Methods and apparatus for decoding received uplink transmissions using log-likelihood ratio optimization. In an embodiment, a method includes soft-demapping resource elements based on soft-demapping parameters as part of a process to generate log-likelihood ratios (LLR) values, decoding the LLRs to generate decoded data, and identifying a target performance value. The method also includes determining a performance metric from the decoded data, and performing a machine learning algorithm that dynamically adjusts the soft-demapping parameters to move the performance metric toward the target performance value.

Probabilistic constellation shaping (PCS) is applied to a desired probability distribution over the 2-D constellation points. Constellation points are partitioned into multiple disjoint sets in which all the constellation points within a subset have the same energy level (i.e., amplitude) or distance from the origin on the complex plane. Each of the sets may be further subdivided into smaller disjoint sets of constellation points to facilitate labeling of the constellation points. The sets may be indexed from 0 to the total number of disjoint sets to form an index set. The desired distribution may then be applied over the index set either using a distribution matcher (DM) or using a lookup table. The desired distribution may be generated before forward error correction (FEC) encoding that preserves the generated amplitude distribution through FEC encoding of data bits. The scheme may map the FEC encoded data bits to the constellation points, such that the probability of occurrence of each signal set (with a specific energy level) follows the desired probability distribution within a fixed codeword length. In addition, PCS can be applied to both square and non-square constellations, which may or may not be arranged on a Cartesian grid.

Described herein is the generation of a signal for an analysis of a communication network based on a first version of a radio signal transmitted from a first node of the radio communication system to a second node of the radio communication system received at a passive node by detecting deviations of the first version of the transmitted radio signal from a second version of the radio signal received at the second node, and generating the signal based on the deviations.

Transmission quality is improved in an environment in which direct waves dominate in a transmission method for transmitting a plurality of modulated signals from a plurality of antennas at the same time. All data symbols used in data transmission of a modulated signal are precoded by hopping between precoding matrices so that the precoding matrix used to precode each data symbol and the precoding matrices used to precode data symbols that are adjacent to the data symbol in the frequency domain and the time domain all differ. A modulated signal with such data symbols arranged therein is transmitted.

A first communication device and a second communication device for an iterative code design are provided. The first communication device generates and transmits sets of parity symbols and receives the transmitted sets of parity symbols from a second communication device. The sets of parity symbols are generated based on using a first generator device and based previously transmitted systematic symbols and computed noise values. The second communication device buffers received systematic symbols and sets of parity symbols and jointly decodes them. Thereby, an iterative code design is provided with improved performance. Furthermore, the disclosure also relates to corresponding methods and a computer program.

A receiver may include a first filter configured to generate a first estimation of a symbol of a received signal and a second filter configured to generate a second estimation of the symbol of the received signal. The receiver may also include a decoder configured to decode the symbol using one of the first estimation and the second estimation and a decision circuit configured to select one of the first estimation and the second estimation to provide to the decoder for decoding of the symbol based on a comparison of the first estimation to an estimation threshold.

Disclosed is a precoding method comprising the steps of: generating a first coded block and a second coded block with use of a predetermined error correction block coding scheme; generating a first precoded signal z1 and a second precoded signal z2 by performing a precoding process, which corresponds to a matrix selected from among the N matrices F[i], on a first baseband signal s1 generated from the first coded block and a second baseband signal s2 generated from the second coded block, respectively; the first precoded signal z1 and the second precoded signal z2 satisfying (z1, z2).sup.T=F[i] (s1, s2).sup.T; and changing both of or one of a power of the first precoded signal z1 and a power of the second precoded signal z2, such that an average power of the first precoded signal z1 is less than an average power of the second precoded signal z2.

The present disclosure provides techniques for bandwidth constrained communication systems with frequency domain information processing. A bandwidth constrained equalized transport (BCET) communication system can include a transmitter, a communication channel, and a receiver. The transmitter can include a pulse-shaping filter that intentionally introduces memory into a signal in the form of inter-symbol interference, an error control code (ECC) encoder, a multidimensional fast Fourier transform (FFT) processing block that processes the signal in the frequency domain, and a first interleaver. The receiver can include an information-retrieving equalizer, a deinterleaver with an ECC decoder, and a second interleaver joined in an iterative ECC decoding loop. The communication system can be bandwidth constrained, and the signal can comprise an information rate that is higher than that of a communication system without intentional introduction of the memory at the transmitter.

A first wireless device may receive, from a second wireless device, a transmission associated with an MLC scheme. The MLC scheme may include a plurality of bits with at least one first bit corresponding to a first level of the plurality of bits and at least one second bit corresponding to a second level of the plurality of bits. The at least one first bit may be coded with a first level of complexity, but the at least one second bit may be coded with either the first level of complexity or a second level of complexity, where the first level of complexity may be a higher level of complexity than the second level of complexity. The first wireless device may decode the at least one first bit and the at least one second bit using a decoder having a corresponding level of complexity.

The invention relates to an interconnection network for forward error correction encoders and decoders, including N input terminals, N output terminals, and M stages. Each stage includes switching elements having input pins and output pins. The input pins of the switching elements of the first stage are connected to the input terminals, and the output pins of the switching elements of the last stage are connected to the output terminals. The input and output pins of the switching elements of immediately successive stages are connected in a hardwired fashion so as to form a plurality of interconnection sub-networks for routing respective input values from respective output pins of the switching elements of the first stage to respective input pins of the switching elements of the last stage.