Systems and methods for conjugate data modulation

Abstract

The present disclosure relates generally to wireless communications, and more particularly to systems and methods for modulating user data using conjugate data of time domain communications. In one embodiment, the method performed by a device includes: modulating user data into modulated user data elements; determining conjugate data elements, wherein each conjugate data element is a conjugate or anti-conjugate of a different modulated user data element; and transmitting a user data sequence including the modulated user data elements interleaved with the conjugate data elements in the time domain.

Description

Technical Field

[0001] The present disclosure relates generally to wireless communications, and more particularly, to systems and methods for modulating user data using conjugate data for time domain communications. Background Art

[0002] As the number of applications and services for digital data continues to explode, the demands and challenges on network resources and operators will continue to increase. Being able to achieve the various network performance characteristics required by future services is one of the main technical challenges facing service providers today.

[0003] Radio frequency (RF) circuits in wireless communications can generate phase noise (PN) due to factors such as jitter and instability of crystal oscillator circuits. Phase noise can be particularly sharp (e.g., relatively large) at higher frequency carrier frequencies. Phase noise can be detrimental to communications, for example, phase noise can interfere with symbol modulation and degrade the demodulation performance of a receiver. Current techniques for phase noise compensation (e.g., reduction) can require significant communications resources and processing power, but still fail to produce satisfactory results. Therefore, current techniques for phase noise compensation may not be entirely satisfactory. Summary of the invention

[0004] The exemplary embodiments disclosed herein are intended to solve problems related to one or more problems existing in the prior art, as well as to provide additional features, which will become apparent when combined with the accompanying drawings and by reference to the following detailed description. According to various embodiments, exemplary systems, methods, devices, and computer program products are disclosed herein. However, it should be understood that these embodiments are presented by way of example and not limitation, and it is apparent to those of ordinary skill in the art who read this disclosure that various modifications may be made to the disclosed embodiments while remaining within the scope of the present invention.

[0005] In one embodiment, a method performed by a device includes: modulating user data into modulated user data elements; determining conjugated data elements, wherein each conjugated data element is a conjugate or anti-conjugate of a different modulated user data element; and transmitting a user data sequence including the modulated user data elements interleaved with the conjugated data elements in a time domain.

[0006] In a further embodiment, a method performed by a device includes: receiving a user data sequence, wherein the user data sequence includes modulated user data elements interleaved with conjugate data elements, wherein each conjugate data element is a conjugate or a negative conjugate of a different modulated user data element; and demodulating the user data sequence to produce user data.

[0007] In a further embodiment, an apparatus comprises: a processor configured to: modulate user data into modulated user data elements, determine conjugate data elements, wherein each conjugate data element is a conjugate or anti-conjugate of a different modulated user data element; and a transmitter configured to: transmit in a time domain a user data sequence comprising the modulated user data elements interleaved with the conjugate data elements.

[0008] In a further embodiment, an apparatus comprises: a receiver configured to: receive a user data sequence, wherein the user data sequence comprises modulated user data elements interleaved with conjugate data elements, wherein each conjugate data element is a conjugate or anti-conjugate of a different modulated user data element; and a processor configured to demodulate the user data sequence to produce user data. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Various exemplary embodiments of the present invention are described in detail below with reference to the following drawings. The drawings are provided for illustrative purposes only and only depict exemplary embodiments of the present invention to facilitate the reader's understanding of the present invention. Therefore, the drawings should not be regarded as limiting the breadth, scope or applicability of the present invention. It should be noted that for clarity and ease of description, these figures are not necessarily drawn to scale.

[0010] Figure 1 An exemplary wireless communication network is shown in which the techniques disclosed herein may be implemented according to some embodiments.

[0011] Figure 2 A block diagram of an exemplary wireless communication system for sending and receiving wireless communication signals in accordance with some embodiments is shown.

[0012] Figure 3 is a conceptual block diagram of a fourth data sequence in the time domain according to some embodiments.

[0013] Figure 4 is a conceptual block diagram of a fourth data sequence in the time domain according to some embodiments.

[0014] Figure 5 is a conceptual block diagram of a fourth data sequence with a relatively long pilot sequence in the time domain according to some embodiments.

[0015] Figure 6 is a conceptual block diagram of a fourth data sequence in the time domain having a relatively short pilot sequence with greater user data throughput in accordance with some embodiments. DETAILED DESCRIPTION

[0016] Various exemplary embodiments of the present invention are described below with reference to the accompanying drawings to enable those of ordinary skill in the art to make and use the present invention. It is apparent to those of ordinary skill in the art that, after reading this disclosure, various changes or modifications may be made to the examples described herein without departing from the scope of the present invention. Therefore, the present invention is not limited to the exemplary embodiments and applications described and illustrated herein. In addition, the specific order or hierarchy of steps in the methods disclosed herein are merely exemplary methods. Based on design preferences, the specific order or hierarchy of steps of the disclosed methods or processes may be rearranged while remaining within the scope of the present invention. Therefore, it will be understood by those of ordinary skill in the art that the methods and techniques disclosed herein present various steps or actions in a sample order, and unless expressly stated, the present invention is not limited to the specific order or hierarchy presented.

[0017] The following discussion may refer to functional entities or processes similar to those mentioned above with respect to conventional communication systems. However, as will be appreciated by those of ordinary skill in the art, such conventional functional entities or processes do not perform the functions described below, and therefore, will require modification or specific configuration to perform one or more operations described below. In addition, those skilled in the art will be able to configure the functional entities to perform the operations described herein after reading this disclosure.

[0018] Figure 1 An exemplary wireless communication network 100 is shown according to an embodiment of the present disclosure, in which the techniques disclosed herein may be implemented. Such exemplary network 100 includes a base station 102 (hereinafter referred to as "BS 102") and a plurality of user equipments 104 (hereinafter referred to as "UE 104") (which may communicate with each other via respective communication links 110 (e.g., wireless communication channels)) and a set of conceptual cells 126, 130, 132, 134, 136, 138, and 140 covering a geographic area with network 101. Each UE 104 may undergo a random access procedure to join network 101. In Figure 1 1, BS 102 and each UE 104 are contained within the respective geographic boundaries of cell 126. Each of the other cells 130, 132, 134, 136, 138, and 140 may include at least one BS operating on its allocated bandwidth to provide adequate radio coverage to its target users. Thus, reference to a cell may be a shorthand reference to a BS having an associated coverage area or region (e.g., a cell). In some embodiments, a cell may be referred to interchangeably as a BS or a node.

[0019] For example, BS 102 can operate on an allocated channel transmission bandwidth (e.g., spectrum) to provide sufficient coverage to each UE 104. The spectrum can be adjusted to define a licensed range and / or an unlicensed range. BS 102 and each UE 104 can communicate via a downlink radio frame 118 and an uplink radio frame 124, respectively. Radio frames can also be more simply referred to as frames. Each frame 118 / 124 can also be divided into subframes 120 / 127 that can include data symbols 122 / 128. In the present disclosure, BS 102 and each UE 104 are generally described herein as non-limiting examples of devices that can practice the methods disclosed herein. According to various embodiments of the present invention, such devices are capable of wireless and / or wired communication. In some embodiments, a communication device can more specifically refer to a UE associated with a BS, and a communication node can more specifically refer to a BS associated with a UE.

[0020] Figure 2 A block diagram of an exemplary wireless communication system 200 for transmitting and receiving wireless communication signals (e.g., modulated signals such as orthogonal frequency division multiplexing (OFDM) / orthogonal frequency division multiple access (OFDMA) signals) according to some embodiments of the present invention is shown. System 200 may include components and elements configured to support known or conventional operating features that do not require detailed description herein. In an exemplary embodiment, as described above, system 200 may be used in applications such as Figure 1 Data symbols are sent and received in a wireless communication environment such as the wireless communication environment of the network 100 or the wireless communication environment of the network 100.

[0021] The system 200 generally includes a base station 202 (hereinafter referred to as "BS 202") and a user equipment 204 (hereinafter referred to as "UE 204"). The BS 202 includes a BS (base station) transceiver module 210, a BS antenna 212, a BS processor module 214, a BS memory module 216, and a network communication module 218, each of which is coupled and interconnected via a data communication bus 220 as needed. The UE 204 includes a UE (user equipment) transceiver module 230, a UE antenna 232, a UE memory module 234, and a UE processor module 236, each of which is coupled and interconnected via a data communication bus 240 as needed. The BS 202 communicates with the UE 204 via a communication channel 250, which can be any wireless channel or other medium known in the art suitable for transmitting data as described herein.

[0022] Those skilled in the art will appreciate that the system 200 may also include Figure 2Any number of modules outside the modules shown. It will be appreciated by those skilled in the art that the various illustrative blocks, modules, circuits, and processing logic described in conjunction with the embodiments disclosed herein can be implemented in hardware, computer-readable software, firmware, or any actual combination thereof. In order to clearly illustrate this interchangeability and compatibility of hardware, firmware, and software, various illustrative components, blocks, modules, circuits, and steps are generally described according to their functionality. Whether such functions are implemented as hardware, firmware, or software depends on the specific application and the design constraints imposed on the entire system. People familiar with the concepts described herein can implement such functions in an appropriate manner for each specific application, but such implementation decisions should not be interpreted as limiting the scope of the present invention.

[0023] According to some embodiments, the UE transceiver module 230 may be referred to herein as an "uplink" transceiver module 230, which includes RF transmitter and receiver circuits each coupled to an antenna 232. A duplex switch (not shown) may alternatively couple the uplink transmitter or receiver to the uplink antenna in a time duplex manner. Similarly, according to some embodiments, the BS transceiver module 210 may be referred to herein as a "downlink" transceiver module 210, which includes RF transmitter and receiver circuits each coupled to an antenna 212. The downlink duplex switch may alternatively couple the downlink transmitter or receiver to the downlink antenna 212 in a time duplex manner. The operation of the two transceiver modules 210 and 230 is coordinated in time so that while the downlink transmitter is coupled to the downlink antenna 212, the uplink receiver is coupled to the uplink antenna 232 for receiving transmissions over the wireless transmission link 250.

[0024] The UE transceiver module 230 and the BS transceiver module 210 are configured to communicate via a wireless data communication link 250 and cooperate with an appropriately configured RF antenna device 212 / 232 capable of supporting a specific wireless communication protocol and modulation scheme. In some exemplary embodiments, the UE transceiver module 210 and the BS transceiver module 210 are configured to support industry standards such as Long Term Evolution (LTE) and emerging 5G standards. However, it should be understood that the present invention is not necessarily limited to the application of specific standards and related protocols. Instead, the UE transceiver module 230 and the BS transceiver module 210 can be configured to support alternative or additional wireless data communication protocols, including future standards or variations thereof.

[0025] According to various embodiments, for example, BS 202 may be an evolved Node B (eNB), a serving eNB, a target eNB, a femtocell or a microcell. In some embodiments, UE 204 may be embodied in various types of user equipment, such as a mobile phone, a smart phone, a personal digital assistant (PDA), a tablet computer, a laptop computer, a wearable computing device, etc. Processor modules 214 and 236 may be implemented or implemented using a general purpose processor, a content addressable memory, a digital signal processor, an application specific integrated circuit, a field programmable gate array, any suitable programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof, intended to perform the functions described herein. In this way, the processor may be implemented as a microprocessor, a controller, a microcontroller, a state machine, etc. The processor may also be implemented as a combination of computing devices, such as a digital signal processor and a microprocessor, a plurality of microprocessors, one or more microprocessors combined with a digital signal processor core, or any other such configuration.

[0026] In addition, the steps of the methods or algorithms described in conjunction with the embodiments disclosed herein may be directly embodied in hardware, firmware, software modules executed by the processor modules 214 and 236, respectively, or in any practical combination thereof. The memory modules 216 and 234 may be implemented as RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable disk, CD-ROM, or any other form of storage device and / or computer-readable medium known in the art. In this regard, the memory modules 216 and 234 may be coupled to the transceiver modules 210 and 230, respectively, so that the transceiver modules 210 and 230 may read information from and write information to the memory modules 216 and 234, respectively. The memory modules 216 and 234 may also be integrated into their respective transceiver modules 210 and 230. In some embodiments, the memory modules 216 and 234 may each include a cache memory for storing temporary variables or other intermediate information during the execution of instructions executed by the transceiver modules 210 and 230, respectively. Memory modules 216 and 234 may also each include non-volatile memory for storing instructions to be executed by transceiver modules 210 and 230, respectively.

[0027] The network communication module 218 generally represents the hardware, software, firmware, processing logic and / or other components of the base station 202, which can perform two-way communication between the BS transceiver module 210 and other network components and communication nodes configured to communicate with the base station 202. For example, the network communication module 218 can be configured to support Internet or WiMAX traffic. In a typical deployment, but not limited to, the network communication module 218 provides an 802.3 Ethernet interface so that the BS transceiver module 210 can communicate with a computer network based on traditional Ethernet. In this way, the network communication module 218 can include a physical interface for connecting to a computer network (e.g., a mobile switching center (MSC)). As used herein, the terms "configured for", "configured to" and combinations thereof with respect to a specific operation or function refer to a device, component, circuit, structure, machine, signal, etc., which is physically or virtually constructed, programmed, formatted and / or arranged to perform a specific operation or function.

[0028] Compared to multi-carrier systems, single-carrier systems (e.g., discrete Fourier transform OFDM (DFT-S-OFDM) and single-carrier quadrature amplitude modulation (SC_QAM)) can provide relatively better candidate waveforms for high-frequency communications (e.g., communications at higher frequency carrier frequencies). For example, compared to multi-carrier systems, single-carrier systems can have a lower peak-to-average ratio.

[0029] As described above, the phase noise used for higher frequency communications can be relatively larger than the phase noise used for lower frequency communications. Common phase error (CPE) compensation techniques can be used to reduce phase noise. CPE compensation techniques generally include finding an average value of the phase rotation in each OFDM symbol based on a continuous pilot signal or a scattered pilot signal. The average value can be used to compensate for phase noise. CPE compensation techniques can also include monitoring the repetitive data characteristics of a cyclic prefix (CP) to determine the phase deviation of the data for compensating for phase noise. CPE compensation techniques can be used in low frequency communications where the phase noise is relatively low. However, CPE compensation techniques may not be as useful for reducing phase noise in high frequency communications as they are for low frequency communications.

[0030] Therefore, when the carrier frequency is high and the phase noise is large, it may be necessary to consider compensating for the phase noise in each data block or each OFDM symbol. However, since a pilot signal is added in each data block or OFDM symbol, the compensation of the phase noise in each data block or OFDM symbol may result in additional communication overhead. This problem may be more prominent in single-carrier data modulation schemes for wireless communications, which can use higher frequencies but are susceptible to channel fading and low signal-to-noise ratio (SNR).

[0031] Therefore, systems and methods according to various embodiments relate to conjugate data modulation of user data for communication modulated in a manner that reduces phase error. Conjugate data modulation can include modulating user data (e.g., phase shift keying (PSK) modulation) into modulated user data elements, which are interlaced with conjugate data elements (further discussed below). For ease of discussion, these modulated user data elements can be referred to as first data. These user data elements (e.g., first data) can be interlaced with conjugate data elements. For ease of discussion, these conjugate data elements can also be referred to as second data. These conjugate data elements can each be the conjugate or anti-conjugate of different modulated user data elements. In addition, a combination of modulated user data elements (e.g., first data) interlaced with conjugate data elements (e.g., second data) can be referred to as a user data sequence. For ease of discussion, this user data sequence can be referred to as a third data sequence. The user data sequence (e.g., third data sequence) can then be transmitted to a receiver. In some embodiments, to create a fourth data sequence, the user data sequence may be concatenated with a preceding first pilot sequence (e.g., the earliest transmitted data element of the user data sequence) and a following second pilot sequence (e.g., the last transmitted data element of the user data sequence). The first pilot sequence and the second pilot sequence may be a predetermined set or collection of data elements known to the receiver before demodulating the first pilot sequence and / or the second pilot sequence. For ease of discussion, the first pilot sequence may be referred to as a first sequence or S1. In addition, for ease of description, the second pilot sequence may be referred to as a second sequence or S2.

[0032] Therefore, in some embodiments, a conjugate data element (e.g., second data) may be inserted between data elements of a user data element (e.g., first data) to obtain a user data sequence (e.g., third data sequence). In the user data sequence (e.g., third data sequence), each data element of the second data is conjugated or anti-conjugated with an adjacent user data element (e.g., first data). In addition, a first pilot sequence (e.g., S1) and a second pilot sequence (e.g., S2) may be inserted before and after the user data sequence (e.g., third data sequence), respectively, to obtain a fourth data sequence that may be transmitted to a receiver. The first pilot sequence (e.g., S1) and the second pilot sequence (e.g., S2) may be reference sequences, i.e., sequences known to a receiving end (e.g., receiver).

[0033] In some embodiments, the user data sequence (e.g., the third data sequence) includes an equal number of modulated user data elements and conjugate data elements (e.g., the second data). In other words, the user data sequence (e.g., the first data) is equal to the conjugate data element (e.g., the second data) in length, so that each user data element (e.g., the first data) is adjacent to the corresponding conjugate data element (e.g., the second data).

[0034] In some embodiments, the user data sequence (e.g., the third data sequence) includes modulated user data elements (e.g., first data) interleaved with conjugate data elements (e.g., second data) at uniform intervals. In other words, the conjugate data elements (e.g., second data) can be uniformly inserted between the modulated user data elements (e.g., first data). That is, in the user data sequence (e.g., the third data sequence), adjacent data intervals of the conjugate data elements (e.g., second data) are the same.

[0035] In certain embodiments, the user data sequence (eg, the third data sequence) includes modulated user data elements (eg, the first data) interleaved with conjugate data elements (eg, the second data) at predetermined time domain positions. For example, each modulated user data element (e.g., first data) may be followed by a corresponding conjugated data element (e.g., second data), each conjugated data element (e.g., second data) may be followed by a corresponding user data element (e.g., first data), each second modulated user data element (e.g., first data) may be followed by a corresponding conjugated data element (e.g., second data), each conjugated data element (e.g., second data) may be followed by a corresponding one of each second modulated user data element (e.g., first data), each third modulated user data element (e.g., first data) may be followed by a corresponding one of the conjugated data elements (e.g., second data), each conjugated data element (e.g., second data) may be followed by a corresponding one of each third modulated user data element (e.g., first data), each fourth modulated user data element (e.g., first data) may be followed by a corresponding one of the conjugated data elements (e.g., second data), each conjugated data element (e.g., second data) may be followed by a corresponding one of each fourth modulated user data element (e.g., first data), and so on. In other words, the conjugate data element (e.g., the second data) is inserted between the modulated user data elements (e.g., the first data) at the predefined time domain position. For example, the predefined position may be: inserted at the position 2n, 3n, or 4n in the time domain, where n is a positive integer. When the predefined position is 2n, one conjugate data element (e.g., the second data) is inserted into each modulated user data element (e.g., the first data); when the predefined position is 3n, one conjugate data element (e.g., the second data) is inserted into every two modulated user data elements (e.g., the first data); when the predefined position is 4n, one conjugate data element (e.g., the second data) is inserted into every three modulated user data elements (e.g., the first data). Although some embodiments describe how the conjugate data element (e.g., the second data) may be immediately followed (e.g., later in the time domain) and adjacent to the corresponding modulated user data element (e.g., the first data) of the conjugate pair, in various embodiments, any order of the conjugate pairs may be utilized as needed for different applications. For example, other embodiments may have the modulated user data element (eg, first data) immediately following (eg, later in the time domain) and adjacent to the corresponding conjugate data element (eg, second data) of the conjugate pair.

[0036] In some embodiments, the combination of the pre-pilot sequence (e.g., S1), the user data sequence (e.g., the third data sequence), and the post-pilot sequence (e.g., S2) is a predetermined number of data elements. In other words, the fourth data sequence has a constant length. For example, the combination of the pre-pilot sequence (e.g., S1), the user data sequence (e.g., the third data sequence), and the post-pilot sequence (e.g., S2) can occupy a single Fourier window (e.g., the window length of the subsequent FFT processing).

[0037] In some embodiments, the leading pilot sequence starts at the beginning of a single Fourier window, and the trailing pilot sequence ends at the end of the single Fourier window. In other words, the starting and ending positions of the fourth data sequence can be the starting and ending positions of the subsequent FFT processing. In addition, the starting and stopping positions of the subsequent FFT processing can be at the beginning of the leading pilot sequence (e.g., S1) and the end of the trailing pilot sequence (e.g., S2), respectively.

[0038] In some embodiments, when the length of the previous pilot sequence (e.g., S1) or the next pilot sequence (e.g., S2) changes, the length of the conjugate data element (e.g., the second data) may also change, while the length of the modulated user data element (e.g., the first data) may remain constant. Alternatively, when the length of the modulated user data element (e.g., the first data) or the conjugate data element (e.g., the second data) changes, the previous pilot sequence (e.g., S1) or the next pilot sequence (e.g., S2) may also change.

[0039] In some embodiments, the user data sequence is transmitted after filtering and converting from a digital signal to an analog signal. For example, transmitting a fourth data sequence (e.g., a combination of a leading pilot sequence (e.g., S1), a user data sequence (e.g., a third data sequence), and a trailing pilot sequence (e.g., S2)) also includes performing FFT processing on the fourth data sequence, and then performing subcarrier mapping, and then performing inverse fast Fourier transform (IFFT) processing. This can result in the transmission of a fifth data sequence via IFFT. In various embodiments, FFT processing can broadly refer to discrete Fourier transform (DFT) processing, and IFFT processing includes the concept of inverse discrete Fourier transform (IDFT) processing. In a specific embodiment, transmitting the fourth data sequence can include filtering and digital-to-analog conversion of the fourth data sequence, and then transmitting the digital-to-analog converted signal (e.g., without FFT and IFFT processing).

[0040] In some embodiments, control information may be transmitted. The control information may include a time domain position associated with a conjugate data element (e.g., second data) to a receiver (recipient) of a user data sequence (e.g., a third data sequence). The control information may be in a control information format, wherein the control information may be used to indicate a position of a conjugate data element (e.g., second data) predefined in the time domain. In various embodiments, the control information format may be a control information format transmitted by a downlink or uplink control channel. In a further embodiment, the control information may be transmitted as part of a control channel or radio resource control (RRC) signaling (e.g., in a control information format for downlink or uplink RRC signaling transmission).

[0041] As described above, the conjugation of the reference conjugated data element (e.g., the second data) with the modulated user data (e.g., the first data) may refer to conjugation or negative conjugation. Therefore, in the user data sequence (e.g., the third data sequence), each data element of the conjugated data element (e.g., the second data) is conjugated or anti-conjugated with an adjacent modulated user data (e.g., the first data), which has the advantage of reducing phase noise in receiver processing. For example, the phase noise of adjacent data elements in the time domain may be approximately equal, so the phase noise may be estimated based on the joint processing of adjacent data elements forming a conjugated or anti-conjugated conjugated pair. In addition, since the data elements are conjugated or anti-conjugated with each other, joint demodulation may be performed to improve the received signal-to-noise ratio.

[0042] In some embodiments, the number of conjugate data elements (e.g., second data) may be equal to the modulated user data (e.g., first data). This may improve the density of phase noise estimation in the time domain (e.g., due to the introduction of conjugate pairs for each modulated user data (e.g., first data)). In addition, the user data sequence (e.g., third data sequence) may then be directly demodulated by joint processing without first estimating the phase noise of each data element insertion position. This may be because the positions of the modulated user data elements and the conjugate data elements are predetermined or known to the transmitter and the receiver.

[0043] In a particular embodiment, it may be advantageous to connect a user data sequence (e.g., the third data sequence) with a leading pilot sequence (e.g., S1) at one end (e.g., the front end) and a trailing pilot sequence (e.g., S2) at the other end (e.g., the back end). For example, this will allow estimating CPE compensation in the entire symbol based on a pilot signal including the leading pilot sequence (e.g., S1) and the trailing pilot sequence (e.g., S2). More specifically, once the CPE is estimated, the CPE can be compensated (e.g., removed) from the fourth data sequence during demodulation.

[0044] In a further embodiment, it may be advantageous to insert a conjugate data element (e.g., second data) into a modulated user data element (e.g., first data) at a predefined time domain position. For example, these time domain positions may represent an embodiment in which not every modulated user data element (e.g., first data) is adjacent to a corresponding conjugate data element (e.g., second data). Since fewer time domain resources are required for conjugate data elements (e.g., second data), this arrangement can increase the user data throughput of the same number of all time domain resources. In addition, when the phase noise within a data block or within an OFDM symbol does not vary much, the insertion of the conjugate data element (e.g., second data) at a predefined time domain position may be performed. Therefore, in the case where it is known that the phase noise is relatively small (e.g., based on the degree of variation of the actual phase noise, and the position density of the estimated phase noise is appropriately reduced, thereby improving the spectrum efficiency) and / or in the case where a greater user data throughput is required, the insertion of the conjugate data element (e.g., second data) at a predefined time domain position may be selectively used.

[0045] As described above, in some embodiments, the length of the fourth data sequence may be the length of the Fourier transform window of the subsequent FFT processing. This may simplify demodulation because the subcarrier spacing in the frequency domain may remain unchanged and the orthogonality of frequency division multiplexing may be more easily achieved.

[0046] In a specific embodiment, the control information can be transmitted to the receiver in a control information format, wherein the indication information can be used to indicate a predetermined position of a conjugate data element (e.g., second data) in the time domain. Therefore, the time domain position of the conjugate data element (e.g., second data) and the length of the leading pilot sequence (e.g., S1) and the trailing pilot sequence (e.g., S2) can be adjusted in real time according to the amplitude of the delay and phase noise, thereby improving the system's ability to resist phase noise and multipath delay. This can also improve spectrum utilization, because the receiver of the fourth data sequence can use the control information to more easily demodulate the fourth data sequence.

[0047] Figure 3 3 is a conceptual block diagram 300 of a fourth data sequence 302 in the time domain according to some embodiments. The fourth data sequence 302 may include a user data sequence 304 (e.g., a third data sequence) connected with a preamble sequence 306 (e.g., S1) at one end (e.g., a front end with an earlier time domain position) and a postamble sequence 308 (e.g., S2) at the other end (e.g., a back end with a later time domain position). In addition, the user data sequence 304 (e.g., the third data sequence) may include a modulated user data element 310 (e.g., a first data) interleaved with a conjugate data element 312 (e.g., a second data). In addition, the size of the fourth data sequence 302 may be equivalent to a single data block 318.

[0048] More specifically, interleaving may cause each modulated user data element 310 (e.g., first data) to be adjacent to a corresponding conjugate data element 312 (e.g., second data) so as to form a conjugate pair 314 between adjacent modulated user data elements 310 (e.g., first data) and corresponding conjugate data elements 312 (e.g., second data). As described above, the conjugate data element 312 (e.g., second data) may be a conjugate or negative conjugate of the corresponding modulated user data element 310 (e.g., first data). For example, assuming that the modulated user data element 310 (e.g., first data) is: [1+i, 1-i, -1+i, -1-i, ..., -1+i, 1+i]. Assuming that the conjugate data element 312 (e.g., the second data) is uniformly inserted into the modulated user data element 310 (e.g., the first data), the second data sequence as the conjugate of the corresponding modulated user data element 310 (e.g., the first data) is: [1-i, 1+i, -1-i, -1+i, ..., -1-i, 1-i]. Then, after interleaving, the obtained user data sequence 304 (e.g., the third data sequence) can be: [1+i, 1-i, 1-i, 1+i, -1+i, -1-i, -1-i, -1+i ..., -1+i, -1-i, 1+i, 1-i]. In addition, assuming that the conjugate data elements 312 (e.g., the second data) are inserted into the modulated user data elements 310 (e.g., the first data) in odd numbers, then, after interleaving, the obtained user data sequence 304 (e.g., the third data sequence) can be: [1-i, 1+i, 1+i, 1-i, -1-i, -1+i, -1+i, -1-i..., -1-i, -1+i, 1-i, 1+i].

[0049] In some embodiments, the number of modulated user data elements 310 (e.g., first data) and conjugate data elements 312 (e.g., second data) may be the same (e.g., they may have the same length). In other words, the conjugate data elements 312 (e.g., second data) may be inserted into the modulated user data elements 310 (e.g., first data) evenly or oddly. That is, in the user data sequence 304 (e.g., third data sequence) obtained after insertion, the adjacent data intervals of the conjugate data elements 312 (e.g., second data) are the same. Inserting the leading pilot sequence 306 (e.g., S1) at one end (e.g., the front end with an earlier time domain position) and inserting the trailing pilot sequence 308 (e.g., S2) at the other end (e.g., the trailing end with a later time domain position) may generate the fourth data sequence 302. In some embodiments, the lengths of the leading pilot sequence 306 (e.g., S1) and the trailing pilot sequence 308 (e.g., S2) may be the same or different, depending on the multipath nature of the wireless channel. In further embodiments, the length adjustment may be such that the lengths of the leading pilot sequence 306 (eg, S1) and the trailing pilot sequence 308 (eg, S2) are the same. In various embodiments, the size of the fourth data sequence 302 may be equivalent to a single data block 318.

[0050] In a particular embodiment, the conjugate data element 312 (e.g., the second data) may have a predefined position in the time domain of 2n, where n is a positive integer. In other words, the conjugate data element 312 (e.g., the second data) may be at an even position of the user data sequence 304 (e.g., the third data sequence). The control information may be indicated from the transmitter of the fourth data sequence to the receiver of the fourth data sequence via a control information format (e.g., Info-1).

[0051] Figure 4 is a conceptual block diagram 400 of a fourth data sequence 402 in the time domain according to some embodiments. Figure 4 Examples and Figure 3 The difference of the embodiment is that Figure 4 A fourth data sequence equivalent to a single Fourier window (eg, the window length used for FFT processing) is shown.

[0052] The fourth data sequence 402 may include a user data sequence 404 (e.g., a third data sequence) connected to a pre-pilot sequence 406 (e.g., S1) at one end (e.g., a front end with an earlier time domain position) and a post-pilot sequence 408 (e.g., S2) at the other end (e.g., a rear end with a later time domain position). In addition, the user data sequence 404 (e.g., a third data sequence) may include a modulated user data element 410 (e.g., first data) interleaved with a conjugate data element 412 (e.g., second data). In addition, the size of the fourth data sequence 402 may be equivalent to a single Fourier window 418 (e.g., a window length for FFT processing).

[0053] More specifically, interleaving may cause each modulated user data element 410 (e.g., first data) to be adjacent to a corresponding conjugate data element 412 (e.g., second data) so as to form a conjugate pair 414 between adjacent modulated user data elements 410 (e.g., first data) and corresponding conjugate data elements 412 (e.g., second data). As described above, the conjugate data element 412 (e.g., second data) may be a conjugate or negative conjugate of the corresponding modulated user data element 410 (e.g., first data). For example, assuming that the modulated user data element 410 (e.g., first data) is: [1+i, 1-i, -1+i, -1-i, ..., -1+i, 1+i]. Assuming that the conjugate data element 412 (e.g., the second data) is uniformly inserted into the modulated user data element 410 (e.g., the first data), the second data sequence as the conjugate of the corresponding modulated user data element 410 (e.g., the first data) is: [1-i, 1+i, -1-i, -1+i, ..., -1-i, 1-i]. Then, after interleaving, the obtained user data sequence 404 (e.g., the third data sequence) can be: [1+i, 1-i, 1-i, 1+i, -1-i, -1+i, ..., -1+i, -1-i, 1+i, 1-i]. In addition, assuming that the conjugate data elements 312 (e.g., the second data) are inserted into the modulated user data elements 410 (e.g., the first data) in odd numbers, then, after interleaving, the obtained user data sequence 404 (e.g., the third data sequence) can be: [1-i, 1+i, 1+i, 1-i, -1-i, -1+i, -1+i, -1-i, ..., -1-i, -1+i, 1-i, 1+i].

[0054] In some embodiments, the number of modulated user data elements 410 (e.g., first data) and conjugate data elements 412 (e.g., second data) may be the same (e.g., they may have the same length). In other words, the conjugate data elements 412 (e.g., second data) may be inserted into the modulated user data elements 410 (e.g., first data) uniformly or oddly. That is, in the user data sequence 404 (e.g., third data sequence) obtained after insertion, the adjacent data intervals of the conjugate data elements 412 (e.g., second data) are the same. Inserting the leading pilot sequence 406 (e.g., S1) at one end (e.g., the front end with an earlier time domain position) and inserting the trailing pilot sequence 408 (e.g., S2) at the other end (e.g., the trailing end with a later time domain position) may generate a fourth data sequence. In some embodiments, the lengths of the leading pilot sequence 406 (e.g., S1) and the trailing pilot sequence 408 (e.g., S2) may be the same or different, depending on the multipath nature of the wireless channel. In a further embodiment, the length adjustment may be such that the lengths of the leading pilot sequence 406 (e.g., S1) and the trailing pilot sequence 408 (e.g., S2) are the same. In various embodiments, the size of the fourth data sequence 402 may be equivalent to a single Fourier window 418 (e.g., the window length used for FFT processing).

[0055] In a particular embodiment, the conjugate data element 412 (e.g., the second data) may have a predefined position in the time domain of 2n, where n is a positive integer. In other words, the conjugate data element 412 (e.g., the second data) may be at an even position of the user data sequence 404 (e.g., the third data sequence). The control information may be indicated from the transmitter of the fourth data sequence to the receiver of the fourth data sequence via a control information format (e.g., Info-1).

[0056] Figure 5 5 is a conceptual block diagram 500 of a fourth data sequence 502 having a relatively long pilot sequence in the time domain according to some embodiments. The fourth data sequence 502 may include a user data sequence 504 (e.g., a third data sequence) connected with a leading pilot sequence 506 (e.g., S1) at one end (e.g., a front end with an earlier time domain position) and a trailing pilot sequence 508 (e.g., S2) at the other end (e.g., a trailing end with a later time domain position). In addition, the user data sequence 504 (e.g., a third data sequence) may include a modulated user data element 510 (e.g., a first data) interleaved with a conjugate data element 512 (e.g., a second data).

[0057] More specifically, interleaving may cause each second modulated user data element 510 (e.g., first data) to be adjacent to a corresponding conjugate data element 512 (e.g., second data) so as to form a conjugate pair 514 between each second modulated user data element 510 (e.g., first data) and the corresponding conjugate data element 512 (e.g., second data). In other words, at least one modulated user data element 510 (e.g., first data) may be connected to another modulated user data element 510 (e.g., first data) and to a conjugate data element 512 (e.g., second data) as a conjugate pair. As described above, the conjugate data element 512 (e.g., second data) may be a conjugate or negative conjugate of the corresponding modulated user data element 510 (e.g., first data). In addition, the size of the fourth data sequence 502 may be equivalent to a single Fourier window 518 (e.g., a window length for FFT processing).

[0058] In some embodiments, the number of modulated user data elements 510 (e.g., first data) may be twice the number of conjugate data elements 512 (e.g., second data). In other words, in the user data sequence 504 (e.g., third data sequence) obtained after insertion, adjacent data intervals of the conjugate data elements 512 (e.g., second data) are the same. Inserting the leading pilot sequence 506 (e.g., S1) at one end (e.g., the front end with an earlier time domain position) and inserting the trailing pilot sequence 508 (e.g., S2) at the other end (e.g., the trailing end with a later time domain position) may generate a fourth data sequence 502. In some embodiments, the lengths of the leading pilot sequence 506 (e.g., S1) and the trailing pilot sequence 508 (e.g., S2) may be the same or different, depending on the multipath nature of the wireless channel. In a further embodiment, the length adjustment may make the lengths of the leading pilot sequence 506 (e.g., S1) and the trailing pilot sequence 508 (e.g., S2) the same. In various embodiments, the size of the fourth data sequence 502 may be equivalent to a single Fourier window 518 (eg, a window length used for FFT processing).

[0059] like Figure 5 As shown, the number and / or length of the modulated user data elements 510 (e.g., the first data) may be greater than the number and / or length of the conjugate data elements 512 (e.g., the second data). In addition, the leading pilot sequence 506 (e.g., S1) and the trailing pilot sequence 508 (e.g., S2) may be such as Figure 4 The shown is relatively long (assuming the same FFT window length or fourth data sequence length). Therefore, Figure 5The fourth data sequence 502 may reflect the situation that the multipath delay is large and the phase noise changes slowly in the time domain (there is no change every three sampling points (e.g., three data elements)). In addition, the length of the fourth data sequence 502 may be the length of a single Fourier window 518 (e.g., the window length used for FFT processing). Therefore, the start and end positions of the fourth data sequence 502 may be the start and end positions of a single Fourier window 518 (e.g., the window length used for FFT processing).

[0060] In a particular embodiment, the conjugate data element 512 (e.g., the second data) may have a predefined position in the time domain of 3n, where n is a positive integer. Therefore, the conjugate data element 512 (e.g., the second data) may be at every third position of the user data sequence 504 (e.g., the third data sequence). The control information may indicate the control information from the transmitter of the fourth data sequence to the receiver of the fourth data sequence via a control information format (e.g., Info-2 or Info-3).

[0061] Figure 6 6 is a conceptual block diagram 600 of a fourth data sequence 602 having a relatively short pilot sequence with greater user data throughput in the time domain according to some embodiments. The fourth data sequence 602 may include a user data sequence 604 (e.g., a third data sequence) connected with a leading pilot sequence 606 (e.g., S1) at one end (e.g., a front end with an earlier time domain position) and a trailing pilot sequence 608 (e.g., S2) at the other end (e.g., a front end with a later time domain position). In addition, the user data sequence 604 (e.g., the third data sequence) may include a modulated user data element 610 (e.g., a first data) interleaved with a conjugate data element 612 (e.g., a second data).

[0062] More specifically, interleaving may cause each second modulated user data element 610 (e.g., first data) to be adjacent to a corresponding conjugate data element 612 (e.g., second data), so that a conjugate pair 614 is formed between each second modulated user data element 610 (e.g., first data) and a corresponding conjugate data element 612 (e.g., second data). Thus, at least one modulated user data element 610 (e.g., first data) may be connected to another modulated user data element 610 (e.g., first data) and to a conjugate data element 612 (e.g., second data) as its conjugate pair. As described above, the conjugate data element 612 (e.g., second data) may be a conjugate or negative conjugate of the corresponding modulated user data element 610 (e.g., first data). In addition, the size of the fourth data sequence 602 may be equivalent to a single Fourier window 618 (e.g., a window length for FFT processing).

[0063] In some embodiments, the number of modulated user data elements 610 (e.g., first data) may be twice the number of conjugate data elements 612 (e.g., second data). In other words, in the user data sequence 604 (e.g., third data sequence) obtained after insertion, the adjacent data intervals of the conjugate data elements 612 (e.g., second data) are the same. Inserting the leading pilot sequence 606 (e.g., S1) at one end (e.g., the front end with an earlier time domain position) and inserting the trailing pilot sequence 608 (e.g., S2) at the other end (e.g., the trailing end with a later time domain position) may generate a fourth data sequence. In some embodiments, the lengths of the leading pilot sequence 606 (e.g., S1) and the trailing pilot sequence 608 (e.g., S2) may be the same or different, depending on the multipath nature of the wireless channel. In a further embodiment, the length adjustment may make the lengths of the leading pilot sequence 606 (e.g., S1) and the trailing pilot sequence 608 (e.g., S2) the same. In various embodiments, the size of the fourth data sequence 602 may be equivalent to a single Fourier window 618 (eg, a window length used for FFT processing).

[0064] like Figure 6 As shown, the number and / or length of the modulated user data elements 610 (e.g., the first data) may be greater than the number and / or length of the conjugate data elements 612 (e.g., the second data). In addition, the leading pilot sequence 606 (e.g., S1) and the trailing pilot sequence 608 (e.g., S2) may be relatively smaller than the example shown in FIG. Figure 5 Assume that the fourth data sequence 602 is in Figure 5 and Figure 6 is constant between Figure 6 An embodiment having a greater user data throughput per unit time may be reflected. Figure 6 The fourth data sequence 602 may reflect a situation where the multipath delay is small and the phase noise changes slowly in the time domain (e.g., there is no change every three sampling points). The length of the fourth data sequence 602 may be the length of a single Fourier window 618 (e.g., the window length used for FFT processing). In other words, the start and end positions of the fourth data sequence 602 may be the start and end positions of a single Fourier window 618 (e.g., the window length used for FFT processing).

[0065] In a particular embodiment, the conjugate data element 612 (e.g., the second data) may have a predefined position in the time domain of 3n, where n is a positive integer. In other words, the conjugate data element 612 (e.g., the second data) may be at every third position of the user data sequence 604 (e.g., the third data sequence). The control information may be indicated from the transmitter of the fourth data sequence to the receiver of the fourth data sequence via a control information format (e.g., Info-2 or Info-3).

[0066] Although various embodiments of the present invention have been described above, it should be understood that they are presented only in an exemplary and not limiting manner. Similarly, various figures may depict example architectures or configurations, which are provided so that those of ordinary skill in the art can understand the exemplary features and functions of the present invention. However, such personnel will understand that the present invention is not limited to the example architectures or configurations shown, but can use a variety of alternative architectures and configurations to implement the present invention. In addition, as those of ordinary skill in the art will understand, one or more features of an embodiment may be combined with one or more features of another embodiment described herein. Therefore, the breadth and scope of the present disclosure should not be limited by any of the above-described exemplary embodiments.

[0067] It should also be understood that any reference to an element or embodiment using names such as "first," "second," etc., herein does not generally limit the number or order of those elements. Rather, these names may be used herein as a convenient means of distinguishing between two or more elements or examples of elements. Thus, reference to a first and a second element does not mean that only two elements may be used, or that the first element must be located before the second element in some manner.

[0068] In addition, those of ordinary skill in the art will appreciate that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, and symbols such as those referenced in the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0069] It will be further understood by those of ordinary skill in the art that any of the various schematic logic blocks, modules, processors, devices, circuits, methods, and functions described in conjunction with the aspects disclosed herein may be implemented by electronic hardware (e.g., digital implementations, analog implementations, or a combination of the two), firmware, various forms of design code or programs containing instructions (for convenience, may be referred to herein as "software" or "software modules"), or any combination of these technologies. In order to clearly illustrate this interchangeability of hardware, firmware, and software, various schematic components, blocks, modules, circuits, and steps have been described above generally according to their functions. Whether such functionality is implemented as hardware, firmware, or software, or a combination of these technologies, depends on the specific application and the design constraints imposed on the overall system. Technicians may implement the described functionality in various ways for each specific application, but such implementation decisions cannot cause a departure from the scope of the present disclosure.

[0070] In addition, it will be understood by those of ordinary skill in the art that the various illustrative logic blocks, modules, devices, components, and circuits described herein may be implemented within or performed by an integrated circuit (IC), which may include: a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic device, or any combination thereof. The logic blocks, modules, and circuits may further include antennas and / or transceivers to communicate with various components within a network or within a device. A general purpose processor may be a microprocessor, but alternatively, the processor may be any conventional processor, controller, or state machine. The processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors combined with a DSP core, or any other suitable configuration to perform the functions described herein.

[0071] If the function is implemented in software, the function can be stored as one or more instructions or codes on a computer-readable medium. Therefore, the steps of the method or algorithm disclosed herein can be implemented as software stored on a computer-readable medium. Computer-readable media include both computer storage media and communication media, and communication media include any media that can enable a computer program or code to be transferred from one place to another. The storage medium can be any available medium that a computer can access. By way of example and in a non-limiting manner, such a computer-readable medium may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage devices, magnetic disk storage devices or other magnetic storage devices, or any other medium that can be used to store desired program codes in the form of instructions or data structures and can be accessed by a computer.

[0072] In this document, the term "module" as used herein refers to software, firmware, hardware, and any combination of these elements for performing the associated functions described herein. In addition, for the purpose of discussion, various modules are described as discrete modules; however, it is obvious to those of ordinary skill in the art that two or more modules can be combined to form a single module that performs the associated functions according to embodiments of the present invention.

[0073] In addition, one or more functions described in this document may be performed with the aid of computer program code stored in a "computer program product," "computer-readable medium," or the like, which are used herein to generally refer to media such as memory storage devices or storage units. These and other forms of computer-readable media may involve storing one or more instructions for use by a processor to cause the processor to perform specific operations. Such instructions are often referred to as "computer program code" (which may be grouped in the form of a computer program or other grouping), which, when executed, enable a computing system to perform the desired operations.

[0074] In addition, memory or other storage devices and communication components can be used in embodiments of the present invention.It should be understood that, for the sake of clarity, the above description has described embodiments of the present invention with reference to different functional units and processors.However, it will be apparent that any appropriate functional distribution between different functional units, processing logic elements or domains can be used without departing from the present invention.For example, the function illustrated as being performed by a separate processing logic element or controller can be performed by the same processing logic element or controller.Therefore, reference to a specific functional unit is only a reference to an appropriate device for providing the described function, rather than indicating a strict logical or physical structure or organization.

[0075] Various modifications to the embodiments described in this disclosure will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the scope of this disclosure. Therefore, this disclosure is not intended to be limited to the embodiments shown herein, but is to be given the widest scope consistent with the novel features and principles disclosed herein, as set forth in the claims below.

Claims

1. A wireless communication method performed by a device, comprising: modulating user data into modulated user data elements; determining conjugate data elements, wherein each conjugate data element is a conjugate or anti-conjugate of a corresponding one of the modulated user data elements; and A preamble sequence is transmitted in the time domain, the preamble sequence is followed by a user data sequence including modulated user data elements interleaved with the conjugate data elements, and a postamble sequence is transmitted after the user data sequence is transmitted, wherein the preamble sequence and the postamble sequence are predetermined data element sets.

2. The method according to claim 1, wherein: A combination of the preamble sequence, the user data sequence, and the postamble sequence is a predetermined number of data elements.

3. The method according to claim 1, wherein: A combination of the preamble sequence, the user data sequence, and the postamble sequence occupies a single Fourier window.

4. The method according to claim 3, wherein: The leading pilot sequence starts at the beginning of the single Fourier window and the trailing pilot sequence ends at the end of the single Fourier window.

5. The method according to claim 1, further comprising: The user data sequence is transmitted after being processed by Fourier transform.

6. The method according to claim 1, further comprising: The user data sequence is filtered and converted from a digital signal to an analog signal before transmission.

7. A wireless communication method performed by a device, comprising: receiving a pre-pilot sequence followed by a user data sequence, and receiving a post-pilot sequence followed by the user data sequence, wherein the user data sequence comprises modulated user data elements interleaved with conjugate data elements, wherein the conjugate data elements are each a conjugate or a negative conjugate of a different modulated user data element, and wherein the pre-pilot sequence and the post-pilot sequence are predetermined sets of data elements; and The user data sequence is demodulated to generate user data.

8. The method according to claim 7, further comprising: determining a phase error estimate based on a pilot signal including the leading pilot sequence and the trailing pilot sequence; as well as The user data sequence is demodulated based on compensation for the phase error estimate.

9. The method according to claim 7, wherein: The user data sequence includes an equal number of modulated user data elements and conjugate data elements.

10. The method according to claim 7, wherein: The user data sequence includes modulated user data elements interleaved with the conjugate data elements at uniform intervals.

11. The method according to claim 7, wherein: The user data sequence includes modulated user data elements interleaved with the conjugate data elements at predetermined time domain positions.

12. The method according to claim 7, wherein: The user data sequence includes at least one of the following: each modulated user data element followed by a corresponding one of said conjugated data elements, each conjugated data element is followed by a corresponding one of said modulated user data elements, each second modulated user data element is followed by a corresponding one of said conjugated data elements, each conjugated data element followed by a corresponding one of each second modulated user data elements, each third modulated user data element is followed by a corresponding one of said conjugated data elements, each conjugated data element followed by a corresponding one of each third modulated user data elements, each fourth modulated user data element is followed by a corresponding one of said conjugated data elements, and Each conjugated data element is followed by a corresponding one of each fourth modulated user data elements.

13. The method according to claim 7, wherein: The leading pilot sequence and the trailing pilot sequence are demodulated for a common phase error compensation technique.

14. The method according to claim 7, further comprising: Control information is received, which includes a time domain position associated with the conjugated data element to a receiver of the user data sequence.

15. The method according to claim 14, further comprising: Control information is received as part of a control channel or radio resource control (RRC) signaling.

16. A non-transitory computer readable medium having stored thereon computer executable instructions for performing the method according to any one of claims 1 to 15.

17. A wireless communication device, comprising: The processor is configured as: modulating the user data into modulated user data elements, determining conjugate data elements, wherein each conjugate data element is a conjugate or anti-conjugate of a corresponding one of the modulated user data elements, and The transmitter is configured as: A preamble sequence is transmitted in the time domain, the preamble sequence is followed by a user data sequence including modulated user data elements interleaved with the conjugate data elements, and a postamble sequence is transmitted after the user data sequence is transmitted, wherein the preamble sequence and the postamble sequence are predetermined data element sets.

18. The apparatus according to claim 17, wherein: A combination of the preamble sequence, the user data sequence, and the postamble sequence is a predetermined number of data elements.

19. A wireless communication device, comprising: The receiver is configured as: receiving a pre-pilot sequence followed by a user data sequence, and receiving a post-pilot sequence followed by the user data sequence, wherein the user data sequence comprises modulated user data elements interleaved with conjugate data elements, wherein the conjugate data elements are each a conjugate or anti-conjugate of a different modulated user data element, and wherein the pre-pilot sequence and the post-pilot sequence are predetermined sets of data elements; and The processor is configured as: The user data sequence is demodulated to generate user data.

20. The apparatus of claim 19, wherein: The processor is further configured to: determining a phase error estimate based on the leading pilot sequence and the trailing pilot sequence, and The user data sequence is demodulated based on compensation for the phase error estimate.

21. The apparatus of claim 19, wherein: The user data sequence includes an equal number of modulated user data elements and conjugate data elements.

22. The apparatus of claim 19, wherein: The user data sequence includes modulated user data elements interleaved with the conjugate data elements at uniform intervals.

23. The apparatus of claim 19, wherein: The user data sequence includes modulated user data elements interleaved with the conjugate data elements at predetermined time domain positions.

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