Method and apparatus for wireless transmission, and method and apparatus for wireless reception

Abstract

Methods and techniques are described for increasing data rates with high error performance in wireless transmission. In particular, each complex symbol of a sequence of complex symbols is mapped to a respective subcarrier in a frequency division based system, which may be orthogonal or non-orthogonal frequency division multiplexing. The sequence is a concatenated sequence of N sequences of complex symbols, where N is an integer greater than 1, and each of the N sequences is a mapping of a data block onto the complex symbols of the respective sequence. The real part of the sequence is a first number c Re The elements are circularly shifted by a second number c Im The elements are circularly shifted by c Re and c Im are distinct integers equal to or greater than zero.

Description

Technical Field

[0001] The present disclosure generally relates to communications, and in some particular embodiments, to techniques for transmitting signals using dual - carrier modulation. Background

[0002] Wireless communications have been advancing over the last several decades. Global communication systems and local network systems recently use technologies based on orthogonal frequency - division multiplexing (OFDM).

[0003] In OFDM, data symbols are transmitted simultaneously over multiple sub - carriers. Here, a data symbol refers to a modulation symbol that can transmit one or more data bits depending on the modulation order. Simultaneously means within one OFDM symbol. An OFDM symbol is obtained by mapping modulation symbols to the sub - carriers of the transmission band and then transforming the sub - carriers by an inverse Fourier transform (IFFT), or generally by an inverse orthogonal transform. Thereafter, the OFDM symbol is provided for transmission, at this time in the time domain. Before transmission, additional operations may be used, such as operations related to multiple - input multiple - output (MIMO) processing, or some further signal processing. Transmission may further include one or more of pulse shaping, amplification, and modulation to an appropriate carrier frequency.

[0004] For each OFDM symbol, a total of Nlog2M bits can be transmitted, where N and M are the number of subcarriers and the modulation order in a resource unit (RU), respectively. A resource unit is a unit of allocatable resource. For example, the smallest allocatable resource unit can include a plurality of subcarriers in one or more OFDM symbols (corresponding to an interval in the time domain). Here, the spectral efficiency of the OFDM system is given as log2M. In the IEEE (Institute of Electrical and Electronics Engineers) 802.11 (Wi-Fi) standard, for example, IEEE 802.11ax (Wi-Fi 6), different modulation and coding schemes (MCS) with varying modulation orders and coding rates are defined. For example, MCS0 is a scheme that uses binary phase shift keying (BPSK) (M = 2) and a coding rate of 1 / 2. In MCS0, only log2M = 1 bit can be transmitted per subcarrier. Therefore, this scheme may be used when the channel condition is poor or the received signal strength is low. To further improve reliability, dual carrier modulation (DCM) is introduced, in which the same input bits are modulated with a pair of subcarriers having the same or different constellations. However, one of the main drawbacks of DCM is that the data rate is reduced by half.

[0005] Improving the efficiency of methods such as DCM is a difficult task. Overview

[0006] Methods and techniques will be described that enable improvement of data rate and error performance by using specific dual carrier modulation.

[0007] The present invention is defined by the independent claims. Some exemplary embodiments are provided by the dependent claims.

[0008] For example, a method for wireless transmission is provided, the method including mapping each complex symbol of a series of complex symbols to respective sub-carriers, the series being a concatenated series from N series of complex symbols, N being an integer greater than 1, each of the N series being a mapping of a data block to complex symbols of the respective series, and (ii) the real part of the series being the first number c Re only has elements that are circularly shifted, and / or (i) the imaginary part of the series being the second number c Im only has elements that are circularly shifted, c Re and c Im being different integers greater than or equal to zero.

[0009] Furthermore, a method for wireless reception of a data block is provided, the method including determining a data block from a series of complex symbols, each complex symbol of the series being received on respective sub-carriers, the series being a concatenated series from N series of complex symbols, N being an integer greater than 1, each of the N series being a mapping of a data block to complex symbols of the respective series, and (i) the real part of the series being the first number c Re only has elements that are circularly shifted, and / or (ii) the imaginary part of the series being the second number c Im only has elements that are circularly shifted, c Re and c Im being different integers greater than or equal to zero.

[0010] According to a further embodiment, an apparatus for transmission and reception of a signal is provided, including a processing circuit configured to perform the steps of each of the above-described transmission method and reception method, and a transceiver configured to receive or transmit a signal.

[0011] The above-described circuit can be any circuit, such as a processing circuit including one or more processors and / or other circuit elements.

[0012] These and other features and characteristics of the subject matter disclosed herein, as well as the methods of operation and functions of the related elements and components of the structure and the economies of manufacture, will become more apparent upon consideration of the following description and the appended claims, which form a part of this specification. However, it should be expressly understood that the drawings are for the purpose of illustration and description only and are not intended as a definition of the limits of the disclosed subject matter. As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

Brief Description of the Drawings

[0013] An understanding of the nature and advantages of the various embodiments can be realized by referring to the following figures.

Figure 1

Figure 2

Figure 3a

Figure 3b

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9a

Figure 9b

Figure 10a

Figure 10b

[0014] Like reference numerals and signs in the various figures indicate like elements, according to some exemplary embodiments. Detailed description

[0015] For the purposes of the following description, the terms "end," "upper," "lower," "right," "left," "vertical," "horizontal," "top," "bottom," "lateral," "longitudinal," and derivatives thereof are to be considered as related to the disclosed subject matter as oriented in the figures of the drawings. However, it should be understood that the disclosed subject matter can assume various alternative variations and step sequences, unless explicitly specified to the contrary. It should also be understood that the specific devices and processes shown in the attached drawings and described in the following specification are merely exemplary embodiments or aspects of the disclosed subject matter. Accordingly, specific dimensions and other physical characteristics related to the embodiments or aspects disclosed herein should not be considered limiting, unless otherwise indicated.

[0016] Any aspect, component, element, structure, act, step, function, instruction, or the like used in this specification should not be construed as important or essential unless explicitly stated otherwise. Also, as used in this specification, the articles "a" and "an" are intended to include one or more items and can be used interchangeably with "one or more" and "at least one". Further, as used in this specification, the term "set" is intended to include one or more items (e.g., related items, unrelated items, combinations of related and unrelated items, etc.) and can be used interchangeably with "one or more" or "at least one". The term "one" or similar language is used when only one item is intended. Also, the terms "has", "have", "having", etc., as used in this specification are intended to be open-ended terms. Further, the phrase "based on" is intended to mean "at least partially based on" unless explicitly stated otherwise.

[0017] FIG. 1 shows an exemplary communication system CS, where Tx represents a transmitter and Rx represents a receiver. The transmitter Tx can transmit signals to the receiver Rx via an interface If. The interface can be, for example, a wireless interface. The interface can be specified by resources used for transmission and reception by the transmitter Tx and the receiver Rx. Such resources can be defined in one or more (or all) of the time domain, frequency domain, code domain, and spatial domain. Note that in general, the "transmitter" and "receiver" may be integrated within the same device. In other words, the devices Tx and Rx in FIG. 1 may each also include the functions of Rx and Tx.

[0018] The present disclosure is not limited to any particular embodiment of a transmitter Tx, receiver Rx, and / or interface If. However, the present disclosure can be readily applied with some existing communication systems, to the extension of such systems, or to new communication systems. Exemplary existing communication systems can be, for example, 5G New Radio (NR) of the current or future release, and / or IEEE 802.11-based systems such as the recently studied IEEE 802.11be.

[0019] As described in the background section, OFDM is a broadband multi-carrier transmission technology that is currently quite popular and is used in many standards such as IEEE802.11 (Wi-Fi), LTE (Long Term Evolution, the fourth generation, a 4G mobile communication system), and New Radio (NR, belonging to the fifth generation, 5G). In OFDM, the frequency band is divided into sub-bands, and these bands are called sub-carriers. The data symbols obtained by mapping the received bits to a constellation are simultaneously transmitted on these sub-carriers. A certain number of sub-carriers form a resource unit (RU). For example, an RU may include 26, 52, 106, 242, 484, or 996 sub-carriers. In Wi-Fi standards such as IEEE802.11ax (Wi-Fi6), there are multiple MCSs that can adjust the data rate and communication range. For example, MCS0 corresponds to BPSK with a coding rate of 1 / 2 and provides the most reliable communication and the lowest data rate among all MCSs. To further expand the communication range and improve the error performance in Wi-Fi, DCM is introduced at the expense of halving the data rate. It should be noted that the present disclosure can be easily applied to an OFDM system, but is not limited thereto. It is considered that the present disclosure can be generally applied to other methods such as frequency division multiplexing (FDM). OFDM or FDM is not limited to using an FFT, and a discrete Fourier transform (DFT) or other transforms may be used instead. On the receiver side, a signal in the time domain is received. The samples belonging to an OFDM symbol are converted by a (forward) transform such as a fast Fourier transform. Thereby, the modulated symbols mapped to the sub-carriers are obtained and demapped. Dual Carrier Modulation (DCM)

[0020] DCM is a modulation method that can be applied to an OFDM-based transmission method. DCM is included in the IEEE802.11ax standard and is applied in MCS0, 1, 3, and 4. In DCM, an RU of size N (for example, N sub-carriers) is divided into two parts.

[0021] FIG. 2 shows an exemplary mapping scheme of DCM-MCS0, i.e., DCM based on BPSK.

[0022] As shown in FIG. 2, the data symbols (x n and x m ) in the first half and the second half of the RU are determined by the same input bits, where n ∈ {1, …, N / 2} and m = N / 2 + n are the subcarrier indices in the first half and the second half of the RU, respectively. It should be noted that the same modulation scheme or different modulation schemes can be used to map the input bits to the data symbols in the first half and the second half of the RU. The term modulation here refers to mapping one or more bits to one of the multiple signal points given by the modulation scheme. The arrangement of the signal points in the modulation scheme is sometimes referred to as a constellation. In the case of BPSK, 1 bit of data is mapped to 1 data symbol (modulation symbol). In BPSK, the two possible signal points are usually antipodal and represent two respective phases that differ from each other by π (180°).

[0023] More specifically, according to DCM-MCS0, N / 2 groups of bits are each mapped to the first N / 2 subcarriers (e.g., the first N / 2 subcarriers if the subcarriers are ordered according to their indices). Further, the same N / 2 groups of bits are each mapped to the second N / 2 subcarriers (e.g., the last N / 2 subcarriers if the subcarriers are ordered according to their indices). In this case, since BPSK mapping is applied, the group size is 1, which means that each of the N / 2 groups contains 1 bit. In other words, the N input bits are divided into two branches. In the first branch, N / 2 bits are mapped to the data symbol x n by the first BPSK mapping, and in the second branch, the remaining N / 2 bits are mapped to the data symbol x mis mapped to.

[0024] DCM transmits the same information on two different subcarriers of OFDM, providing reliable communication and expanding the communication range. However, for the same reason, the conventional DCM method halves the data rate of any MCS, which is a very important measurement criterion in wireless communication networks.

[0025] Data rate is one of the important measurement criteria for efficiency in existing wireless communication networks. However, as the data rate increases in a system, the error performance usually deteriorates. As described above, in Wi-Fi technologies such as IEEE802.11ax, there are several MCSs to adjust the data rate and reliability. For example, MCS0 is the most reliable mode, but its data rate is low compared to higher layer modulation schemes. The DCM technique can improve the reliability of the MCS, and thus can also expand the communication range. However, the DCM technique may reduce the data rate. In future wireless communication technologies aimed at providing very high data rates, such as IEEE802.11be, it is desirable to avoid or reduce the reduction of the data rate. Detailed exemplary embodiments and variations

[0026] To make more spectrum available, in the draft of Wi-Fi7, a new frequency band operating at 6GHz, called the indoor-only low power indoor (LPI) channel, has been introduced. The duplexing mode (abbreviated as DUP) is a technique for duplexing the transmitted signal with additional frequency resources. Such an approach has been proposed to expand the range of the LPI channel. The DUP mode can be used with DCM-MCS, but it halves the data rate of DCM-MCS.

[0027] To improve performance, in some embodiments presented herein, DCM and DUP mode DCM are fused with space-time block codes using coordinate interleaving. A symbol assignment technique designed considering the data field of Wi-Fi technology is proposed to provide an improvement in error performance. Further, in addition to or instead of DUP mode DCM, power pattern index modulation is provided, which can carry additional bits by the index of the power pattern of subcarriers.

[0028] FIG. 3a shows a transmitting device 350 according to some exemplary embodiments. The transmitting device 350 may be part of any wireless communication device such as a STA or an AP, or generally, a base station or a terminal. The transmitting device 350 includes a memory 310, a processing circuit 320, and a wireless transceiver 330 (or a wireless transmitter 330), which may be able to communicate with each other via a bus 301. The transmitting device 350 may further include a user interface 340. However, depending on the application, the user interface 340 may be unnecessary (for example, some devices for machine-to-machine communication, etc.).

[0029] The memory 310 can store a plurality of firmware or software modules implementing some embodiments of the present disclosure. The memory 310 can be read by the processing circuit 320. Thus, the processing circuit can be configured to execute the firmware / software implementing the embodiments. The processing circuit 320 can include one or more processors, and the processors prepare data blocks for transmission during operation. In particular, the circuit 320 is configured to map each complex symbol of a series of complex symbols to respective subcarriers. The series is a series obtained by concatenating N series of complex symbols, and N is an integer greater than 1. Each of the N series is a mapping of a data block to the complex symbols of the respective series. Further, the real part of the series is the first number c ReOnly the elements are circularly shifted. Alternatively or in addition, the imaginary part of the series is the second number c Im Only the elements are circularly shifted. Here, c Re and c Im are different integers greater than or equal to zero. The data block may be a block of data provided for transmission from an upper layer, or may be a block of encoded data. For example, the data block may be encoded by any kind of forward error coding.

[0030] During operation, the wireless transceiver 330 transmits a transmission signal generated by mapping and possibly further operations. Such further operations can include inverse transforms such as IFFT or IDCT according to a desired (orthogonal or non-orthogonal) frequency division multiplexing. Further, the transformed time-domain symbols may then be modulated onto an actual carrier wave, amplified, etc.

[0031] As described above, by program code, a processing circuit (e.g., including one or more processors) can operate as a dedicated computer programmed to execute the techniques disclosed herein. In FIG. 3a, the memory 310 is shown as being separated from the processing circuit. However, this is merely an example. In general, the memory 310 can be implemented within the processing circuit, e.g., within one or more processors. The term "memory" refers to any type of long-term, short-term, volatile, non-volatile, or other memory, and is not limited to any particular type of memory, the number of memories, or the type of medium in which the memory is stored.

[0032] The wireless transceiver 330 can operate according to some known resource multiplexing scheme and / or multi-user multiplexing scheme. Generally, any currently used scheme as employed in the IEEE802.11 framework or 5G / 6G framework is applicable. In particular, possible examples include OFDM, OFDMA, or non-orthogonal multiple access (NOMA), etc.

[0033] FIG. 10a shows an exemplary transmitter for OFDM. Correspondingly, a data block of bits is obtained for transmission. The bits can be obtained from pre-processing such as, for example, forward error coding, rate matching, CRC insertion, and / or multiplexing of data for different users. Next, they are parallelized in a serial to parallel module 1010 to match the size of the inverse transform to be taken. A modulator 1020 modulates the bits in the modulation symbols with a modulation such as BPSK or QPSK, nQAM, and performs a mapping of the modulation symbols to the sub-carriers to be converted into one OFDM symbol, as will be described below. Such mapping can correspond to the mapping by any of the embodiments described below. After modulation 1020, an inverse transform (here, exemplarily, an inverse fast Fourier transform, IFFT) 1030 is applied to obtain an OFDM symbol. A cyclic prefix (CP) may be added to the OFDM symbol in a CP module 1040. After the serial to parallel conversion 1050, the signal is passed to the front end for transmission. This can include a digital to analog conversion 1060 and further amplification or signal shaping steps. It should be noted that the transceiver modules 1030 to 1060 are merely exemplary and the present disclosure is not limited thereto. There may be additional modules, or these modules may have additional functions such as PAPR reduction. As described above, OFDM is also merely an exemplary type of wireless transmission. Generally, alternative techniques such as NOMA are possible.

[0034] In some embodiments, the processing circuitry that performs the functions described herein can be integrated within an integrated circuit on a single chip. The output of the processing circuitry is a signal combined in the time domain. It can be a discrete signal that can be provided to transceiver 330 for the processing circuitry to transmit. The processing circuitry can also implement a control function to control transceiver 330 to transmit a signal. Transceiver 330 is configured (e.g., by the processing circuitry) to transmit a signal by symbols that carry the generated signal. For example, processing circuitry 320 may configure (control) transceiver 330 to transmit a signal via bus 301. The transceiver may be, for example, a wireless transceiver.

[0035] The DCM provides the same information on two separate subcarriers to increase the diversity order. The DUP mode further increases the diversity order by duplicating the DCM signal in an additional frequency band. However, the DUP mode doubles the frequency resources used by the DCM. Therefore, it uses more resources than the DCM at the same data rate. With the above-described transmitting device and its corresponding receiving device, it may be possible to increase the diversity order of these schemes without using additional resources or reducing the data rate. In some embodiments, the increase in the diversity order is achieved by separating data symbols into real and imaginary parts and distributing them to a plurality of subcarriers. The data symbols of the DCM signal using DCM or DUP are thus separated into real and imaginary parts. Then, the imaginary part of the symbol is circularly shifted by subcarriers so that the complexity (e.g., the complexity of the receiver) remains the same. Therefore, compared to using only DCM or DCM with DUP, all data symbols are distributed over more frequency resources. This may increase the diversity order and improve the error performance.

[0036] In an exemplary embodiment, DCM is applied, during which N SDThe RU having M data subcarriers is split into two parts. The data symbols (x n and x m ) in the first and second halves of the RU are determined by the same input bits to provide frequency diversity, where n ∈ {1, …, N SD / 2} and m = N SD / 2 + n are the subcarrier indices for the first and second halves of the RU respectively. Generally, the same or different mapping schemes can be used to map the input bits to data symbols. Finally, the overall data symbol vector can be obtained as

Number

Number

Number

[0037] In the LPI channel, to further expand the communication range for a single user (SU), the DUP mode DCM can be applied. Thus, the DCM signal is duplicated in the frequency domain. The overall data symbol vector can be obtained as

Number

[0038] According to this embodiment, a diversity extension technique is provided that improves the performance of DCM using DCM and DUP modes while providing the same data rate. This technique can be referred to as coordinate interleaved (CI) DCM, abbreviated as CI-DCM. Correspondingly, when DCM and DUP modes are applied together with CI, CI-DUP-DCM can be provided. For example, assuming x = x1 = x2, for DCM and DUP mode DCM respectively, y = [x T , x T T , y = [x T , x T , x T , x T T . According to the CI method, the vector x is separated into real and imaginary parts for each element. Then, the imaginary part of x (x I ) is circularly shifted by only c elements. The a-th element of the new circularly shifted version of the imaginary data symbol vector is

Number

Number

[0039] The vector form of this circularly shifted data symbol is

Number

Number

Number

Number

Number

[0040] In FIGS. 4 and 5, for x = x1 = x2 and N SD = 1960, exemplary frame structures of DUP mode DCM and CI-DUP-DCM are shown respectively. The numbers above the frame structure represent the data sub-carrier indices from 1 to N SD = 1960 in this example. Comparing FIG. 4 with FIG. 5, it can be seen that the frame structure of CI-DUP-DCM is obtained by circularly shifting only the imaginary part of the DUP mode DCM signal by c = N SD / 8 = 245 elements.

[0041] In particular, FIG. 4 shows DUP mode DCM. The input of such DUP / DCM mapping is 490 elements x where l = 1, 2, …, 490 lThe vector x is a complex vector x having the following structure: x = 1 - 1960. This vector x is mapped four times onto consecutive subcarriers 1 - 1960. Specifically, according to DCM, the 490 elements are mapped twice, first onto subcarriers with indexes 1 - 460, and second onto subcarriers with indexes 461 - 980. Then, according to DUP mode, the DCM mapping is repeated for subcarrier indexes 981 - 1960. In FIG. 4, for the sake of illustration, the vector x is shown split into its real and imaginary components. The real components (elements

number

number

[0042] Figure 5 illustrates the CI-DUP / DCM according to one embodiment. As can be seen, the real part of vector x (sequence of real parts of vector elements) is mapped similarly to the real parts of Figure 4. However, the imaginary part of vector x is cyclically shifted before the DUP / DCM mapping. Thus, by left shifting by c=245, the vector element x 246 ,x 247 ,…,x 490 ,x1,x2,…,x 245 Corresponding to

number

[0043] In other words, the mapped complex vectors (for DCM and DUP mode DCM respectively,

number

[0044] Each of the N series is a mapping of a data block to the complex symbols of the respective series. Note that FIG. 5 shows a simple case where the N series are the same. However, the present disclosure is not limited to such a method. For example, the mapping of the data block may be different, for example, different redundant versions representing the encoded data block, or may be scrambled or interleaved (compared to each other).

[0045] Furthermore (according to CI), the real part of the series is circularly shifted by only the first number c of elements Re Alternatively or additionally, the imaginary part of the series is circularly shifted by only the second number c of elements Im Here, c Re and c Im are different integers greater than or equal to zero. In the example of FIG. 5, the real part is not circularly shifted, the imaginary part is shifted by 245, and as a result c Re = 0 and c Im = 245. However, generally, the present disclosure is not limited to such a method. Similar advantages may be achieved by a relative shift between the real part and the imaginary part, whereby in some possible embodiments, the imaginary part is not shifted, but the real part is shifted. As long as the shifts are different for the real part and the imaginary part, both parts may be shifted.

[0046] In the DUP mode DCM, the l-th complex data symbol (x l ) is transmitted on four divided sub-carriers, but in FIG. 5, x l is transmitted on eight divided sub-carriers. Therefore, while providing the same data rate, the diversity order is improved. In the example of FIG. 5, the cyclic shift is the same for all four replicas of the imaginary part of the data block symbol. However, according to some embodiments, it is possible to vary the cyclic shift amount between the copies (replicas) of the data block symbol. In other words, DCM and / or DUP can apply different cyclic shift amounts for the first half and the second half of the symbol.

[0047] The symbol mappings in FIGS. 4 and 5 were performed for consecutive sub-carriers. However, generally, this should not be a limitation of the present disclosure. Rather, it may be beneficial to map the data block symbols to different, non-adjacent bands.

[0048] As described above, the number N of the N sequences can be 2 (in the case of DCM) or 4 (in the case of DUP / DCM). However, the present disclosure supports other values of N such as 3, 5,..., 8 or more. FIGS. 4 and 5 show the case where all N sequences are the same (x = x1 = x2). However, as also described above, in some embodiments, two or more of the N sequences are different from each other (x1 ≠ x2). There may be three or more different sequences (vectors).

[0049] In some exemplary embodiments, the second half of the complex sequence mapped to the sub-carriers is a repetition of the first half of the sequence. However, in other embodiments, the two halves may be different representations of the same data with respect to encoding and / or modulation. With respect to encoding, different representations may be different redundancy versions, or different scrambled versions of the interleaved versions of the data.

[0050] Regarding modulation, in some embodiments, the modulation scheme can be obtained by dividing a phase shift keying (PSK) or quadrature amplitude modulation (QAM) scheme into groups having M symbols and / or are related to each other by rotation in the complex plane. For example, modulation schemes (or modes) include binary phase shift keying (BPSK) and quadrature binary phase shift keying (QBPSK). This is shown in FIG. 7, that is, the two modes of the BPSK constellation are obtained as X1 = {1, -1} and X2 = {j, -j} by the original BPSK symbol and its rotated version, respectively (where j represents the imaginary unit, that is, j 2 = -1). In other words, the symbols of the first modulation scheme may be the BPSK symbols {1, -1}, and the symbols of the second modulation may be obtained by rotating the BPSK symbols by π / 2 in the complex plane. The symbols of the first and second modulation schemes may be obtained by dividing the symbols of QPSK (or, more generally, a modulation scheme having four symbols) into two groups, each of which corresponds to one of the first and second modulation schemes. For example, the first BPSK mapping maps 0 and 1 to phases 0 and π, while the second BPSK mapping maps 0 and 1 to phases π / 2 and 3π / 2 corresponding to the two BPSK constellations described above. Note that QPSK, and the corresponding two BPSK mappings, may be rotated by the same fixed angle, for example, π / 4. Next, the first BPSK mapping maps 0 and 1 to phases π / 2 and 5π / 2, while the second BPSK mapping maps 0 and 1 to phases 3π / 2 and 7π / 2. These are examples of ways to obtain two modulation schemes (Q = 2), each having two symbols (M = 2).

[0051] Generally (i.e., when Q ≥ 2 and M ≥ 2), a Q modulation scheme can be obtained by dividing a constellation including at least "Q × M" symbols. For example, the symbols of 16-QAM can be divided into four groups each having four symbols, eight groups each having two symbols, or two groups each having eight symbols. This is not limited to 16-QAM. For example, symbols of any QAM (4-QAM, 8-QAM, 16-QAM, 32-QAM, 64-QAM, 256-QAM, etc.) or PSK modulation (4-PSK, 8-PSK, 16-PSK, etc.) may be divided. Alternatively, a new modulation scheme can be obtained from a given modulation scheme by rotating the constellation in the complex plane (e.g., rotating each symbol). The given modulation scheme and the rotated modulation scheme will have the same number of symbols.

[0052] According to one embodiment, the absolute value of the difference between the first number and the second number is

Number

[0053] FIG. 3b shows a receiving device 355 according to some exemplary embodiments. The receiving device 355 includes a memory 315, a processing circuit 325, and a wireless transceiver 335 (or a wireless receiver 330), which may be able to communicate with each other via a bus 306. The receiving device 355 may further include a user interface 345. However, depending on the application, the user interface 345 may be unnecessary (e.g., some devices for machine-to-machine communication, etc.).

[0054] In some embodiments, the processing circuit 325 that performs the functions described herein can be integrated within an integrated circuit on a single chip. The processing circuit can also implement a control function that controls the transceiver 335 to receive signals. The transceiver 330 is configured (e.g., by the processing circuit) to receive signals and obtain the symbols carried by the signals. For example, the processing circuit 320 may configure (control) the transceiver 330 to receive signals via the bus 301. The transceiver can be, for example, a wireless transceiver that conforms to some standard or predefined rules in order to be compatible with a transmitter, for example, the transmitter described with reference to FIG. 3a.

[0055] During operation, the transceiver / receiver 335 receives a transmission signal. The processing circuit 325 can include one or more processors, and the processors are configured to determine a data block from a series of complex symbols. Further, corresponding to the transmitter described above, each complex symbol of the series is received at a respective subcarrier. The series is a series formed by concatenating N series of complex symbols, where N is an integer greater than 1. Each of the N series is a mapping of the data block to the complex symbols of the respective series. The real part of the series is circularly shifted by an element by a first number c Re and / or the imaginary part of the series is circularly shifted by an element by a second number c Im Here, c Re and c Im are different integers greater than or equal to zero.

[0056] Generally, in a receiver, before the above-described processing, the signal can be received via one or more antennas of the receiver, amplified, and converted to the frequency domain by a conversion such as an FFT (Fast Fourier Transform) or DFT (Discrete Fourier Transform) corresponding to the inverse transformation applied by the encoder. After performing the fast Fourier transform (FFT), the received signal at the a-th subcarrier is

Equation

Number

Number

Number

Number

Number

Number

[0057] Perform single-symbol ML decoding

Number

[0058] Figure 10b shows an exemplary reception that is compatible with the transmitter described above with reference to Figure 3a. The signal is received via an antenna and converted from the analog domain to the digital domain by an analog-to-digital conversion module 1065. Next, the digital symbols are paralleled by a serial-to-parallel conversion module 1055. The cyclic prefix is removed by a CP module 1045. Thereafter, conversion is performed by a module 1035. In this example corresponding to Figure 3a, the conversion is an FFT. After the FFT, demodulation 1025 is performed. Demodulation can include demapping from subcarriers and some detection algorithm, as will be described in more detail later. Demodulation can be any of the embodiments and exemplary embodiments described later. After demodulation 1025, a parallel-to-serial module 1015 can serialize the demodulated bits into a data block and further process this. For example, forward error correction decoding, error detection, etc. may be performed. Power Pattern Index Modulation

[0059] Alternatively, or in addition to the application of CI to DCM or DCM / DUP, power pattern index modulation (PPIM) can be applied. Power pattern index modulation can help increase the number of transmitted bits without increasing the modulation order.

[0060] Figure 6 shows such power pattern index modulation. In particular, Figure 6 shows exemplary subcarriers having indices a, b, a + 2c, b + 2c, a + 4c, b + 4c, a + 6c, b + 6c, to which the symbol x a , in particular its real part

Number

Number

[0061] The subcarriers are determined as shown above according to CI-DUP-DCM. Thus, FIG. 6 shows the subcarriers as being continuous, but as can be seen from the subcarrier indices, they are not actually adjacent. According to this exemplary embodiment, the power pattern has a length equal to twice the number of "repeated" complex symbols (for the real and imaginary parts), i.e., 4 in the case of DCM and 8 in the case of DCM / DUP. However, this embodiment is merely exemplary and is not limited to DCM and / or DCM+DUP. It is also possible to generally map complex symbols to a plurality of subcarriers, and the plurality may be 3, 5, 6, 7, 8, or more. Therefore, the pattern can have a length equal to twice the number of such complex symbols. Such combinations of DCM, DCM+DUP (also denoted as DCM / DUP herein), or other types of multi-symbol transmissions with data transmission based on the power pattern.

[0062] Note that generally, the length of the pattern does not have to be the same as twice the number of complex symbols. It can be shorter or longer. The relationship between the subcarriers and the power pattern (how the power pattern is mapped to the subcarriers) may be pre-configured and known to the receiver and transmitter in advance, for example, by standard or preceding signaling.

[0063] In this example, two power levels, namely, high level (P1) and low level (P2), are defined. As can be seen from the lower figure of the sub-carrier column in FIG. 6, in this example, P1 > P2. In this example, the complex symbol is repeated 4 times and has two parts (real part and imaginary part). Therefore, there are 8 imaginary or real parts with configurable power levels. According to the exemplary PPIM shown in FIG. 6, 1 bit of data to be carried is mapped to one power pattern. In particular, the value 0 of the data bit ("bit 0") is encoded into the first power pattern P1, P2, P2, P1, P1, P2, P2, P1, and the value 1 of the data bit ("bit 1") is encoded into the second power pattern P2, P2, P2, P2, P2, P1, P1, P2. In this example, the first power pattern and the second power pattern are complementary, which can provide the advantages of high (Hamming) distance and thus improved error rate. However, the present disclosure is not limited to such complementary patterns, and generally, the patterns used do not need to be complementary. Further, in this example, two power patterns having a length of 8 bits are used. However, the present disclosure is not limited to such patterns. There may be three or more patterns, and the patterns may be longer or shorter.

[0064] More specifically, to implement the PPIM on DCM / DUP, the square root of the determined power pattern p is multiplied by the a-th data symbol vector

Number

Number

[0065] In this example, for CI-DCM and CI-DUP-DCM respectively, a total of 2 4 and 2 8 different power patterns can be created, because the a-th data symbol (x a ) is repeated with 4 and 8 separated sub-carriers. To obtain diversity orders of 4 and 8 for CI-DCM and CI-DUP-DCM respectively, only 2 power patterns can be employed. Therefore, as can be seen from FIG. 6, according to one additional bit, one power pattern is determined from the 2 patterns for x a .

[0066] Similar to DCM and DCM / DUP, PPIM can also be used as a downlink non-orthogonal multiple access (DL-NOMA) scheme. In this scheme, information is transmitted by the data symbols in CI-DCM or CI-DUP-DCM and the indexes of the power patterns for User 1 and User 2 respectively. Note that in this NOMA scheme, the length of the power pattern does not need to be 4 or 8. Its length can be adjusted according to the needs of User 2 and generally can be assigned to different users according to their channel quality, priority, the amount of data to be transmitted, etc. When the length is increased, the data rate decreases and the reliability improves. On the other hand, when the length is shortened, the data rate increases and the reliability deteriorates. In such applications, different users can decode the data independently.

[0067] The above examples of PPIM are merely illustrative. Generally, the underlying technique is to encode data in the power levels of the real and / or imaginary parts of data symbols that are repeated a plurality of times (for example, 2 times in the case of DCM, 4 times in the case of DCM / DUP, but not limited to these numbers). Next, data encoding by PPIM can generally include expressing two bit values in two respective power level sequences, encoding the bits of the data in the power level sequences, and mapping the power level sequences of the encoded data to the real and / or imaginary power.

[0068] In some embodiments, each of the two power level sequences is a sequence of two or more power levels from a predefined set of power levels, and the predefined set of power levels includes at least two different power levels. In the above example, there are only two power levels. However, by employing more power levels, it is possible to further increase the data rate.

[0069] FIG. 8 shows a block diagram illustrating an exemplary transmitter embodiment. In particular, m_x is the number of bits transmitted by a data symbol (for example, by DCM, DCM / DUP, DCM-CI, DCM / DUP-CI, etc.), and m_p is the number of bits transmitted by the index of the power pattern. In this exemplary embodiment, m_x = G_x * is log2(M), where M is the number of modulation constellation points (corresponding to the modulation order). For example, M = 2 in the case of BPSK, M = 4 in the case of QPSK, and so on. Further, G_x is the number of data symbols to be mapped to subcarriers. For example, G_x = N_SD in the case of MCS, G_x = N_SD / 2 in the case of DCM using DCM and CI, and G_x = N_SD / 4 in the case of DUP mode DCM using DUP mode DCM and CI. In FIG. 5, G_x = N_SD / 4. The number of bits transmitted by one data symbol is g_x = log2(M).

[0070] In other words, the bit splitter 810 provides g_x bits to each symbol selector in order to perform modulation (such as BPSK or QPSK). The gx bits may be the same, i.e., the splitter may actually provide the same part of the g_x bits to each branch. In each branch, symbol selectors 822, 824 (generally, G_x symbol selectors) generate modulation symbols x_1, …, x_{G_x}. These modulation symbols are then mapped to subcarriers as described above, for example, based on MCS, DCM, DCM / DUP, DCM-CI, or DCM / DUP-CI.

[0071] Furthermore, G_p is the number of all selected power patterns. Here, m_p = G_p * is log2(P), where P is the number of all possible power patterns (where possible refers to the power patterns used in PPIM for encoding bits or symbols). In FIG. 6, the power patterns are [P1, P2, P2, P1, P1, P2, P2, P1] and [P2, P1, P1, P2, P2, P1, P1, P2]. This means that P = 2. There are only two power patterns. As described above, g_p is the number of bits transmitted by the index of one selected power pattern, and g_p = log2(P). In FIG. 6, g_p = 1 bit. In FIG. 6, for each data symbol, a power pattern of length 8 is selected, and each data symbol is repeated over 8 subcarriers, so G_p = N_SD / 4. For example, in the DUP mode DCM using CI, there are a total of N_SD / 4 data symbols. The length of the power pattern does not necessarily have to be 8 as described above.

[0072] For example, for each data symbol, two power patterns of length 4 can be selected. Therefore, more bits can be transmitted. Finally, the total number of transmitted bits by the index of the power pattern is m_p = G_p *It is log2(P). p_1 and p_{G_p} are power patterns selected according to the input bits. The power patterns are selected by respective power pattern selectors 832 and 834.

[0073] Note that in the example described above, the data was encoded not only in the real part but also in the imaginary part of the modulation symbol. However, the present disclosure is not limited to this, and generally, the data may be encoded only in one of the components (for example, leaving the default value that can be used for channel estimation in the other component). Alternatively, both the imaginary part and the real part may be encoded with the same power given by the data to be encoded. This approach may be more robust, but there is a possibility that the data rate may decrease.

[0074] In the PPIM OFDM block generator 850, the modulation symbol is mapped to subcarriers as described above, for example, using DCM and CI or DCM+DUP and CI, or generally according to the indices of the provided symbols x and power patterns p. Next, in the IFFT block 860, an OFDM symbol is generated by inverse-transforming the subcarriers. After adding a cyclic prefix, the OFDM symbol is further provided to the front end of the transmitter and transmitted.

[0075] Regarding the advantages, by applying CI in combination with DCM / DUP as described above, it may be possible to allocate each data symbol to more resources than the DUP mode DCM or DCM alone. Compared with the DUP mode DCM, in this application, more subcarriers are utilized to transmit the same information, so higher reliability is provided. The CI-DCM / DUP described above provides higher reliability than the DUP mode DCM, but the decoding complexity remains the same. By adding and applying PPIM, the data rate can be further increased. Such index modulation (IM) employs the index of the subcarrier power pattern to transmit additional bits. All possible power patterns (for example, 2 as in the example of FIG. 6)8 Rather than using (), further robustness and diversity can be achieved by selecting only a relatively small subset (e.g., 2 as in the example of FIG. 2). By increasing the diversity order of these schemes, the communication range may be further extended, which may be desirable especially for LPI channels. The combination of OFDM and space-time block coding with coordinate interleaved DCM / DUP or DCM can also be effective because it is compatible with Wi-Fi technology.

[0076] Corresponding to the above-described transmission device and reception device, a communication method for wireless transmission(s) executed by the transmission device and the reception device is provided. As shown in FIG. 3a, the transmission method for wireless transmission of a data block includes obtaining (910) a data block to be encoded. Such a data block is, for example, a block of bits representing encoded data such as FEC-encoded data. Such data can be further represented as modulation symbols of modulation of order 2 (such as BPSK) or modulation of order 4 (such as QPSK), or modulation of higher order (such as nPSK modulation or nQAM modulation). Generally, the modulation symbols are complex symbols.

[0077] The method can further include mapping (920) each complex symbol of a series of complex symbols to respective subcarriers, where the series is a concatenated series from N series of complex symbols, N is an integer greater than 1, and each of the N series is a mapping of a data block to the complex symbols of the respective series. This corresponds to DCM or DCM / DUP, or generally modulation that repeats each symbol multiple times with respect to frequency. Further, the real part of the series is circularly shifted (930) by only an element of the first number c Re The imaginary part of the series is circularly shifted (930) by only an element of the second number c Im Here, c Re and c Imare different integers greater than or equal to zero. The mutual shift between the imaginary part and the real part corresponds to CI. The amount of shift of either the imaginary part or the real part may be zero, i.e., only one component (imaginary part, real part) of the series is cyclically shifted. Note that the cyclically shifted series may be a series that combines multiple (N) versions of a smaller series, or may be applied to a smaller series.

[0078] Optionally, as described above, PPIM940 may be applied to encode additional bits using the power pattern. Finally, a signal representing such DCM / DUP-CI mapped data is transmitted (950). The transmission here can include various different steps. For example, after mapping to subcarriers, an IFFT may be employed to generate a frequency division multiplexed symbol (such as an OFDM symbol, or a symbol generated by a non-orthogonal frequency division scheme). Any system that maps modulation symbols to different subcarriers can be applied. Techniques for reducing PAPR may be applied, a cyclic prefix (CP) may be included between symbols, beamforming or space-time block coding, or other forms or spatial diversity may be added by any of the known techniques. Further, waveform shaping and amplification may be applied. As will be apparent to those skilled in the art, these steps are merely illustrative and there may be additional steps, and it is not necessary to apply all of the steps described above (such as PAPR reduction).

[0079] Corresponding to the receiving device described above, a communication method for wireless reception executed by the receiving device is provided. As shown in FIG. 3b, this method includes determining a data block from a series of complex symbols.

[0080] For example, a signal is received (960). Thereafter, demapping 970 and detection can be performed. Determining a data block may include maximum likelihood detection. Each complex symbol of a series is received at each respective sub-carrier. The series is a series obtained by concatenating N series of complex symbols, where N is an integer greater than 1, and each of the N series is a mapping of a data block to the complex symbols of each respective series. The real part of the series has the first few elements c Re circularly shifted by only the number of elements. The imaginary part of the series has the second few elements c Im circularly shifted by only the number of elements, where c Re and c Im are different integers greater than or equal to zero. In this way, a decoded data block can be obtained.

[0081] On the receiver side, an exhaustive search can be performed to find the best matching pattern. In the case of only two patterns, the search can include comparing the received pattern with each of the two possible patterns (encoding the bits with respective values 1 or 0) and determining that the pattern more similar to the received pattern was transmitted. The similarity can be determined by any known measurement criterion. Implementation in a WiFi framework

[0082] Embodiments of the present disclosure may be particularly suitable for Wi-Fi standards. For example, as described above, in IEEE802.11ax, DCM can be part of some modulation and coding schemes (MCS0). In future standards such as 802.11be, there may be additional MCSs that support DCM and / or DUP. The application of DCM and / or DUP, especially DCM / DUP using the CI (and optionally PPIM) described above, can be provided as additional MCSs, and these robust techniques can increase diversity and reduce the error rate, so it may be advantageous to apply them to lower MCSs (MCSs for lower SNR). Therefore, in such one or more additional MCSs, it may be desirable to apply a lower-order modulation (plural possible) to the symbols mapped according to DCM / DUP using DCM or CI. For example, in some embodiments, binary phase shift keying (BPSK) can be applied (optionally with rotation). In some embodiments, QPSK can be applied. The coding applied using these modulations can have a coding rate such as 1 / 2, for example. However, as described above, the present disclosure is not limited to the Wi-Fi framework and is generally applicable at higher levels of modulation and other coding rates.

[0083] In the context of Wi-Fi, DUP can be applied to 40, 80, or 160 symbols (e.g., DCM symbols) such that, for example, 80, 160, or 320 RUs are used. However, these are merely examples. To improve diversity, CI and / or PPIM as described above can be advantageously applied. After subcarrier mapping, some PAPR reduction method may be applied. Implementation in Software and Hardware

[0084] The methodologies described herein (on the transmitter side and the receiver side) can be implemented by various means depending on the application. For example, these methodologies can be implemented in hardware, an operating system, firmware, software, or any arbitrary combination of two or all of them. In the case of hardware implementation, any processing circuit that may include one or more processors can be used. For example, the hardware can include one or more of an application-specific integrated circuit (ASIC), a digital signal processor (DSP), a digital signal processing device (DSPD), a programmable logic device (PLD), a field programmable gate array (FPGA), a processor, a controller, any electronic device, or other electronic circuit units or elements designed to perform the functions described above.

[0085] When implemented as program code, the functions executed by the transmitting device (device) can be stored as one or more instructions or codes in a non-transitory computer-readable storage medium such as the memory 310 or any other type of storage. The computer-readable medium can include a physical computer storage medium, which can be any available medium accessible by a computer or generally a processing circuit 320. Such computer-readable media can include RAM, ROM, EEPROM, optical disk storage, magnetic disk storage, semiconductor storage, or other storage devices. Some specific non-limiting examples include compact discs (CDs), CD-ROMs, laser discs (registered trademark), optical discs, digital versatile discs (DVDs), Blu-ray (BD) discs, etc. Combinations of different storage media are also possible, that is, distributed storage and heterogeneous storage may be employed.

[0086] The above-described embodiments and exemplary implementations show several non-limiting examples. It is understood that various changes can be made without departing from the subject matter of the claims. For example, the examples can be modified to fit new systems and scenarios without departing from the main concepts described herein. In particular, the above embodiments and exemplary implementations are MIMO-compatible and can be applied to all MCSs. Selected embodiments and examples

[0087] According to one aspect, a method for wireless transmission of data blocks is provided, the method including mapping each complex symbol of a series of complex symbols to respective subcarriers, the series being a concatenated series from N series of complex symbols, N being an integer greater than 1, each of the N series being a mapping of a data block to the complex symbols of the respective series, (i) the real part of the series being cyclically shifted by a first number c Re only by the number of elements, and / or (ii) the imaginary part of the series being cyclically shifted by a second number c Im only by the number of elements, c Re and c Im being different integers greater than or equal to zero. The method can further include transmitting the mapped symbols.

[0088] For example, the number N of the N series is 2 or 4. In some embodiments, two or more of the N series are different from each other, thereby providing a higher data rate. In alternative embodiments, all of the N series are the same, thereby providing a higher diversity and, in some cases, a lower error rate.

[0089] According to one embodiment, the second half of the series is a repetition of the first half. In some exemplary implementations, the absolute value of the difference between the first number and the second number is

Number

[0090] For example, c Re or c Im is equal to zero.

[0091] The method may further include encoding data to the power level of the real part and / or the imaginary part.

[0092] In an exemplary embodiment, encoding the data includes representing two bit values by two respective power level sequences, encoding the bits of the data into the power level sequences, and mapping the power level sequences of the encoded data to the Power level real part and / or the imaginary part.

[0093] For example, each of the two power level sequences is a sequence of two or more power levels from a predefined set of power levels, and the predefined set of power levels includes at least two different power levels.

[0094] In some exemplary embodiments, the wireless transmission of the data block is non-orthogonal multiple access NOMA. In some exemplary embodiments, the wireless transmission of the data block is OFDM.

[0095] According to one aspect, a method for wireless reception of a data block is provided, the method including determining a data block from a sequence of complex symbols, each complex symbol of the sequence being received on a respective subcarrier, the sequence being a concatenated sequence from N sequences of complex symbols, N being an integer greater than 1, each of the N sequences being a mapping of the data block to the complex symbols of the respective sequence, (i) the real part of the sequence being circularly shifted by a first number c Re by only the elements, and / or (ii) the imaginary part of the sequence being circularly shifted by a second number c Im by only the elements, c Re and c Imis a different integer equal to or greater than zero. The method may further include receiving a signal including a sequence of complex symbols.

[0096] For example, determining a data block includes determining the values of the data symbols of the data block by performing maximum likelihood detection.

[0097] In particular, determining a data block includes determining the values of the data symbols by performing individual maximum likelihood detections for each of one or more data symbols of the data block, where only different values of the data symbols are considered.

[0098] The modulation details described above also apply to the receiving method, as the receiving method processes the signal transmitted by the transmitter.

[0099] According to one aspect, an apparatus for wireless transmission of a data block, comprising a circuit configured to map each complex symbol of a sequence of complex symbols to a respective subcarrier, the sequence being a concatenated sequence from N sequences of complex symbols, N being an integer greater than 1, each of the N sequences being a mapping of the data block to the complex symbols of the respective sequence, the real part of the sequence having only the elements of the first number c Re circularly shifted, and / or the imaginary part of the sequence having only the elements of the second number c Im circularly shifted, c Re and c Im being different integers equal to or greater than zero, and a transceiver configured to transmit the mapped complex symbols.

[0100] According to one aspect, an apparatus for wireless reception of data blocks, comprising a transceiver configured to receive a signal including a series of complex symbols, and a circuit configured to determine a data block from the series of complex symbols, wherein each complex symbol of the series is received at a respective subcarrier, the series being a concatenated series from N series of complex symbols, N being an integer greater than 1, each of the N series being a mapping of a data block to the complex symbols of the respective series, and the real part of the series being the first number c Re only the elements are circularly shifted, and / or the imaginary part of the series is the second number c Im only the elements are circularly shifted, c Re and c Im being different integers greater than or equal to zero, and a circuit. An apparatus for wireless reception.

[0101] The examples and exemplary embodiments described above for the method are equally applicable to the apparatus. In particular, the processing circuit can be further configured to perform one or more steps of the above-described embodiments and exemplary embodiments.

[0102] Furthermore, a computer program is provided that is stored on a non-transitory medium and includes code instructions that, when executed by a computer or a processing circuit, perform the steps of any of the above-described methods.

[0103] According to some embodiments, the processing circuit and / or the transceiver are integrated into an integrated circuit (IC).

[0104] The disclosed subject matter has been described in detail, for purposes of illustration, based on what is presently considered to be the most practical and preferred embodiments, but such details are for the purpose of that illustration only and the disclosed subject matter is not intended to be limited to the disclosed embodiments. On the contrary, it is to be understood that the disclosed subject matter is intended to cover modifications and equivalent arrangements within the spirit and scope of the appended claims. For example, it is contemplated that one or more features of any of the embodiments disclosed herein can be combined with one or more features of any other of the embodiments, to the extent possible. [Item of the invention] [Item 1] A method for wireless transmission of a data block, comprising: Mapping each complex symbol of a series of complex symbols to respective sub - carriers wherein the series is a concatenated series from N series of complex symbols, N is an integer greater than 1, and each of the N series is a mapping of the data block to the complex symbols of the respective series; the real part of the series has elements circularly shifted by a first number c Re and / or the imaginary part of the series has elements circularly shifted by a second number c Im where c c Re and c Im are different integers greater than or equal to zero, a method for wireless transmission. [Item 2] The method according to item 1, wherein the number N of the N series is 2 or 4. [Item 3] The method according to item 1 or 2, wherein two or more of the N series are different from each other. [Item 4] The method according to item 1 or 2, wherein all of the N series are the same. [Item 5] The method according to any one of items 1 to 4, wherein the second half of the series is a repetition of the first half of the series. [Item 6] The absolute value of the difference between the first number and the second number is |c Re -c Im |=N SD / 2N wherein NSD is the number of sub - carriers, the method according to any one of items 1 to 5. [Item 7] c Re or c Im is equal to zero, the method according to any one of items 1 to 6. [Item 8] Further comprising encoding data into the power level of the real part and / or the imaginary part the method according to any one of items 1 to 7. [Item 9] The step of encoding the data comprises representing two bit values by two respective power level series, encoding the bits of the data into the power level series, mapping the power level series of the encoded data to a power of the real part and / or the imaginary part the method according to item 8. [Item 10] Each of the two power level series is a series of two or more power levels from a predefined set of power levels, the predefined set of power levels includes at least two different power levels, the method according to item 8 or 9. [Item 11] The method according to any one of items 1 to 10, wherein the wireless transmission of the data block is non - orthogonal multiple access NOMA. [Item 12] A method for wireless reception of a data block, comprising: determining the data block from a series of complex symbols, wherein each complex symbol of the series is received at a respective sub-carrier, the series being a concatenated series from N series of complex symbols, N being an integer greater than 1, each of the N series being a mapping of the data block to the complex symbols of the respective series, the real part of the series being circularly shifted by an element by a first number c and / or the imaginary part of the series being circularly shifted by an element by a second number c, Re where c are different integers greater than or equal to zero, a method for wireless reception. [Item 13] Im The method according to item 12, wherein the step of determining the data block includes determining the value of the data symbol by performing individual maximum likelihood detection in which only different values of the data symbol are considered for each of one or more data symbols of the data block. c Re [Item 14] Im An apparatus for wireless transmission of a data block, comprising: a circuit configured to map each complex symbol of a series of complex symbols to a respective sub-carrier, the series being a concatenated series from N series of complex symbols, N being an integer greater than 1, each of the N series being a mapping of the data block to the complex symbols of the respective series, the real part of the series being circularly shifted by an element by a first number c and / or the imaginary part of the series being circularly shifted by an element by a second number c, where c are different integers greater than or equal to zero, a circuit, a transceiver configured to transmit the mapped complex symbols, an apparatus for wireless transmission. Re [Item 15] An apparatus for wireless reception of a data block, comprising: Im a transceiver configured to receive a signal including a series of complex symbols, c Re a circuit configured to determine the data block from the series of complex symbols, Im wherein each complex symbol of the series is received at a respective sub-carrier, the series being a concatenated series from N series of complex symbols, N being an integer greater than 1, each of the N series being a mapping of the data block to the complex symbols of the respective series, the real part of the series being circularly shifted by an element by a first number c and / or the imaginary part of the series being circularly shifted by an element by a second number c, ​ ​ ​ ​ ​ ​ Re ​ The imaginary part of the series has only elements that are circularly shifted by a second number c Im and c c Re is a different integer greater than or equal to zero, and a circuit Im comprising an apparatus for wireless reception .

Claims

1. A method for wireless transmission of a data block, comprising: mapping each complex symbol of a series of complex symbols to respective sub-carriers, wherein the series of complex symbols is obtained by concatenating N partial series of complex symbols, N being an integer greater than 1, and each of the N partial series is obtained by mapping the data block to the complex symbols of the respective partial series; The real part of the series is the first number c Ｒｅ only the elements are circularly shifted, and / or The imaginary part of the series is the second number c Ｉｍ only the elements are circularly shifted, c Ｒｅ and c Ｉｍ are different integers equal to or greater than zero, when the real part of the series is circularly shifted, the first number cRe is non-zero; when the imaginary part of the series is circularly shifted, the second number cIm is non-zero, the mapping step A method for wireless transmission, comprising:

2. The method according to claim 1, wherein the number N of the N partial series is 2 or 4.

3. The method according to claim 1 or 2, wherein two or more of the N partial series are different from each other.

4. The method according to claim 1 or 2, wherein all of the N partial series are the same.

5. The method according to any one of claims 1 to 4, wherein the second half of the series is a repetition of the first half of the series.

6. The absolute value of the difference between the first number and the second number is |c Ｒｅ -c Ｉｍ | = N ＳＤ / 2N where N ＳＤ is the number of the sub-carriers, the method according to any one of claims 1 to 5.

7. c Ｒｅ or c Ｉｍ The method according to any one of claims 1 to 6, wherein any one of them is equal to zero.

8. encoding data into the power level of the real part and / or the imaginary part, The method according to any one of claims 1 to 7, further comprising:

9. The step of encoding the data comprises: representing two bit values by two respective power level series; encoding the bits of the data into the power level series; mapping the power level series of the encoded data to the power level of the real part and / or the imaginary part. The method according to claim 8, comprising:

10. each of the two respective power level series is a series of two or more power levels from a predefined set of power levels; the predefined set of power levels includes at least two different power levels. The method according to claim 9.

11. The method according to any one of claims 1 to 10, wherein the wireless transmission of the data block is non-orthogonal multiple access (NOMA).

12. A method for wireless reception of a data block, comprising: determining the data block from a series of complex symbols, wherein each complex symbol of the series is received on a respective sub-carrier. The sequence of complex symbols is obtained by concatenating N partial sequences of complex symbols, where N is an integer greater than 1, and each of the N partial sequences is obtained by mapping the data block to the complex symbols of the respective partial sequence. the real part of the series is the first number c Ｒｅ only the elements are circularly shifted, and / or The imaginary part of the series is the second number c Ｉｍ only the elements are circularly shifted, c Ｒｅ and c Ｉｍ are different integers equal to or greater than zero, When the real part of the sequence is circularly shifted, the first number c Re is not zero. Determining that when the imaginary part of the sequence is circularly shifted, the second number c Im is not zero. A method for wireless reception, including the above steps.

13. The step of determining the data block includes determining the value of the data symbol by performing individual maximum likelihood detection for each of one or more data symbols of the data block, where only different values of the data symbol are considered. The method according to claim 12.

14. An apparatus for wireless transmission of a data block, comprising: A circuit configured to map each complex symbol of a sequence of complex symbols to a respective sub-carrier. The sequence of complex symbols is obtained by concatenating N partial sequences of complex symbols, where N is an integer greater than 1, and each of the N partial sequences is obtained by mapping the data block to the complex symbols of the respective partial sequence. the real part of said series is the first number c Ｒｅ only the elements are circularly shifted, and / or The imaginary part of the series is the second number c Ｉｍ only the elements are circularly shifted, c Ｒｅ and c Ｉｍ are different integers equal to or greater than zero, When the real part of the sequence is circularly shifted, the first number c Re is not zero. A circuit that when the imaginary part of the sequence is circularly shifted, the second number c Im is not zero, and A transceiver configured to transmit the mapped complex symbols. An apparatus for wireless transmission, comprising the above components.

15. An apparatus for wireless reception of a data block, comprising: A transceiver configured to receive a signal including a sequence of complex symbols. A circuit configured to determine the data block from the sequence of complex symbols. Each complex symbol of the sequence is received on a respective sub-carrier. The sequence of complex symbols is obtained by concatenating N partial sequences of complex symbols, where N is an integer greater than 1, and each of the N partial sequences is obtained by mapping the data block to the complex symbols of the respective partial sequence. the real part of said series is the first number c Ｒｅ only the elements are circularly shifted, and / or The imaginary part of the series is the second number c Ｉｍ only the elements are circularly shifted, c Ｒｅ and c Ｉｍ are different integers equal to or greater than zero, When the real part of the sequence is circularly shifted, the first number c Re is not zero. A circuit in which when the imaginary part of the series is circularly shifted, the second number cIm is not zero, and An apparatus for wireless reception, comprising.

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