Technical Field

The present invention relates particularly, but not exclusively, to an improved method and apparatus for determining a received signal on the Uplink (UL) at an Uplink Control Information (UCI) receiver in a wireless communication system, the received signal comprising a linear block code signal. The present invention also relates to a method and apparatus for improving detection of Discontinuous Transmission (DTX) on the UL at a UCI receiver, in particular for small block code signals.

Background

In the Downlink (DL) in a Long Term Evolution (LTE) communication system, data payloads are carried by transport blocks that are encoded into codewords that are transmitted over a Physical Downlink Shared Channel (PDSCH) referred to as a DL physical data channel. The scheduling information of the PDSCH codeword, including its resource allocation in the subframe and its modulation and coding scheme, is contained in a physical control channel called the Physical Downlink Control Channel (PDCCH). Typically, the receiving UE decodes the message in the PDCCH and, in case it is found that PDSCH has been allocated to it, it will decode the PDSCH codeword according to the scheduling information decoded from the PDCCH.

To prevent transport block loss, LTE has adopted a hybrid automatic repeat request (HARQ) scheme. In the physical layer of E-UTRA, HARQ is implemented in both UL and DL. The acknowledgement message in E-UTRA is denoted HARQ-ACK.

The UE may transmit HARQ-ACKs in response to certain PDSCH transmissions, and the HARQ-ACKs may include one or more acknowledgements (positive (ACK) or Negative (NACK)) in response to transport blocks transmitted in the DL. The HARQ-ACK may be sent on one of a physical channel Physical Uplink Control Channel (PUCCH) or PUSCH.

If the eNodeB (base station (BS)) detects an ACK instead of DTX (so-called ACK error detection), the eNodeB will erroneously assume that the corresponding DL transport block has been correctly received. Since the transport block has not been correctly received by the UE, the corresponding data will not be passed to the Medium Access Control (MAC) layer nor from the MAC layer to the Radio Link Control (RLC) layer. Therefore, data will be lost in the RLC layer. This will result in ARQ retransmissions in the RLC layer, which may introduce delays and possibly multiple retransmissions, which is highly undesirable. In addition, if a NACK is erroneously detected, which is actually a DTX, the eNodeB will retransmit the data packet in such a way that the UE cannot decode it.

As already noted, if the UE fails to decode the PDCCH successfully, a problem arises when the UE does not know the presence of the PDSCH allocated to it. In this case, the user equipment will not generate ACK/NACK information. This situation is well recognized and the UE response in this case is DTX, i.e. neither ACK nor NACK signal is sent to the eNodeB. Since the eNodeB does not have a priori knowledge about whether the UE fails to detect the PDCCH, it expects or considers the symbols of the predetermined location to be ACK/NACK symbols and extracts them for decoding by an ACK/NACK decoder. If the eNodeB ignores the possibility of DTX, the ACK/NACK decoder will return an ACK or NACK message to higher layers when decoding the extracted symbols, which do not actually convey any information. In general, both ACK and NACK messages may be returned as well.

The result of erroneously detecting DTX as ACK is more detrimental to system performance than erroneously detecting DTX as NACK.

Similarly, in 5G (or New Radio (NR)) wireless communication systems, message feedback schemes are also used for retransmission control. The ACK or nack (an) signal is used to indicate whether the UE successfully received the signal and whether the BS needs to retransmit the data. If the UE misses the DL control signal, the UE may encounter DTX in the DL and the UE will not send any message back to the BS. However, the BS needs to detect one of three possible feedback states, i.e., ACK, NACK or DTX, to reschedule the next transmission to the UE.

Fig. 1 shows a method by which UL payload control data from a UE to a BS and transmission of payload data on DL from the BS to the UE. In the example of fig. 1, it can be seen that in response to the first "DL control for payload allocation # 1" message from the BS to the UE, the UE responds with a UCI "NACK" message in this case. The NACK message is received by the UCI receiver at the BS, and therefore the BS is configured to retransmit the first "DL control for payload assignment # 1" message and its associated first "DL payload data # 1" message to the UE. In this example, the UE then returns a UCI "ACK" message to the UCI receiver in response to the retransmitted control signal message, and thus the BS is configured to subsequently send a second "DL control for payload allocation # 2" message and its associated second "DL payload data # 2" message to the UE (not shown in fig. 1). Thus, fig. 1 shows how the BS retransmits data to the UE when the UE indicates that the DL data control message has not been successfully received.

In contrast, fig. 2 shows a situation that may occur when the UE misses the DL data control message. In this example, the UE has missed the first "DL control for payload allocation # 1" message and, in response, has not sent an ACK/NACK message back to the BS. This scheme represents a DTX case. The UCI receiver at the BS only receives the noise but processes it as if it contained the UL UCI signal, with the result that, in this example, the UCI erroneously detects or determines that an ACK message was received from the UE, outputting an erroneous ACK message. This causes the BS to start new control and payload data transmission, e.g., "DL control for payload allocation # 2", etc., in response to the erroneous ACK message.

It is to be understood that in the example shown in fig. 2, where the UCI receiver does not have DTX detection or determination capability, the probability of the UCI receiver detecting an ACK message in error is 50%, the remaining 50% of the cases result in erroneous NACK messages. A false NACK message is less cumbersome than a false ACK message, but is still undesirable.

It is clear from the example of fig. 2 that there is room for improvement in detecting or determining ACK or NACK messages from a UE at a UCI receiver and distinguishing ACK/NACK messages from DTX conditions.

CN105262568 relates to ACK/NACK and DTX detection in a wireless communication system, wherein a DTX state threshold is calculated based on statistics of signal-to-noise ratio (SNR). However, obtaining accurate noise estimates can be challenging.

CN102740316 relates to a method for detecting an uplink DTX status. The method comprises the following steps: receiving data information from uplink user equipment of a current cell; calculating a confidence value corresponding to the data information, wherein the confidence value is used for reflecting the accuracy of decoding the data information carried by the receiving terminal; comparing the confidence value with a preset DTX judgment threshold value; and determining whether the uplink user equipment is in a DTX state according to the comparison result. Here, the preset DTX determination threshold must be changed for different channel conditions, and thus determining the DTX determination threshold requires a large amount of calculation work.

US8850285 relates to ACK/NACK/DTX detection in a wireless communication system and discloses a channel decoding block that receives a signal from a UE and generates a decoded ACK/NACK information vector.

US8315185 relates to ACK/NACK detection in LTE wireless communication systems. The ACK/NACK detector has a soft decoder and a decision maker. When the threshold is satisfied, the threshold is used to determine whether a signal transmitted from the UE contains an ACK/NACK transmission. If the threshold is not met, the transmission is determined to be DTX. The threshold is based on power estimates of the soft data bits.

For 5G UCI, 3GPP TS 38.212 needs to support two types of channel codes, namely polarization codes and small block codes, as shown in fig. 3 and 4, respectively. The polarization code is related to the case where the payload bits are larger than 11. The small block code is related to the case where the payload bits are equal to or less than 11.

As shown in fig. 3, in a conventional polar code-based receiver, a Cyclic Redundancy Check (CRC) may help detect whether DTX has occurred. The output of the polar decoder contains UCI bits, but the CRC check function (block) enables a polar-based receiver to distinguish between DTX and UCI bits, the latter indicating ACK or NACK, respectively.

A conventional receiver based on small block codes is shown in fig. 4, where the CRC function is not available, and incorrect detection of ACK, NACK or DTX signals results in a waste of resources for retransmission and/or loss of data packets. In a conventional small block code based receiver where CRC is not available, both ACK and NACK are sent out with a 50% probability, where the UE misses the DL control message and sends nothing to the UE, so that the BS receives only noise. In small block code based receivers, the output of the small block code decoder is assumed to be UCI bits, leading to possible false ACK or false NACK results. In other words, there is no way to distinguish DTX on the one hand and UCI bits indicating ACK or NACK on the other hand.

There is a need for a method for more accurately detecting Acknowledgement (ACK), Negative Acknowledgement (NACK) and Discontinuous Transmission (DTX) signals in a wireless communication system. There is also a need for a method of improving DTX detection on the UL at a UCI receiver and/or a method of determining a signal received on the UL, the signal comprising a linear block code signal, at a UCI receiver.

Disclosure of Invention

It is an object of the present invention to mitigate or eliminate one or more of the problems associated with known methods of determining signals received on the UL, including linear block code signals, at a UCI receiver to some extent.

The above object is achieved by the combination of the features of the main claim. The dependent claims disclose further preferred embodiments of the invention.

It is another object of the present invention to provide an improved method of detecting DTX on the UL at the UCI receiver, especially for small block coded signals.

It is another object of the present invention to provide an improved UCI receiver and/or UCI decoder.

Other objects of the present invention will be apparent to those skilled in the art from the following description. Accordingly, the foregoing description of the objects is not exhaustive, but is merely illustrative of some of the many objects of the invention.

The present invention relates to a method for processing a signal received at an Uplink Control Information (UCI) receiver in a wireless communication system. The method comprises processing a signal received on an Uplink (UL) at the UCI receiver to convert the received signal into possible transmission codewords (θ)₁…θi…θ_N) A likelihood calculation value of (c). The method comprises the following steps: from the possible transmitted code words (theta)₁…θi…θ_N) Determining a maximum amplitude θ of said likelihood calculations_maxValue of, then, the theta_maxThe value is compared to a selected, calculated or predetermined scaling threshold c. The comparison is such that at θ_maxτ, determining at the UCI receiver that the signal received on the UL comprises a linear block code signal. Preferably, at θ_maxUnder the condition that the value is less than or equal to c, the Discontinuous Transmission (DTX) signal is output.

In some cases, the scaling factor c may be omitted, such that the method then includes dividing the θ by the number of pixels_maxThe value is directly compared to the unscaled threshold τ, where for θ_max>τ, determining that the signal received on the UL comprises a linear block code signal. However, for θ_maxAnd tau is not more, a Discontinuous Transmission (DTX) signal is output.

Described is an apparatus for processing a signal received at an Uplink Control Information (UCI) receiver in a wireless communication system. The apparatus includes a receiver in a wireless communication system configured to process on an Uplink (UL) at the UCI receiverReceived signal to convert said received signal into possible transmission code words (theta)₁…θi…θ_N) A likelihood calculation value of (c). Possible transmission code word (theta)₁…θi…θ_N) May comprise a multi-dimensional Discrete Fourier Transform (DFT) (theta) of the received signal₁…θi…θ_N). The multi-dimensions may be formed as a hadamard transform. The UCI receiver is configured to receive a codeword (theta) from a possible transmission₁…θi…θ_N) Determining a maximum amplitude theta_maxValue of, then, the theta_maxThe value is compared to a selected, calculated or predetermined scaling threshold c.τ, where τ is the threshold and c is a scaling factor of the threshold τ, such that at θ_maxτ, determining at the UCI receiver that the signal received on the UL comprises a linear block code signal. In some cases, the scaling factor c may be omitted.

In a first broad aspect, the present invention provides a method of processing a signal received at an Uplink Control Information (UCI) receiver in a wireless communication system, the method comprising: processing an Uplink (UL) received signal at the UCI receiver to convert the received signal into possible transmission codewords (θ)₁…θi…θ_N) Likelihood calculation values of (a); according to possible transmission code word (theta)₁…θi…θ_N) Determining a maximum amplitude theta_maxA value; and will said theta_maxThe value is compared to a selected, calculated or predetermined scaling threshold c.τ, where c is a scaling factor of the threshold τ, and the scaled threshold c.τ is obtained by multiplying the threshold τ by the scaling factor c. Thus, at θ_maxIn the case > c.τ, the method includes determining, at the UCI receiver, that the signal received on the UL comprises a linear block code signal.

Preferably, at θ_maxIn the case of ≦ c.τ, the method includes outputting a Discontinuous Transmission (DTX) signal.

In one embodiment, the method comprises the steps of: based on the theta_maxThe sign and index of the value to generate UCI bits; and at theta_maxτ > cIn case, an Acknowledgement (ACK) message or a Negative Acknowledgement (NACK) message is output according to the UCI bit.

In another embodiment, the scaling factor c is omitted such that θ is scaled by_maxThe step of associating the value with the threshold τ comprises directly associating said θ with said value_maxThe value is compared to a threshold τ. For theta_max(> τ), the method includes determining, at the UCI receiver, that a signal received on the UL comprises a linear block code signal.

In this embodiment, at θ_maxIn case τ ≦ the method preferably includes outputting a Discontinuous Transmission (DTX) signal.

In this embodiment, preferably, the method comprises the steps of: based on the theta_maxThe sign and index of the value to generate UCI bits; and at theta_maxAnd if the bit is greater than the reference value tau, outputting an Acknowledgement (ACK) message or a Negative Acknowledgement (NACK) message according to the UCI bit.

In a second general aspect, the present invention provides an Uplink Control Information (UCI) receiver in a wireless communication system, the receiver comprising: a memory storing machine readable instructions; and a processor for executing the machine-readable instructions, such that when the processor executes the machine-readable instructions it configures the receiver to carry out the steps of the first main aspect of the invention.

In a third broad aspect, the invention provides a non-transitory computer readable medium storing machine readable instructions which, when executed by a processor, configure the processor to carry out the steps of the first broad aspect of the invention.

This summary does not necessarily disclose all features essential to the definition of the invention. The invention may reside in subcombinations of the disclosed features.

The foregoing has outlined rather broadly the features of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention.

Drawings

The foregoing and further features of the invention will become apparent from the following description of preferred embodiments, which is provided by way of example only, with reference to the accompanying drawings, in which:

fig. 1 is a signal diagram illustrating a message exchange between a BS and a UE for retransmitting control data and payload data;

fig. 2 is a signal diagram illustrating incorrect transmission of control data and payload data from a BS to a UE when a UCI receiver at the BS determines an erroneous ACK message;

FIG. 3 is a schematic block diagram of a conventional polar code based receiver for a 5G communication system;

FIG. 4 is a schematic block diagram of a conventional receiver based on small block codes for a 5G communication system;

fig. 5 is a schematic block diagram of a UCI receiver according to the present invention; and

fig. 6 is a diagram schematically illustrating the method steps according to the present invention performed by the UCI receiver of fig. 5.

Detailed Description

The following description describes preferred embodiments by way of example only and is not limited to the combination of features necessary to practice the invention.

Reference in the specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. In addition, various features are described which may be exhibited by some embodiments and not by others. Similarly, various requirements are described which may be requirements for some embodiments but not other embodiments.

It should be understood that the elements shown in the fig. may be implemented in various forms of hardware, software or combinations thereof. These elements may be implemented in a combination of hardware and software on one or more appropriately programmed general-purpose devices, which may include a processor, memory and input/output interfaces.

The present description illustrates the principles of the present invention. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described or shown herein, embody the principles of the invention and are included within its spirit and scope.

Moreover, all statements herein reciting principles, aspects, and embodiments of the invention, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Further, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future, i.e., any elements developed that perform the same function, regardless of structure.

Thus, for example, it will be appreciated by those skilled in the art that the block diagrams presented herein represent conceptual views of systems and apparatus embodying the principles of the invention.

The functions of the various elements shown in the figures may be provided through the use of dedicated hardware as well as hardware capable of executing software in association with appropriate software. When provided by a processor, the functions may be provided by a single dedicated processor, by a single shared processor, or by a plurality of individual processors, some of which may be shared. Moreover, explicit use of the term "processor" or "controller" should not be construed to refer exclusively to hardware capable of executing software, and may implicitly include, without limitation, digital signal processor ("DSP") hardware, read-only memory for storing software. ("ROM"), random access memory ("RAM"), and non-volatile memory.

In the claims hereof, any element expressed as a means for performing a specified function is intended to encompass any way of performing that function including, for example, a) a combination of circuit elements that performs that function or; b) any form of software, therefore, including firmware, microcode, etc., combined with appropriate circuitry for executing that software to perform the function. The invention as defined by such claims resides in the fact that: the functions provided by the various described means are combined together in the manner which is required by the claims. It is thus regarded that any means that can provide those functionalities are equivalent to those shown herein.

The present invention relates to a method for accurately detecting Acknowledgement (ACK), Negative Acknowledgement (NACK) and Discontinuous Transmission (DTX) signals in Uplink Control Information (UCI) in a wireless communication system. The invention is particularly suitable for DTX detection in receivers based on small block codes when the cyclic redundancy check, CRC, cannot be used for DTX detection.

Fig. 5 illustrates an exemplary embodiment of an improved UCI receiver apparatus 100 according to the inventive concept. In the illustrated embodiment, the UCI receiver apparatus 100 may include a communication device, such as a network node, network card or network circuit, or the like, communicatively connected to or forming part of the BS 105 (represented by dashed lines in fig. 5). Although the improved UCI receiver apparatus 100 of the present invention is not limited to operation in a 5G communication system, it may include a UCI receiver apparatus for a 4G cellular network or any cellular network.

The UCI receiver apparatus 100 may include a plurality of functional blocks for performing various functions thereof. For example, the UCI receiver apparatus 100 includes a receiver module 110 that provides received signal processing and is configured to provide received signals and/or information extracted therefrom to a function block module 120, which may include, for example, various data receivers, control elements, user interfaces, and the like. Although the receiver module 110 is described as providing receive signal processing, it should be understood that the functional blocks may be implemented as transceivers providing transmit and receive signal processing. Regardless of the particular configuration of the receiver 110, embodiments include a signal detection module 130 arranged in association with the receiver module 110 to facilitate accurate processing and/or decoding of received channel signals in accordance with the present invention. The channel signals may be received via the antenna module 105.

Although the signal detection module 130 is shown as being deployed as part of the receiver module 110 (e.g., including control and logic circuitry for a portion of the receiver module), there is no limitation on such a deployment configuration in accordance with the concepts of the present invention. For example, the signal detection module 130 may be deployed as a functional block of the UCI receiver apparatus 100 that is different from the receiver module 110, but is connected to the receiver module 110. The signal detection module 130 may be implemented, for example, using logic circuitry and/or executable code/machine readable instructions stored in the memory 140 of the UCI receiver apparatus 100 for execution by the processor 150 to perform the functions described herein. For example, executable code/machine-readable instructions may be stored in one or more memories 140 (e.g., Random Access Memory (RAM), Read Only Memory (ROM), flash memory, magnetic memory, optical memory, etc.), the one or more memories 140 being adapted to store one or more sets of instructions (e.g., application software, firmware, operating systems, applets, etc.), data (e.g., configuration parameters, operating parameters and/or thresholds, collected data, processed data and/or the like), and the like. The one or more memories 140 may include processor-readable memory for the one or more processors 150, which may be used to execute code segments of the signal detection module 130 and/or utilize provided data to perform the functions of the signal detection module 130 described herein. Additionally or alternatively, the signal detection module 130 may include one or more special-purpose processors (e.g., an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), a Graphics Processing Unit (GPU), and/or the like, configured to perform the functions of the signal detection module 130 described herein.

Fig. 6 schematically illustrates an improved receiver apparatus 100/200 based on linear block code (UCI), an improved decoder 210 for an improved receiver apparatus 100/200 based on linear block code (UCI), and an improved and enhanced method implemented by the signal detection module 130, including the improved decoder 210 for the receiver apparatus 100 based on UCI or the improved receiver apparatus 100/200 based on linear block code (UCI) of fig. 5.

As described in more detail below with respect to fig. 5 and 6, the signal detection module 130 including the improved decoder 210 is configured to accurately enable improved detection or determination of Acknowledgement (ACK), Negative Acknowledgement (NACK), and Discontinuous Transmission (DTX) signals in Uplink Control Information (UCI) in a wireless communication system.

In one embodiment, the UCI receiver device 100/200 is configuredIs arranged to receive the UL UCI signal as a demapper output signal. The demapper output signal is first equalized in a known manner in the equalizer module 202 to provide an equalized signal. The equalized signal is then demodulated and descrambled again in a known manner by a demodulation/descrambling module 204, which outputs soft bits to a modified decoder 210. In fig. 6, the improved decoder 210 is shown as a small block code decoder 210, but it is to be understood that this is shown by way of example only. The small block code decoder 210 is configured to process the received signal in a transformation module 210A to transform the received signal into likelihood computed values of possible transmitted codewords in the received signal in step 300. Preferably, the computed values of likelihood of possible transmitted codewords comprise a multi-dimensional Discrete Fourier Transform (DFT) (θ) of the received signal₁…θi…θ_N). At UCI receiver means 100/200, a UL UCI signal is received from a UE 125 operating in a 5G communication system environment 115, the UE 125 wirelessly connecting to the BS 105 via a UL channel. However, it is to be understood that the signal received at the UCI receiving means 100/200 may contain noise in only one instance, in which the UE 125 missed the DL control message from the BS 105, and therefore the UE 125 did not issue any message or signal in response to the missed DL control message. In this case, the UCI receiver means 100/200 expects to receive a reply message from the UE 125, and therefore treats the received noise as a UL UCI signal to be processed. In either case, whether a true UL UCI signal from the UE 125 or a noise signal mistaken for a true UL UCI signal from the UE 125, the small block code decoder 210 processes the "received signal" to transform the signal into a multi-dimensional Discrete Fourier Transform (DFT) (θ) that is a multi-dimensional Discrete Fourier Transform (DFT) (i.e., a single-bit code decoder)₁…θi…θ_N)。

As noted above, the signal detection module 130 of fig. 5 may include a modified decoder 210 for the linear block code (UCI) based modified receiver apparatus 100/200 of fig. 6, in one embodiment the polar code decoder forming part of the polar code based conventional receiver of fig. 3 is replaced with the modified decoder 210, or more preferably, in another embodiment, the modified decoder 210 replaces the small block code decoder forming part of the small block code based conventional receiver of fig. 4, as shown in fig. 6.

It will be understood from the description that although the improved decoder 210 of the present invention may be implemented by implementing only software changes, the signal detection module 130 including the improved decoder 210 may be implemented by changes to software, firmware and/or hardware of a conventional linear block code decoder.

The likelihood calculation values for possible transmitted codewords in the UL UCI signal received at the UCI receiver means 100/200 may be represented as likelihood values. Multidimensional DFT (θ)₁…θi…θ_N) A hadamard transform (hadamard) of the received signal may be included. The Hadamard transform is also called a Hadamard-Hadamard transform, Hadamard-radmach-warfare transform, Hadamard-Rademacher-Walsh transform, warburg transform or Walsh-Fourier transform. It will be referred to herein as a "hadamard transform" but encompasses all forms of the transform.

The module 210B of the small block code decoder 210 is configured to determine the maximum amplitude θ in step 305 from the likelihood calculation values of the possible transmitted codewords_maxThe value is obtained. Maximum amplitude theta_maxValues may be derived from including the multidimensional DFT (θ)₁…θi…θ_N) A plurality of real number determinations or calculations.

In the conventional UCI receiver, as shown in fig. 3 and 4, UCI bits indicating ACK or NACK messages are from the maximum amplitude θ_maxThe index and sign of the value. Similarly, the UCI bit module 210C of the small block code decoder 210 is configured to depend on the maximum amplitude θ in a known manner in step 310_maxThe index of the value and the sign generate UCI bits.

As already described with respect to fig. 4, there is no CRC function in a conventional receiver based on small block codes, which prevents determining whether a received UL UCI signal actually indicates a DTX condition rather than an ACK or NACK message. In other words, the lack of a CRC function prevents the determination between DTX and ACK/NACK.

Will the theta_maxThe value is compared to a selected, calculated or predetermined scaling threshold c.τ, where c is a scaling factor of the threshold τ, and the scaling threshold c.τ is obtained by multiplying the threshold τ by the scaling factor c. I.e. at theta_maxIn the case > c.τ, the method includes determining, at the UCI receiver, that the signal received on the UL comprises a linear block code signal.

The first embodiment of the method of the present invention, denoted as (ii) in FIG. 6, includes, in step 315, applying the theta_maxA step of comparing the value with a selected, calculated or predetermined scaling threshold value c.τ, where c is a scaling factor for the threshold value τ, the threshold value τ and said scaled threshold value c.τ being obtained by multiplying the threshold value τ by the scaling factor c. The determined, selected or calculated scaling factor c may be passed by the DTX detector for the UCI module 210D from the multi-dimensional DFT (θ)₁…θi…θ_N) Obtained by estimating the scaling factor c, but preferably by computing the second order statistic (θ) of the multidimensional DFT₁…θi…θ_N) Is obtained as the square root of:

the scaling factor c is directly based on the calculated likelihood of a possible transmitted codeword and thus has low computational complexity and stable performance since it does not depend on obtaining a signal noise estimate.

The DTX detector for the UCI module 210D for the small block code decoder 210 has loaded a predetermined threshold τ into its memory. Preferably, the threshold τ is derived from the target detection performance and the number of occurrences in the signal received on the UL detected by said UCI receiver means 100/200. The target detection performance may include any one of: a target probability (Pr (DTX → ACK)) of detecting DTX as an acknowledgement message (ACK); detecting DTX as a target probability (Pr (DTX → TX)) of transmitting the message (TX); or a target probability of detecting a false alarm (pr (fa)) in a signal received on the UL at the UCI receiver device 100/200. Preferably, the number of detections occurring is determined from the number of payload bits and/or the number of coded bits in the signal received on the UL on said UCI receiver means 100/200.

alarm(Pr(FA))in the signal received on the UL at said UCI receiver device 100/200.The

20 number of detection occurrences is preferably determined from a number or payload bits and/or a number of encoded bits in the signal received on the UL at said UCI receiver device 100/200.

The threshold τ may also be determined according to a tail probability of the distribution of the multi-dimensional DFT (θ₁....θ_i....θ_N).

25 More particularly.the threshold τis derived from：

where

The threshold τ may also be based on the mantissa probability (θ) of the distribution of the multidimensional DFT₁....θ_i....θ_N) To be determined.

More specifically, the threshold τ is derived from the following equation:

wherein the content of the first and second substances,

wherein Q^-1(. cndot.) is the inverse of the Q function,

P_detect1-2Pr (DTX → ACK), or 1-Pr (DTX → TX), or 1-Pr (FA), and

N_bitis the number of payload bits and/or the number of coded bits in the signal received on the UL at the UCI receiver means 100/200.

For clarity, only P is shown in FIG. 6_detect＝1-2Pr(DTX→ACK)。

The threshold τ depends on the two inputs, i.e. the target probability and the number of payload bits and/or the number of coded bits as described above. Thus, the threshold τ may be predetermined and loaded into the memory 140 of the UCI receiver device 100/200. Thus, the threshold τ need not necessarily be determined in real time. Furthermore, the scaling threshold c.τ is adapted to different channels or channel conditions, which greatly simplifies the method of the present invention and reduces the computational effort in the signal detection module 130/small block code decoder 210.

In step 315, the small block code decoder 210 is configured to: when theta is_maxτ, it is determined whether the signals received by the UCI receiver means 100/200 on the UL comprise linear block code signals. However, at θ_maxIn the case of ≦ c.τ, a Discontinuous Transmission (DTX) signal is output in step 315.

At theta_max>c. τ, step 315 may be enhanced to output an Acknowledgement (ACK) message or a Negative Acknowledgement (NACK) message based on the generated UCI bits.

Thus, it can be seen, although not exclusively, that the method of this embodiment may be most usefully employed in small block code based receivers without CRC functionality, such as illustrated in fig. 4, to determine whether the signals received on the UL at UCI receiver apparatus 100/200 comprise linear block code signals, and also to detect or determine the received signals, whether real or noisy signals, including ACK messages from UEs 125 or NACK messages from UEs 125. In other words, the method of the first embodiment may not only determine whether the received signal comprises a linear block code signal, but also enable the improved decoder 210 to distinguish between DTX cases on the one hand and ACK/NACK signals on the other hand. The method of the first embodiment is therefore particularly useful in a wireless communication system for DTX detection in a small block code based receiver, where cyclic redundancy check, CRC, cannot be utilized for DTX detection.

Thus, the method may be used to determine at UCI receiver apparatus 100/200 that a signal received on the UL comprises a small block code signal in a Long Term Evolution (LTE) communication system, and more particularly, may be used to determine that an NR (5G) Physical Uplink Control Channel (PUCCH) format, such as PUCCH format 2, PUCCH format 3 or PUCCH format 4, is included in the small block code signal.

It will be appreciated that the linear block code may be a Reed-Muller (RM) code or an RM based supercode.

Typically, the signal power will vary over time. For example, in the case of DTX, the received signal contains only noise, and the noise power is not constant over time. Therefore, it is necessary to estimate the noise power at one or more points in time (e.g., based on all (θ))₁…θi…θ_N)). Otherwise, due to (θ)₁…θi…θ_N) Is large, not due to the presence of (theta)₁…θi…θ_N) Middle theta_maxIndeed, the maximum amplitude θ derived from the received signal including only noise_maxThe value may still be such that the maximum amplitude θ_maxThe value is greater than the threshold τ. Using the scaling factor c with the threshold τ helps to solve this problem.

On the other hand, the scaling factor c may be omitted in case e.g. we have a priori knowledge of the long-term noise power. In this case, it may be determined that the noise on the UL channel does not change rapidly with time, or it may be determined that it follows a certain distribution. In this way, the noise power can be considered as a constant or at least a known entity. Thus, it is no longer necessary to apply a scaling factor to the threshold τ as long as a suitable level is selected for the threshold τ.

Referring again to fig. 5 and 6, in another embodiment of the method of the present invention, indicated by (i) in fig. 6, the step of selecting, calculating or determining the scaling factor is omitted. In the enhancement method (i) of fig. 6, the method comprises a step 310 of the signal detection module 130, which comprises modifying the decoder 210 in a known manner according to the maximum amplitude θ_maxThe index of the value and the sign generate UCI bits. The enhancement method further includes an enhancement step 315 of enhancing the theta_maxThe value is directly compared to the threshold τ.

For theta_max(> τ), the method includes determining, at the UCI receiver apparatus 100/200, that the signal received on the UL comprises a linear block code signal.

In the enhancement step 315, the small block code decoder 210 is configured to: when theta is_max(> τ), it is determined at the UCI receiver apparatus 100 that the signal received on the UL comprises a linear block code signal. However, at θ_maxIn the case of ≦ τ, a Discontinuous Transmission (DTX) signal is output at the enhancement step 315.

At theta_max(> τ), the enhancing step 315 may output an Acknowledgement (ACK) message or a Negative Acknowledgement (NACK) message based on the generated UCI bits.

The present invention provides a UCI receiver apparatus 100 for a wireless communication system. The UCI receiver device 100 includes a memory 140 storing machine-readable instructions and a processor 150 for executing the machine-readable instructions, such that when the processor 150 executes the machine-readable instructions, it configures the UCI receiver device 100 to implement the aforementioned methods (i) and (ii) according to the present invention.

The present invention provides a non-transitory computer readable medium 140 storing machine readable instructions which, when executed by a processor 150, configure the processor 150 to implement the aforementioned methods (i) and (ii) according to the present invention.

The above means may be implemented at least partly in software. Those skilled in the art will appreciate that the above-described apparatus may be implemented, at least in part, using general purpose computer equipment or using custom equipment.

Here, aspects of the methods and apparatus described herein may be performed on any apparatus including a communication system. The procedural aspects of the technology may be viewed as an "article of manufacture" or an "article of manufacture" typically in the form of executable code and/or executable code embodied on some type of machine-readable medium and/or associated data. "storage" type media include any or all of the memory of a mobile station, computer, processor, etc., or associated modules thereof, such as various semiconductor memories, tape drives, disk drives, etc., that may provide storage for software programming at any time. All or portions of the software may sometimes communicate via the Internet or other various telecommunications networks. For example, such communication may enable loading of software from one computer or processor into another computer or processor. Thus, another type of media which may carry software elements includes optical, electrical, and electromagnetic waves, such as those used in physical interfaces between local devices over wired and optical landline networks and over various wireless links. Physical elements carrying such waves, such as wired or wireless links, optical links, etc., may also be considered as media carrying software. As used herein, unless limited to a tangible, non-transitory "storage" medium, terms such as a computer or machine "readable medium" refer to any medium that participates in providing instructions to a processor for execution.

While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only illustrative embodiments have been shown and described and that the scope of the invention is not limited in any way. It is to be understood that any feature described herein may be used with any embodiment. The illustrative embodiments are not mutually exclusive or exclude other embodiments not enumerated herein. Accordingly, the present invention also provides embodiments that include combinations of one or more of the illustrative embodiments described above. Modifications and variations may be made to the present invention without departing from its spirit and scope, and, accordingly, such limitations should be imposed as are indicated by the appended claims.

In the appended claims and the previous description of the invention, the word "comprise" or variations such as "comprises" or "comprising" are used in an inclusive sense, unless the context requires otherwise due to express language or necessary implication. I.e. specifying the presence of the stated features but not excluding the presence or addition of other features, in various embodiments of the invention.

It will be appreciated that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms part of the common general knowledge in the art.