摘要:
The invention is embodied for solving a problem of occurrence of degradation of the reception characteristic caused by the interference signal component if a symbol making a determination error is contained or if an error factor caused by a propagation channel estimation error or a hardware error (carrier frequency error, sampling frequency error) is contained at the interference canceling time in a wireless communication apparatus for iteratively decoding and receiving a spatial multiplex signal. A wireless communication apparatus 100 according to the invention has an error estimator 13 for estimating an error of a replica signal at the interference canceling time and a weighter 14 for weighting likelihood information for a spatial multiplex signal separated and combined after interference is canceled based on output of the error estimator 13, whereby if an error of the replica signal at the interference canceling time is contained, a good reception characteristic can be provided.
摘要:
The invention is embodied for solving a problem of occurrence of degradation of the reception characteristic caused by the interference signal component if a symbol making a determination error is contained or if an error factor caused by a propagation channel estimation error or a hardware error (carrier frequency error, sampling frequency error) is contained at the interference canceling time in a wireless communication apparatus for iteratively decoding and receiving a spatial multiplex signal. A wireless communication apparatus 100 according to the invention has an error estimator 13 for estimating an error of a replica signal at the interference canceling time and a weighter 14 for weighting likelihood information for a spatial multiplex signal separated and combined after interference is canceled based on output of the error estimator 13, whereby if an error of the replica signal at the interference canceling time is contained, a good reception characteristic can be provided.
摘要:
An MIMO receiver and MIMO communication system which can have a small hardware scale even if the number of antennas used for MIMO communication. In a radio communication device (200), a receiving section (220) receives a spatially multiplexed signal generated by mutually-different and spatially multiplexing transmission signals, a first signal demultiplexing section (230) subjects a linear operation to the received spatial multiplexed signal to demultiplex the spatial multiplexed signal, and a second signal demultiplexing section (240) demultiplexer the demultiplexed spatially multiplexed signal into the transmission signals. When the received signal is demultiplexed by a single demultiplexing, as the number of multiplexed spatial multiplexed signal increases, the demultiplexer becomes complicated, and the hardware scale increases. When the received signal is demultiplexed by a plurality of demultiplexings, the hardware scale is relatively small.
摘要:
It is an object to provide a wireless base station and a terminal equipment capable of shortening the processing time by not requiring the detection of the spatial correlation coefficient, which is required in general technology, and simplifying the selection process for terminal equipments to be connected to each other in a wireless base station that performs spatial multiplexing transmission to a plurality of terminal equipments and a terminal equipment responding for spatial multiplexing transmission.A terminal equipment 12 includes an interference cancellation capability information data maintaining section 20 that maintains interference cancellation capability information data indicating the interference cancellation capability of the terminal equipment 12 and signals the interference cancellation capability information data to a wireless base station 1. The wireless base station 1 includes a control signal extracting unit 3 and a spatial multiplexing controller 4, and the spatial multiplexing controller 4 selects one or more terminal equipments 12 for spatial multiplexing connection on the basis of the interference cancellation capability information data extracted from a reception signal from the terminal equipment 12.
摘要:
A wireless network system including a first terminal for sending a request-to-send signal including information on a medium use period to a second terminal before sending data, receiving a clear-to-send signal from the second terminal, and sending data to the second terminal during the medium use period; the second terminal for receiving the request-to-send signal and sending the clear-to-send signal; a third terminal for receiving the request-to-send signal and transmitting data to a fourth terminal during the medium use period; and the fourth terminal. Thus, it is possible to prevent occurrence of a problem that when it is judged that the wireless channel is being used, transmission of the station is suppressed.
摘要:
A multiantenna receiving device is provided to make it possible to cope with both improvement in error rate characteristic and simplification in structure. The multiantenna receiving device is comprised of soft judgement output units for carrying out a soft judgement of a modulation signal in accordance with signal point distances between a plurality of candidate signal points with respect to a plurality of multiplexed modulation signals and a receiving signal, decoding units for obtaining digital data of the modulation signals by using the judged results obtained by the soft judgement output units, and signal point decreasing units for decreasing the number of the candidate signal points used in the soft judgement output units by recursively using a part of the digital data except self-modulation signals obtained by the decoding units.
摘要:
A multiantenna receiving device is provided to make it possible to cope with both improvement in error rate characteristic and simplification in structure. The multiantenna receiving device is comprised of soft judgement output units for carrying out a soft judgement of a modulation signal in accordance with signal point distances between a plurality of candidate signal points with respect to a plurality of multiplexed modulation signals and a receiving signal, decoding units for obtaining digital data of the modulation signals by using the judged results obtained by the soft judgement output units, and signal point decreasing units for decreasing the number of the candidate signal points used in the soft judgement output units by recursively using a part of the digital data except self-modulation signals obtained by the decoding units.
摘要:
An encoder and decoder using LDPC-CC (Low Density Parity Check-Convolutional Codes) is disclosed. The encoder exhibits encoding rates realized with a small circuit-scale and a high data reception quality. In the encoder (200), an encoding rate setting unit (250) sets an encoding rate (s−1)/s (s=z), and an information creating unit (210) sets information including from information Xs,i to information Xz−1,i to zero. A first information computing unit (220-1) receives information X1,i at time point i to compute the X1(D) term of formula (1). A second information computing unit (220-2) receives information X2,i at time point i to compute the X2(D) term of formula (1). A third information computing unit (220-3) receives information X3,i at time point i to compute the X3(D) term of formula (1). A parity computing unit (230) receives parity Pi−1 at time point i−1 to compute the P(D) of formula (1). The exclusive OR of the results of the computation is obtained as parity Pi at time i. Ax.
摘要:
A low-density parity check convolution code (LDPC-CC) is made, and a signal sequence is sent after subjected to an error-correcting encodement using the low-density parity check convolution code. In this case, a low-density parity check code of a time-variant period (3g) is created by linear operations of first to 3g-th (letter g designates a positive integer) parity check polynomials and input data.
摘要:
A spatial filtering adaptable for an interference wave that appears unsteadily can be implemented and also an interference canceling ability can be increased even in a condition that the interference wave does not steadily exist. At a time of non-active communication, the signals from a plurality of interference source radio communication devices 2 are received in advance by an interference signal receiving section 6 as the pre-process mode, then a resultant interference correlation matrix RI is stored in a storing section 7, and then an interference wave receiving antenna weight WI used to receive selectively the transmission signals from the interference source radio communication devices 2 is prepared based on the resultant interference correlation matrix RI. At a time of communication, the operation goes to the receiving process mode to normally receive the signal by a signal separating section 9, and a variation of the interference wave component is detected by an interference wave level detecting section 8 based on a signal power received using the interference wave receiving antenna weight WI. When the interference wave appears or changes, a desired wave separating/receiving antenna weight used to reduce the interference by using a new interference correlation matrix is changed adaptively.