1247 results about "Coded modulation" patented technology

A pipelined digital data receiver for a cable TV headend which is capable of receiving DOCSIS 1.0 or 1.1 or advanced PHY TDMA or SCDMA bursts having programmable symbol rates and programmable modulation types as well as a host of other burst parameters such at Trellis code modulation on or off, scrambling on or off, various values for Reed-Solomon T number and codeword length. The receiver has an RF section to filter and digitize incoming RF signals. It also has an input section to detect impulse noise and do match filtering and despread SCDMA bursts. A timing recovery section recovers the symbol clock and detects the start of bursts and collisions. A rotational amplifier and equalizer calculate and track gain, phase and frequency offsets and correct symbols and calculates equalization coefficients. A decoder section decodes TCM and non TCM bursts, and a Reed-Solomon decoder section reconstructs RS codewords and uses them to error correct the payload data.

A system for compensating for in-phase and quadrature (I/Q) imbalances for multiple antenna systems (MAS) with multi-user (MU) transmissions (defined with the acronym MU-MAS), such as distributed-input distributed-output (DIDO) communication systems, comprising multicarrier modulation, such as orthogonal frequency division multiplexing (OFDM). For example, one embodiment of the system comprises one or more coding modulation units to encode and modulate information bits for each of a plurality of wireless client devices to produce encoded and modulated information bits; one or more mapping units to map the encoded and modulated information bits to complex symbols; and a MU-MAS or DIDO IQ-aware precoding unit to exploit channel state information obtained through feedback from the wireless client devices to compute MU-MAS or DIDO IQ-aware precoding weights, the MU-MAS or DIDO IQ-aware preceding unit precoding the complex symbols obtained from the mapping units using the weights to pre-cancel interference due to I/Q gain and phase imbalances and/or inter-user interference.

A multi-level cell (MLC) memory device may include: a MLC memory cell; an outer encoder that encodes data using a first encoding scheme to generate an outer encoded bit stream; and a TCM modulator that applies a program pulse to the MLC memory cell to write the data in the MLC memory cell. The program pulse may be generated by TCM modulating the outer encoded bit stream. A method of storing data in a MLC memory device, reading data from the MLC memory device, or storing data in and reading data from the MLC memory device may include: encoding data using a first encoding scheme to generate an outer encoded bit stream; and applying a program pulse to a MLC memory cell of the MLC memory device to write the data in the MLC memory cell. The program pulse may be generated by TCM modulating the outer encoded bit stream.

A method of resetting a trellis-coded modulation (TCM) encoder to a known state, the TCM encoder including a reset input that resets the TCM encoder to the known state when held at a reset level for a plurality of symbol clock cycles, the method including identifying an event to occur in the future that requires the TCM encoder to be reset to the known state; and holding the reset input of the TCM encoder at the reset level beginning the plurality of clock symbol cycles before a time the event will occur so that the TCM encoder will be reset to the known state immediately before the event occurs.

A method of building systematically a multi-dimensional (n, D, L) circular trellis coded modulation (CTCM) encoder with properties of optimal energy efficiency, strong tail biting and maximum minimum distance (d_min) of trellis paths is disclosed. In addition, a communication system for use in a power limited channel application is disclosed comprising a circular trellis coded modulation (CTCM) encoder with permuted state structure for encoding based on a circular trellis path associated with a sequence of digital information bits and a set of simplexes identified for the path from a multi-dimensional signal constellation; a transmitter coupled to said CTCM encoder for transmitting said sequence of channel symbols over said channel; a receiver for receiving a transmission from said transmitter including said sequence of channel symbols and any noise induced therein; and a CTCM decoder coupled to said receiver for decoding the received transmission without knowledge of the starting state of the circular trellis path of the CTCM encoder to recover the sequence of information bits. Apparatus and methods of encoding and decoding are also disclosed utilizing a combination of circular trellis-coded modulation with permuted state structure and simplex signal constellation techniques for use in the digital communication system.

A system and a method for medium wide band communications using impulse radio techniques. The method of transmitting medium wide band signals includes the steps of producing a sinusoidal signal and a train of preferably Gaussian shaped pulses. The method also includes the steps of multiplying the sinusoidal signal by the train of pulses to produce a train of sinusoidal bursts, and transmitting the train of sinusoidal bursts. The center frequency of the transmitted signal consisting of the train of sinusoidal bursts can be controlled by selecting an appropriate frequency of the sinusoidal signal. The bandwidth of the transmitted signal can be controlled by selecting an appropriate width of the pulses in the train of pulses. Information and/or coding modulation can be accomplished by adjusting the time position and/or phase of the sinusoidal bursts.

The invention provides an upstream multiple access method combined with orthogonal multiple access and nonorthogonal multiple access, comprising the steps as follows: a base station performing orthogonal partition to a band width resource of a multiple access channel according to channel state information and business requirement of K users in the coverage range thereof to obtain L orthogonal sub-channels of the multiple access channel; performing nonorthogonal partition to each orthogonal sub-channel to obtain one or a plurality of sub-layer channels, the base station determining a transmission mode of each user according to channel state information, business requirement, bandwidth and power resource partitioning condition of the multiple access channel of K users in the coverage range thereof and respectively and correspondingly transmitting to each user; performing coded modulation to information bits of the transmission mode by each user to obtain a transmitting signal with the information bits, and outputting to the multiple access channel. The upstream multiple access method combined with orthogonal multiple access and nonorthogonal multiple access of the invention reduces distance of multi-user united reachable rate upper bound and theoretical cycle, and reduces receiving delay and improves error spread to reduce realizing complexity.

The present invention provides a design framework that is used to develop new types of constrained turbo block convolutional (CTBC) codes that have higher performance than was previously attainable. The design framework is applied to design both random and deterministic constrained interleavers. Vectorizable deterministic constrained interleavers are developed and used to design parallel architectures for real time SISO decoding of CTBC codes. A new signal mapping technique called constrained interleaved coded modulation (CICM) is also developed. CICM is then used to develop rate matching, spatial modulation, and MIMO modulation subsystems to be used with CTBC codes and other types of codes. By way of example, embodiments are primarily provided for improved 5G LTE and optical transport network (OTN) communication systems. Detailed descriptions of embodiments are also provided that combine aspects of MIMO and spatial modulation systems to improve bandwidth efficiency. Such embodiments are applicable to multi-antenna and single antenna MIMO systems as well as multichannel systems, OFDM systems, and TDM systems.

IPHD (Iterative Parallel Hybrid Decoding) of various MLC (Multi-Level Code) signals. Various embodiments are provided by which IPHD may be performed on MLC LDPC (Multi-Level Code Low Density Parity Check) coded modulation signals mapped using a plurality of mappings. This IPHD may also be performed on MLC LDPC coded modulation signals mapped using only a singe mapping as well. In addition, various embodiments are provided by which IPHD may be performed on ML TC (Multi-Level Turbo Code) signals. These principles of IPHD, shown with respect to various embodiments IPHD of MLC LDPC coded modulation signals as well as the IPHD of ML TC signals, may be extended to performing IPHD of other signal types as well. Generally speaking, based on the degree of the MLC signal, a corresponding number of parallel paths operate in cooperation to decode the various levels of the MLC signal.

The invention discloses a method for sending uplink control information on a physical uplink shared channel, including: determining the following parameters: the maximum number of REs A available for the initial PUSCH, the number of bits of service information before coding B, the code rate offset, and the current The number of carriers D used for PUSCH transmission in the subframe, the maximum number of REs occupied by the modulation symbols encoded by the CQI/PMI information E; determine the target length of ACK/NACK information or the target length of /RI information according to the determined parameters, and /or the target length of the CQI/PMI information; encode and modulate the uplink control information according to the determined target length of the ACK/NACK information or the target length of the RI information and/or the target length of the CQI/PMI information, and together with the service information Multiplexed to PUSCH to send. The invention also discloses a device for sending uplink control information on the physical uplink shared channel. The invention maintains the compatibility with the LTE version 8 protocol, and the technical solution is relatively simple to implement.

The invention provides a block-encoded modulation scheme using multi-level partitioning techniques. This scheme is made transparent to phase ambiguities of ±pi/2 and of pi, by means of differential encoding and appropriate mapping, it is applicable to 16-QAM modulation, and it has theoretical encoding gain that is optimal for the rate of the code. The decoder associated with this scheme uses the Wagner algorithm which is much less complicated to implement than the Viterbi algorithm or than the Reed-Solomon algorithm.

Systems and methods for transmitting data, including encoding one or more streams of input data using one or more adaptive Low Density Parity Check (LDPC) encoders, wherein the encoders generate one or more signal constellations; modulate one or more signals using hybrid multidimensional coded modulation; apply orthogonal prolate spheroidal wave functions as electrical basis functions; generate one or more spectral band group signals by selecting and combining two or more spectral band groups with center frequencies that are orthogonal to each other; and spectral-mode-multiplex and transmit the one or more adaptive LDPC-coded data streams including the one or more spectral band group signals combined into corresponding spatial modes over a transmission medium.

The invention relates to a high precision speed and distance measuring laser radar system and a speed and distance measuring method. The basic principle of the invention is as follows: linear chirp modulation and pseudo-random code modulation of lasers are performed; most lasers after modulation are taken as outgoing lasers and transmitted by a telescope; a small part of the lasers is taken as local oscillator beams and used for coherent detection; laser echo signals are divided into two parts; distance information is obtained after related operation of one part of the laser echo signals and original pseudo-random codes; the frequency difference of the local oscillator beams and echo signal beams is obtained after coherent detection of the other part of the laser echo signals and the local oscillator beams and pulse compression, and simultaneously comprises the distance information and Doppler shift; the Doppler shift is obtained through mathematical manipulation, thereby speed information is obtained. The high precision speed and distance measuring laser radar system and a speed and distance measuring method of the invention is characterized in that the speed information and the distance information of a target can be obtained with high precision.

A signal diversity method of an OFDM system comprises the following steps: carrying out data decoding, modulation and rotation-modulation by a transmitting end, and storing the symbols of the processed data blocks; subjecting the symbols of the data blocks of a plurality of users in a memory to grouping and time-frequency interleaving, OFDM time-frequency resource allocation and Q-path interleaving according to the set number of the users, respectively subjecting the symbols of each data block to IFFT operation and CP addition after zero padding according to the OFDM modulation length, then transmitting the data; and subjecting the symbols of the data blocks to de-CP and FFT operations after a receiving end receives the data, carrying out phase compensation and zero removal, and sequentially subjecting the symbols of the obtained data blocks to Q-path de-interleaving, rotation demodulation, time-frequency de-interleaving and coding to obtain the desired data information. By adopting OFDM technique and rotation modulation technique and by selecting an optimal rotation angle, the method can acquire signal diversity gain and maximal performance improvement, thereby improving the system performance.

A transmitting apparatus, a receiving apparatus and methods of controlling these apparatuses are provided. The transmitting apparatus includes: an input processor configured to process a plurality of input streams to generate a plurality of base band frames; a bit interleaved and coded modulation (BICM) processor configured to perform forward error correction (FEC) coding, constellation mapping, and interleaving on the plurality of baseband frames; a symbol generator configured to add signaling data to the plurality of baseband frames output from the BICM processor to generate an orthogonal frequency division multiplexing (OFDM) symbol; and a transmitter configured to select at least one of a plurality of pilot patterns based on a fast Fourier transform (FFT) size and a guard interval fraction, insert a pilot in the OFDM symbol according to the selected pilot pattern, and transmit a stream including the pilot-inserted OFDM symbol. Thus, a data transmission rate is increased and accurate channel estimation is performed, through inserting different pilots according to different FFT sizes and guard interval fractions.

Embodiments of the invention provide a method and device for determining channel reliability in polarization coding modulation. The method comprises: dividing a channel into m binary input channels, carrying out channel polarization transformation, and using a Gaussian approximation algorithm to calculate a log likelihood ratio Gaussian distribution mean corresponding to the polarization sub-channels according to the equivalent noise variance of the binary input channels obtained by splitting, so as to determine the reliability of the polarization sub-channels. Since the method provided by the invention adopts the Gaussian approximation algorithm, the problem of calculation complexity caused by calculating the channel reliability by using a density evolution tool is avoided. Compared with the scheme of calculating the channel reliability by using the density evolution tool, the calculation complexity of the method provided by the invention is obviously reduced.

The invention discloses a polar code encoding modulation method applicable to any high-order modulation. The method comprises the concrete steps of (1), calculating the code length of a polar code; (2), generating an encoding matrix of the polar code; (3), generating the encoding matrix after puncturing; (4), generating code words of the polar code; (6) interleaving the code words; and (7), carrying out high-order modulation. According to the method, the code words are interleaved by employing a grouping interleaving technology, the polar effect of a channel is intensified with the combination of the polar characteristic of the polar code itself and the capacity differences of high-order modulation sub-channels, and the performance of the polar code is improved. According to the method, the encoding matrix is punctured according to a column weight, the decoding delay is reduced, and the programming realization complexity of a decoding algorithm in a programmable device is reduced. The flexibility of the polar code in the high-order modulation is improved, and the polar code has good performance.

Embodiments of the present invention provide multi-level signal memory with LDPC and interleaving. Thus, various embodiments of the present invention provide a memory apparatus that includes a memory block comprising a plurality of memory cells, each memory cell adapted to operate with multi-level signals. Such a memory apparatus also includes a low density parity check (LDPC) coder to LDPC code data values to be written into the memory cells and an interleaver adapted to apply bit interleaved code modulation (BICM) to the LDPC coded data values to generate BICM coded data values. Other embodiments may be described and claimed.

The present invention discloses a self-adapting cooperative retransmission method based on the self-adapting coding modulation. The method selects an appropriate coding modulation plan grade and a largest retransmission number for transmitting the data package according to the channel state information of the direct transmission link from a source end to a target end and the service quality request of different services. Because of the broadcast characteristic of the radio channel, the target end and a relay node can receive the data simultaneously. If the target end does not decode correctly, the retransmission is actuated. The retransmission by the source end or the relay node is determined by the selected coding modulation plan and whether the relay node correctly receives the data package. The invention combines the self-adapting coding modulation technique, a hybrid automatic retransmission technique and cooperative diversity for consideration. The cooperation is selected to execute at the time when the cooperative gain is evident. The incorrect or no-gain cooperation is avoided thereby improving the transmission quality and effectively optimizing the whole capability of the system at the state that the spending of the cooperation signaling is reduced as possible.

The invention relates to a code modulation method, demodulation and decoding method and system which are used for digital communication systems. The code modulation method comprises the following steps of: carrying out channel coding and bit interleaving on an input information bit to obtain a code bit; and carrying out M-point K-dimensional Gaussian constellation mapping on the code bit to obtain a constellation mapping symbol, i.e. a K-dimensional real number vector, wherein M and K are both integers more than 1. The method and the system can ensure that the performances of a code modulation system and a corresponding demodulation and decoding system approach channel capacity in high and low frequency spectrums under the condition of a plurality of channels, such as AWGN (Additive WhiteGaussian Noise), attenuation and the like, and consider the throughput capacity of the system at the same time.