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EP-4091274-B1 - TRANSMITTING DEVICE, RECEIVING DEVICE, AND METHODS FOR RANDOM-ACCESS COMMUNICATION

EP4091274B1EP 4091274 B1EP4091274 B1EP 4091274B1EP-4091274-B1

Inventors

  • GUILLAUD, MAXIME
  • DECURNINGE, Alexis

Dates

Publication Date
20260506
Application Date
20200305

Claims (14)

  1. A transmitting device (102) for a random-access communication, comprising: an encoder (208) that is configured to: acquire an input message having a sequence of bits; form a plurality of blocks from the sequence of bits; and determine a plurality of vectors for the plurality of blocks; a mapper circuit (210) that is configured to construct a symbol vector based on the plurality of vectors, wherein the symbol vector is constructed by combining the plurality of vectors with each other through a Kronecker product, wherein the plurality of vectors correspond to a plurality of sub-constellations and the symbol vector corresponds to a constellation, and wherein the constellation is a cartesian product of the plurality of sub-constellations, and wherein a product of a vector size of each of the plurality of vectors is equal to a number of channel uses; and an antenna (206) that is configured to transmit the constructed symbol vector over a radio frequency, RF, signal to a receiving device (104), wherein the constructed symbol vector represents a symbol modulated in the radio frequency signal.
  2. The transmitting device (102) according to claim 1, wherein the encoder (208) is further configured to encode the sequence of bits by use of a channel code that adds redundancy to the sequence of bits to obtain a sequence of coded bits, wherein the plurality of blocks are formed from the sequence of coded bits when the sequence of bits are encoded by the channel code.
  3. The transmitting device (102) according to claim 1 or 2, wherein each of the plurality of sub-constellations has a structure selected from at least one of: a Grassmannian constellation, a cube-split constellation, a canonical basis, a single-element codebook or a constellation wherein each of the plurality of vectors is divided to a pilot part and a data part.
  4. The transmitting device (102) according to any one of the preceding claims, wherein the symbol vector has at least one of a rank 1 tensor structure, a rank-n tensor structure or a rank-K tensor structure, and wherein the mapper circuit (210) is further configured to determine a one-to-one correspondence between each element of the tensor structure of the symbol vector having two or more modes and a corresponding signal frequency in order to modulate the symbol vector in the radio frequency signal.
  5. A receiving device (104) for a random-access communication, comprising: at least one antenna (402) configured to receive a plurality of radio frequency signals concurrently from a plurality of transmitting devices (108); an equalizer circuit (410) that is configured to estimate a plurality of symbol vectors from the received plurality of radio frequency signals in digital domain, and segregate the plurality of symbol vectors, wherein a symbol vector is constructed by combining a plurality of vectors with each other through a Kronecker product, wherein the plurality of vectors corresponds to a plurality of sub-constellations and the symbol vector corresponds to a constellation, and wherein the constellation is a cartesian product of the plurality of sub-constellations, and wherein a product of a vector size of each of the plurality of vectors is equal to a number of channel uses; and a plurality of decoders (412), wherein each decoder is configured to decode one segregated symbol vector of the estimated plurality of symbol vectors to obtain a plurality of decoded messages, wherein each decoded message has a sequence of bits that corresponds to data associated with a corresponding transmitting device of the plurality of transmitting devices (108).
  6. The receiving device (104) according to claim 5, wherein the equalizer circuit (410) is a non-coherent equalizer in which a channel state information is unknown when the plurality of symbol vectors is estimated.
  7. The receiving device (104) according to claim 5 or 6, wherein the equalizer circuit (410) is configured to execute a first type of decoding in which the equalizer circuit (410) is configured to: utilize a first parameter (434) that represents a maximum possible number of the plurality of decoded messages to estimate a number of active transmitting devices; and execute the first type of decoding based on a maximum likelihood decoding or a canonical polyadic decomposition.
  8. The receiving device (104) according to claim 7, wherein the equalizer circuit (410) is further configured to utilize a second parameter (436) that represents a power threshold, wherein the power threshold is used to discard a subset of the estimated plurality of symbol vectors.
  9. The receiving device (104) according to any of the claims 5 to 8, wherein at least one decoder of the plurality of decoders (412) is further configured to execute a de-mapping of each vector of the plurality of vectors associated with the first segregated symbol vector to obtain a plurality of part messages.
  10. The receiving device (104) according to claim 9, wherein the at least one decoder of the plurality of decoders (412) is further configured to concatenate the plurality of part messages to re-construct a message having a sequence of bits.
  11. A method (700) for a random-access communication, comprising: acquiring, by an encoder (208) of a transmitting device (102), an input message having a sequence of bits; forming, by the encoder (208) of the transmitting device (102), a plurality of blocks from the sequence of bits; and determining, by the encoder (208) of the transmitting device (102), a plurality of vectors for the plurality of blocks; constructing, by the transmitting device (102), a symbol vector based on the plurality of vectors, wherein the symbol vector is constructed by combining the plurality of vectors with each other through a Kronecker product, wherein the plurality of vectors correspond to a plurality of sub-constellations and the symbol vector corresponds to a constellation, and wherein the constellation is a cartesian product of the plurality of sub-constellations, and wherein a product of a vector size of each of the plurality of vectors is equal to a number of channel uses; and transmitting, by the transmitting device (102), the constructed symbol vector over a radio frequency, RF, signal to a receiving device (104), wherein the constructed symbol vector represents a symbol modulated in the radio frequency signal.
  12. A method (800) for a random-access communication, comprising: receiving, by a receiving device (104), a plurality of radio frequency signals concurrently from a plurality of transmitting devices (108); estimating, by the receiving device (104), a plurality of symbol vectors from the received plurality of radio frequency signals in digital domain, and segregate the plurality of symbol vectors, wherein a symbol vector is constructed by combining a plurality of vectors with each other through a Kronecker product, wherein the plurality of vectors corresponds to a plurality of sub-constellations and the symbol vector corresponds to a constellation, and wherein the constellation is a cartesian product of the plurality of sub-constellations, and wherein a product of a vector size of each of the plurality of vectors is equal to a number of channel uses; and decoding, by the receiving device (104), each segregated symbol vector of the estimated plurality of symbol vectors to obtain a plurality of decoded messages, wherein each decoded message has a sequence of bits that corresponds to data associated with a corresponding transmitting device of the plurality of transmitting devices (108).
  13. A computer program product comprising a non-transitory computer-readable storage medium having computer program code stored thereon, the computer program code being executable by the transmitting device of claim 1 to execute the steps of the method of claim 11.
  14. A computer program product comprising a non-transitory computer-readable storage medium having computer program code stored thereon, the computer program code being executable by the receiving device of claim 5 to execute the steps of claim 12.

Description

TECHNICAL FIELD The present invention relates generally to the field of wireless communication; and more specifically, to a transmitting device, a receiving device, and methods for random-access communication. BACKGROUND With the rapid increase in the number of communication devices in a network, concerns about communication reliability have become prominent. Traditionally, fixed access methods are used by conventional communication devices for communication of data in a network. In the fixed access methods, a given communication device is assigned either a fixed time slot or a fixed frequency to send data via a communication channel. The conventional fixed access methods are less efficient in terms of channel utilization because sometimes the given communication device may not have any data to transmit in the fixed time slot or in the fixed frequency. In certain scenarios, instead of the conventional fixed access methods, conventional random-access methods are used for a comparatively better utilization of the communication channel. In the random-access methods, a conventional communication device (e.g. a transmitter) is allowed to send data on the communication channel whenever it has some data to transmit. There is no need of a preassigned time slot or a fixed frequency for data transmission. The conventional random-access methods are typically classified into coherent and non-coherent methods. In coherent methods, the channel state is known to communication devices (i.e. both the transmitter and the receiver). In the conventional coherent methods, the transmitted data typically consists of two parts namely a pilot part and a data part. The pilot part is used at the conventional receiver for channel estimation and other operations related to processing of the data part, whereas the data part is used to carry information. In non-coherent methods, the channel state is supposed to be unknown to both the conventional transmitter and the conventional receiver. The traditional non-coherent methods use sparsity for extracting information from the transmitted data. Thus, the conventional random-access methods require additional parameters (e.g. the coherent methods require the pilot part and the non-coherent methods use sparsity in transmitted data), which increases the complexity at both the transmitter side and the receiver side. Moreover, the probability of decoding error is increased resulting in erroneous (or unreliable) recovery of data at the conventional receiver. Thus, there is a technical problem of inefficient waveform design and inadequate communication reliability in the conventional random-access methods. Therefore, in light of the foregoing discussion, there exists a need to overcome the aforementioned drawbacks associated with conventional communication devices and methods for random-access communication. JINSONG WU ET AL, "Three-Dimensional Combined Diversity Coding and Error Control Coding: Code Design and Diversity Analysis", ISCIT 2011, disclose and prove a full diversity construction with joint 3-D CDC and ECC, bit-interleaved coded complex diversity coding and symbol-interleaved coded complex diversity coding. WO 2018/231026 A1 discloses: A transmission apparatus: encodes information into a first bit sequence, using a polar code; outputs a second bit sequence by inputting the first bit sequence to an interleaver; modulates the second bit sequence into modulation symbols according to a modulation order; and transmits the modulation symbols. The interleaver: has an odd number of columns; and is configured to cyclically read and output, from column k, bits stored in row n of the interleaver, and cyclically read and output, from column k+a, bits stored in row n+1 of the interleaver, wherein a represents an integer which is not 0. NGO KHAC-HOANG ET AL, "A Multiple Access Scheme for Non-Coherent SIMO Communications", 2018 52ND ASILOMAR CONFERENCE ON SIGNALS, SYSTEMS, AND COMPUTERS, IEEE, (20181028), doi:10.1109/ACSSC.2018.8645403 introduce a multiple access scheme for non-coherent single-input multiple-output (SIMO) communications. They first define an individual codebook for each user as the image of a non-coherent single-user codebook of smaller dimension through a bijective mapping. They investigate the available options at the decoder, including linear equalization in the absence of reference symbols, and joint multi-user decoding. In particular, they propose greedy decoders that exploit the structure of the encoder mappings to separate the signals of different users, denoise, and decode each signal as in the single-user case. SUMMARY The present invention seeks to provide a transmitting device, a receiving device, and methods for random-access communication. The present invention seeks to provide a solution to the existing problem of inefficient waveform design and inadequate communication reliability in conventional random-access communication methods. An aim of the present invention is to