A method and apparatus for signal processing in a communication system

[0050] Hereinafter, the principle and spirit of the present disclosure will be described with reference to illustrative embodiments. It should be understood that all these embodiments are given only for the purpose of a person skilled in the art to better understand and further practice the present disclosure, and not for the purpose of limiting the scope of the present disclosure.

[0051] References to "one embodiment", "exemplary embodiment", etc. in the present disclosure indicate that the described embodiment may include specific features, structures, or characteristics, but it is not necessarily required that each embodiment includes the specific features , Structure, or characteristics. Furthermore, such phrases are not necessarily referring to the same embodiment.

[0052] It should be understood that although the terms "first" and "second" and so on may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

[0053] The terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the exemplary embodiments. It should be understood that the words "including" and/or "having" when used in the present disclosure indicate the existence of the stated features, elements, and/or components, etc., but do not exclude one or more other features, elements, The presence or addition of components and/or combinations thereof.

[0054] In the following specific embodiments and claims, unless otherwise defined, all technical and scientific terms used in this disclosure have the same meaning as generally understood by those of ordinary skill in the field to which this disclosure belongs.

[0055] In the existing long-term evolution-based narrowband IoT, for example, in the downlink from the base station to the terminal, all carriers are combined before frequency processing, resulting in the narrowband IoT time-domain signal and long-term evolution. Mixing of domain signals. Although this method can ensure that the signals have common frequency characteristics after subsequent frequency processing, for example, have a fixed peak-to-average power ratio, it obviously cannot meet the needs of narrowband IoT signals in some use cases to have their own unique frequencies. Feature requirements. Therefore, the present disclosure proposes the following methods, devices, and computer program products described in conjunction with the drawings to solve the above problems.

[0056] figure 1 It is a flowchart schematically illustrating a method 100 according to an embodiment of the present disclosure.

[0057] The method 100 may include dividing the input signal into a first part and a second part (block 110). In an exemplary embodiment according to the present disclosure, dividing the signal may include dividing the signal in the time domain and/or dividing the signal in the frequency domain. Those skilled in the art should understand that dividing the signal may also include dividing the signal in any aspect. For example, the signal may be divided according to the peak frequency of the signal, according to the appearance time of the signal, according to the number of frequency components contained in the signal, and so on. Any suitable existing and/or software and/or hardware technology that will be developed in the future can be used to divide the signal, for example, a frequency divider, multiplexer, etc. are used to divide the signal.

[0058] In addition, in the embodiments according to the present disclosure, the signal can also be divided into more than two parts according to actual needs.

[0059] After obtaining the first part and the second part through the above-mentioned division, the method 100 may further include performing crest factor reduction processing on the first part (block 120). Those skilled in the art should understand that other signal processing can be performed on the first part as needed. Those skilled in the art should also understand that any suitable existing and/or future software and/or hardware technology to be developed can be used to perform the crest factor reduction processing.

[0060] The purpose of performing crest factor reduction processing is to limit the peak-to-average power ratio of the signal. Because the peak-to-average power ratio of the signal is too large, for example, the amplitude of the superimposed signal of the sub-carrier exceeds the dynamic range of the power amplifier, which will cause signal distortion, signal distortion, increase in noise power in the frequency band, and out-of-band power diffusion. Therefore, when the signal is superimposed, the peak-to-average power ratio of the signal needs to be limited to ensure that the signal is not distorted.

[0061] The most direct method for performing the crest factor reduction processing can be to perform peak clipping processing on the signal with a selected threshold, that is, to remove the amplitude peak value of the signal, so as to obtain a signal that meets the dynamic range of the power amplifier. In an exemplary embodiment, the crest factor reduction process may further include a peak clipping process and an average power loss compensation process, wherein the average power loss compensation process functions to achieve a constant output power after the crest factor reduction process is performed.

[0062] However, as mentioned above, the crest factor reduction process will inevitably introduce noise into the processed signal. If some frequency processing is continued on the processed signal, for example, the power spectral density of the processed signal is increased, the noise introduced will also be increased when the power spectral density of the signal is increased. If the processed signal includes two or more different parts, the noise of the two or more different parts will be increased equally, which may be unacceptable for the subsequent signal processing, especially when required The two or more different parts have different frequency properties.

[0063] Therefore, after the method 100 divides the input signal into two parts in block 110, the crest factor reduction process can be performed only on the first part in block 120, and the crest factor reduction process is not performed on the second part. The noise generated by the crest factor reduction processing performed on the first part will not be introduced into the second part. In this case, the method 100 may perform frequency processing on the first part that has undergone crest factor reduction and the second part that has not been processed by crest factor reduction (block 130), thereby separately considering and satisfying their different frequency requirements. . For example, how much peak-to-average power ratio they need and/or how much noise they may be able to tolerate, etc. This way of performing separate frequency processing on different parts can obviously better take into account the frequency requirements of different signals in different usage scenarios.

[0064] After the two parts of the signal are subjected to separate frequency processing, the method 100 may include combining the frequency-processed first part and the second part (block 140) for subsequent processing. Although the two parts are combined again, they still have their own required frequency characteristics. Those skilled in the art should understand that any suitable existing and/or future software and/or hardware technologies to be developed can be used to perform the combination.

[0065] In an exemplary embodiment, the method 100 may further include adjusting the delay of the second part before combining the frequency-processed first part and the second part. Because the first part has undergone crest factor reduction processing and the second part has not undergone crest factor reduction processing, the two signal parts obtained after processing may not be aligned in time. Therefore, in order to combine the two parts, it may be necessary to adjust the time delay of the second part without crest factor reduction processing to align the two parts in time, thereby facilitating the subsequent processing of the combined signal. In an exemplary embodiment, the method 100 may also perform delay adjustment on both the frequency-processed first part and/or the second part. Those skilled in the art should understand that any suitable existing and/or future software and/or hardware technology can be used to adjust the delay to achieve the purpose of alignment of the two-part signal.

[0066] In an exemplary embodiment, in the method 100, performing frequency processing on the first part subjected to the crest factor reduction process and the second part not subjected to the crest factor reduction process in block 120 may include performing frequency processing on the crest factor reduction process. The processed first part and the second part not processed by crest factor reduction are respectively processed for power spectral density, so that the power spectral density of the second part not processed by crest factor reduction is greater than the power of the first part processed by crest factor reduction Spectral density. Those skilled in the art should understand that the frequency processing may include any suitable other frequency processing.

[0067] If the initial signal is a downlink signal, after the above-mentioned power spectral density processing, the second part with greater power spectral density will have a downlink coverage greater than that of the first part and will not be processed by crest factor reduction. Has less noise than the first part. In this case, because the terminal will receive a better downlink reference signal due to the greater power spectral density of the second part of the downlink, the frequency error, timing error, etc. of the uplink number will also Correspondingly decrease, which leads to a corresponding increase in uplink coverage. This allows the two parts of the signal to have different coverage areas, so that the base station and/or network element that transmits the downlink signal can be deployed more flexibly, and thus for some base stations and/or network elements in the wireless communication system. Network elements undoubtedly have considerable benefits.

[0068] In an exemplary embodiment, the crest factor reduction processing performed in block 120 may include peak clipping processing and average power loss compensation processing. As described above, in order to adapt the amplitude of the signal to the dynamic range of the power amplifier to reduce a series of disregarding effects such as distortion, it is necessary to perform crest factor reduction processing on the signal. The peak clipping process in the crest factor reduction process can remove the peak value of the signal to obtain a signal amplitude suitable for the power amplifier. However, the received signal after the peak clipping process may not be ideal for subsequent processing. Therefore, the crest factor reduction process may further include an average power loss compensation process to compensate for the average power loss due to the peak clipping process. After the crest factor reduction processing, a constant output power is realized, which is beneficial to the subsequent processing of the signal. In another exemplary embodiment, the crest factor reduction processing performed in block 120 may also include only peak clipping processing. Those skilled in the art should understand that any suitable existing and/or future software and/or hardware technology to be developed can be used to perform the crest factor reduction processing.

[0069] In an exemplary embodiment, the method 100 may be applied to the field of narrowband Internet of Things to solve the technical problems mentioned in the background art section. According to the existing specifications of 3GPP, as mentioned above, the NB-IoT can be deployed in the long-term evolution system in three ways. Those skilled in the art should understand that the NB-IoT can also be deployed in the long-term evolution system in any other suitable manner. Those skilled in the art should understand that the narrowband Internet of Things can also be similarly deployed in future communication systems, for example, deployed in a fifth-generation (5G)/New Radio (NR) system.

[0070] Therefore, in an exemplary embodiment, the second part obtained by dividing the signal in block 110 may be a narrowband IoT signal. That is, the narrowband IoT signal can be extracted from the mixed signal or provided in a separate manner to provide the narrowband IoT signal, for example, the narrowband IoT signal can be passed through a separate channel for possible separate processing.

[0071] In another exemplary embodiment, the first part obtained by dividing the signal in block 110 may be a long-term evolution signal or a new radio signal. Similarly, the long-term evolution signal or the new radio signal can be extracted from the mixed signal or provided in a separate manner to provide the long-term evolution signal or the new radio signal, for example, the long-term evolution signal or the new radio signal can be passed through a separate channel to Carry out possible separate treatment. In an exemplary embodiment, if the narrowband Internet of Things is deployed in a long-term evolution and/or new radio system in some way, according to the method 100 of the present disclosure, the narrowband Internet of Things signal can be combined with the long-term evolution signal or the new radio signal. Separate.

[0072] In an exemplary embodiment, the narrowband IoT signal may be a narrowband IoT time domain signal and the long-term evolution signal or new radio signal may be a long-term evolution time domain signal or a new radio time domain signal. Because in a communication system, the transmitted signal is usually a time domain signal. The time domain signal is usually mixed with different signals to use the same components for processing and transmission, thereby reducing the number of components on the transmitting end. Therefore, the time domain signal may be a mixed signal that mixes different systems, different functions, different signal specifics, etc., but in most cases, the different signals that constitute the mixed signal need to have their own characteristics to satisfy the system and/or the Functional requirements, therefore, the method 100 according to the present disclosure is required to meet the different individual requirements of these different signals in the mixed signal.

[0073] In an exemplary embodiment, the above-mentioned narrowband IoT time domain signal may be obtained through conversion of a narrowband IoT frequency domain signal corresponding to the narrowband IoT signal, a long-term evolution time domain signal or a new radio time domain signal It may be obtained through conversion of a long-term evolution frequency domain signal or a new radio frequency domain signal corresponding to a long-term evolution signal or a new radio signal. In the communication system, the frequency domain signal can be converted to obtain the time domain signal. The conversion may include various suitable frequency-time conversions, such as inverse fast Fourier transform (IFFT). Those skilled in the art should understand that any suitable existing and/or future software and/or hardware technology to be developed can be used to perform the conversion. Those skilled in the art should understand that the above-mentioned time-domain signal and frequency-domain signal may be any time-domain signal and frequency-domain signal suitable for wireless and/or wired communication systems.

[0074] In an exemplary embodiment, the above-mentioned narrowband IoT frequency domain signal may be deployed in the long-term evolution frequency domain signal or the new radio frequency domain signal in an in-band manner, or the narrowband IoT signal may be protected The frequency band approach is deployed in the long-term evolution frequency domain signal or the new radio frequency domain signal. Those skilled in the art should understand that the above-mentioned signals can be deployed in any other suitable manner.

[0075] In other words, the method 100 can be applied to the guard band deployment mode and in-band deployment mode of the narrowband Internet of Things as described above. Among them, the guard band deployment method refers to that the frequency band allocated to the narrowband Internet of Things is located in the guard band between the long-term evolution or new radio operating frequency bands. In-band deployment means that the frequency band allocated to the narrowband Internet of Things is within the long-term evolution or new radio operating frequency band. That is, long-term evolution or new radio networks will reserve certain frequency bands for the deployment of narrowband IoT.

[0076] As mentioned above, in the field of narrowband IoT, guard band deployment and in-band deployment will cause the time domain signals of narrowband IoT to be mixed with long-term evolution or new radio time domain signals when transforming from frequency domain to time domain. In turn, the narrowband IoT signal cannot have a higher power spectral density gain due to the long-term evolution or the limitation of the new radio signal in terms of peak-to-average power ratio and/or noise tolerance. Therefore, in some existing use cases of narrowband IoT, if it is desired to increase the power spectral density of the narrowband IoT time domain signal to 10dB or higher, the long-term evolution or new radio time domain signal mixed with it will suffer The interference of large noise that increases as the power spectral density increases and therefore will affect the throughput. In this case, the method 100 can be used to make the narrowband IoT signal have different characteristics from the long-term evolution or new radio signal in some aspects to meet certain application scenarios. For example, the method 100 according to the present disclosure can be applied to individually increase the power spectral density of the narrowband IoT time domain signal without greatly increasing the noise of the long-term evolution or new radio time domain signal.

[0077] Those skilled in the art should understand that the method 100 described according to the above-mentioned embodiments of the present disclosure is also applicable to other broadband signals including narrowband signals similarly deployed in-band or guard band deployment.

[0078] Reference now figure 2 , figure 2 It is a block diagram schematically illustrating an apparatus 200 for signal processing in a communication system according to an embodiment of the present disclosure. The device 200 may include a processor 210 and a memory 220. In various embodiments, the processor 210 and the memory 220 may be implemented in various ways. As an example, the processor 210 may be implemented as one or more microprocessors or microcontrollers, application specific integrated circuits, digital signal processors, dedicated digital logic, and the like. In various embodiments, the memory 220 may be implemented in various ways. As an example, the memory 220 may be implemented as one or several types of memory, such as read-only memory, random access memory, cache memory, flash memory device, optical storage device, and so on. The memory 220 may be communicatively coupled to the processor 210 and is adapted to store when executed by the processor 201 so that the device 200 executes figure 1 Instructions describing the operation of the method.

[0079] image 3 It is a block diagram schematically illustrating a device 300 for signal processing in a communication system according to an embodiment of the present disclosure. In one embodiment, the device 300 may include a dividing component 310, a crest factor reduction component 320, a frequency processing component 330, and a combining component 340. Those skilled in the art should understand that image 3 The device 300 shown may also include or be implemented with other components. Such as image 3 As shown, the dividing part 310 is operable to divide the input signal into a first part and a second part. The crest factor reduction unit 320 is operable to perform crest factor reduction processing on the first part. The frequency processing part 330 is operable to perform frequency processing on the first part subjected to the crest factor reduction processing and the second part not subjected to the crest factor reduction processing respectively; and the combining part 340 is operable to combine the frequency processed parts The first part and the second part.

[0080] Although parts 310-340 are in image 3 Are shown as separate components, but those skilled in the art should understand that they can be combined in any manner. And these components and their combination can be implemented by any suitable existing and/or future developed software, hardware and/or firmware.

[0081] Those skilled in the art should understand that the device 300 shown can be implemented with any suitable existing and/or future-developed software, hardware, and/or firmware for performing related figure 1 Described method.

[0082] Figure 4 Is a block diagram schematically illustrating a circuit 400 according to an embodiment of the present disclosure. Such as Figure 4 As shown, in one embodiment, the circuit 400 may include two independent time-domain signal processing channels. The first channel may include a narrowband IoT baseband modulator 410, a frequency processing part 420, and a delay adjustment part 430 connected in series. The second channel may include a long-term evolution or new radio time-domain signal baseband modulator 440, a crest factor reduction processing part 450, and a frequency processing part 460 connected in series. The circuit 400 also includes a combining part 470 for combining the output signals of the two channels. The output of the combining component 470 may be provided to a subsequent power amplifier 480 to be finally used for transmission via the antenna 490. Those skilled in the art should understand that the circuit 400 is only exemplary and therefore the circuit 400 may also include any other circuit components required for signal processing of the communication system.

[0083] Such as Figure 4 As shown, in one embodiment, the narrowband IoT time domain signal and the long-term evolution or new radio time domain signal may be input to the corresponding baseband modulators 410 and 440 through the first channel and the second channel, respectively. That is, the time domain signal obtained by converting the frequency domain signal corresponding to the narrowband IoT signal and the long-term evolution or new radio signal, including the narrowband IoT time-domain signal and the long-term evolution or new radio time-domain signal, can be processed before the input channel. Divided into two independent parts (not shown). In the first channel, after being modulated by the baseband modulator 410, the narrowband IoT time domain signal can be input to the frequency processing part 420 for frequency processing. The signal processed by the frequency domain processing part 420 may be output to the delay adjustment part 430 to perform delay adjustment as needed to perform time alignment with the signal output by the second channel. In the second channel, the long-term evolution or new radio time-domain signal may be input to the crest factor reduction processing part 450 after being modulated by the baseband modulator 440 for crest factor reduction processing. The crest factor reduction processing unit 450 is operable to perform two operations, namely, peak clipping processing and average power loss compensation processing. The signal processed by the crest factor reduction part 450 may be output to the frequency processing part 460 for frequency processing. The signal processed by the frequency processing part 460 may be output to the combining part 470 to be combined with the signal output by the first channel. The output of the combining component 470 may be provided to a subsequent power amplifier 480 for final use in transmission via the antenna 490.

[0084] From Figure 4 And above Figure 4 It can be seen from the description that the frequency processing components 420 and 460 can respectively perform frequency domain processing on the narrowband IoT time domain signal and the long-term evolution or new radio time domain signal, for example, making the power spectral density of the narrowband IoT time domain signal greater than the long-term evolution Or the power spectral density of the new radio time domain signal. Since only the long-term evolution or new radio time domain signals have undergone the crest factor reduction processing of the crest factor reduction processing unit 450 that introduces noise, the narrowband IoT time domain signals that have not been processed by the crest factor reduction processing unit in the first channel will not Suffer from the noise effect caused by the increased crest factor reduction process due to the substantial increase in power spectral density. Correspondingly, since the power spectral density of the long-term evolution or new radio time-domain signal in the second channel has not been greatly increased, the long-term evolution or new radio time-domain signal will not suffer from the peak caused by the large increase in power spectral density. A large increase in noise caused by factor reduction processing. Therefore, the circuit 400 according to the embodiment of the present disclosure can well meet the different frequency requirements of different signals.

[0085] The reason why the narrowband IoT time-domain signal can be processed without crest factor reduction without signal distortion is because the QPSK modulation mode can be used to modulate the narrowband IoT signal and occupy only a very limited subcarrier, thus making the narrowband IoT The peak-to-average power ratio of time-domain signals is less than that of long-term evolution or new radio time-domain signals. In addition, the narrowband IoT signal can tolerate higher noise caused by peak clipping due to its QPSK modulation mode. This will further improve the performance of the entire communication system.

[0086] Figure 5 It is a block diagram schematically illustrating the signal processing in the baseband part and the radio frequency part according to an embodiment of the present disclosure. Figure 5 The implementation of the method according to the embodiments of the present disclosure in the baseband part and the radio frequency part is shown from a signal perspective.

[0087] reference Figure 5 In an exemplary embodiment, the frequency domain symbols corresponding to the carrier may be generated in the baseband part. The frequency domain symbols include long-term evolution or new radio frequency domain symbols and narrowband IoT frequency band symbols. in Figure 5 In, the long-term evolution or new radio frequency domain symbols are shown in blank boxes, and the narrow-band IoT frequency band symbols are shown in black solid boxes. After these frequency domain symbols are mapped to resource elements, they can be converted into time domain signals and can be divided into two different parts. The conversion may include performing an inverse fast Fourier transform and adding a cyclic prefix. Those skilled in the art should understand that the conversion may include any suitable various conversion algorithms for frequency domain to time domain conversion. The converted time-domain signal can be divided into the narrowband IoT time-domain signal on the left and the long-term evolution or new radio time-domain signal on the right, and then they enter the radio frequency part for further processing.

[0088] In an exemplary embodiment, in the radio frequency part, the narrowband IoT time-domain signal on the left side may undergo frequency processing and delay adjustment and then output to be combined with the processed long-term evolution or new radio time-domain signal on the right side . In an exemplary embodiment, the frequency domain processing may be, for example, increasing power spectral density, filtering, and the like. The long-term evolution or new radio time-domain signal on the right can first undergo crest factor reduction processing to adjust the peak-to-average power ratio, but can undergo frequency processing such as filtering, and finally output to be compared with the processed time-domain narrowband IoT on the left The signals are combined.

[0089] Above about figure 1 The described method 100 of the present disclosure can be implemented by a computer program product. The computer program product has computer program code included thereon, which when executed by the processor causes the processor to execute figure 1 The method 100 of the present disclosure is described.

[0090] The present disclosure also provides a memory containing the computer program product mentioned above, which includes a machine-readable medium and a machine-readable transmission medium. Machine-readable media can also be referred to as computer-readable media, and can include machine-readable storage media, such as magnetic disks, tapes, optical disks, phase change memory, or random access memory (RAM), read-only memory (ROM) , Flash memory devices, CD-ROMs, DVDs, Blu-ray discs and similar electronic memory terminal devices. The machine-readable transmission medium may also be referred to as a carrier, and may contain, for example, electrical, optical, radio, acoustic, or another form of propagated signal—such as carrier waves, infrared signals, and the like.

[0091] The technology described in this document can be implemented by various components, so that a device that realizes one or more functions of the corresponding device described by an embodiment not only includes the prior art components, but also includes components used to implement the The one or more functional components of the corresponding device are described, and it may contain separate components for each separate function, or may be configured to perform two or more functions. For example, these technologies can be implemented in hardware, firmware, software, or a combination thereof. For firmware or software, implementation can be made through modules (for example, procedures, functions, etc.) that perform the functions described herein.

[0092] The exemplary embodiments herein have been described above with reference to block diagrams and flowchart illustrations of methods and devices. It will be understood that each block illustrated in the block diagrams and flowcharts, and combinations of blocks illustrated in the block diagrams and flowcharts, can be implemented by various components including hardware, software, firmware, and combinations thereof, respectively. For example, in one embodiment, each block illustrated in the block diagrams and flowchart illustrations, and combinations of blocks in the block diagrams and flowchart illustrations, can be implemented by computer program instructions. These computer program instructions can be loaded on a general-purpose computer, a special-purpose computer, or other programmable data processing equipment to produce a machine, so that the instructions running on the computer or other programmable data processing equipment are created to implement the flowchart block or multiple The part of the function specified in the flowchart box.

[0093] Further, although the operations are depicted in a specific order, this should not be construed as requiring such operations to be performed in the specific order or sequential order shown or all the operations shown to be performed to obtain desired results. In some cases, multitasking and parallel processing can be beneficial. Likewise, although several specific implementation details are included in the above discussion, these should not be construed as limitations on the scope of the subject matter described herein, but literally translated as descriptions of features that can be specific to specific embodiments. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Furthermore, although features can be described above as acting in certain combinations, and even initially declared as such, one or more features from the declared combination can in some cases be removed from the combination and the declared The combination of can be directed to a sub-combination or a variant of the sub-combination.

[0094] It will be obvious to those skilled in the art that, as a technological advancement, the inventive concept can be implemented in various ways. The embodiments described above are given for the purpose of describing rather than limiting the present disclosure, and it is understood that modifications and variations may be adopted without departing from the spirit and scope of the present disclosure as easily understood by those skilled in the art. Such modifications and variations are deemed to be within the scope of the present disclosure and the appended claims. The protection scope of the present disclosure is defined by the appended claims.