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:
Provided is a radio transmission device (100) which can flexibly cope with a request for assuring an error ratio feature during a high transmission rate, a request for increasing a cell coverage, or the like. The radio transmission device (100) includes a first subcarrier modulation unit (104) which forms a first subcarrier modulation signal obtained by converting a plurality of modulation signals into a frequency region; a second subcarrier modulation unit (105) which forms a second subcarrier modulation signal obtained by parallel conversion of a plurality of signals; an IFFT unit (111) which forms an OFDM signal by performing inverse Fourier transform on the first and the second subcarrier modulation signal; and a subcarrier mapping unit (110) which controls allocation of the first and the second subcarrier modulation signals.
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:
An encoding method and an encoder for creating a low-density parity check convolution code (LDDC-CC), sending a signal sequence after subjecting the code to an error-correction using the low-density parity check convolution code, and creating a low-density parity check code of a time-variant period (3g) by linear operations of first to 3g-th (letter g designates a positive integer) parity check polynomials and input data.
摘要:
Provided is a radio transmission device (100) which can flexibly cope with a request for assuring an error ratio feature during a high transmission rate, a request for increasing a cell coverage, or the like. The radio transmission device (100) includes a first subcarrier modulation unit (104) which forms a first subcarrier modulation signal obtained by converting a plurality of modulation signals into a frequency region; a second subcarrier modulation unit (105) which forms a second subcarrier modulation signal obtained by parallel conversion of a plurality of signals; an IFFT unit (111) which forms an OFDM signal by performing inverse Fourier transform on the first and the second subcarrier modulation signal; and a subcarrier mapping unit (110) which controls allocation of the first and the second subcarrier modulation signals.
摘要:
A base station device (10) communicates between a first terminal device and a second terminal device over the same channel by spatial multiplexing. The base station device (10) comprises an interference cancellation coefficient extractor (30) that extracts an interference cancellation coefficient from a signal received from the first terminal device to cancel interference on a propagation channel with the first terminal device in advance, and transmits a pilot signal that contains information related to the interference cancellation coefficient to the second terminal device. In addition, the base station device (10) also comprises an interference canceller (16) that uses the interference cancellation coefficient to cancel an interference component from transmission data to be transmitted over the same channel, and transmits the transmission data from which the interference component has been canceled by the interference canceller (16) to the first terminal device and the second terminal device over the same channel. A wireless communication system is provided which, in a multi-user MIMO, suppresses superimposed interference components resulting from channel fluctuations and channel estimation errors when interference cancellation is performed in advance in a base station unit on a modulated signal to be transmitted.
摘要:
A base station device (10) communicates between a first terminal device and a second terminal device over the same channel by spatial multiplexing. The base station device (10) comprises an interference cancellation coefficient extractor (30) that extracts an interference cancellation coefficient from a signal received from the first terminal device to cancel interference on a propagation channel with the first terminal device in advance, and transmits a pilot signal that contains information related to the interference cancellation coefficient to the second terminal device. In addition, the base station device (10) also comprises an interference canceller (16) that uses the interference cancellation coefficient to cancel an interference component from transmission data to be transmitted over the same channel, and transmits the transmission data from which the interference component has been canceled by the interference canceller (16) to the first terminal device and the second terminal device over the same channel. A wireless communication system is provided which, in a multi-user MIMO, suppresses superimposed interference components resulting from channel fluctuations and channel estimation errors when interference cancellation is performed in advance in a base station unit on a modulated signal to be transmitted.
摘要:
A multicarrier transmitter and a multicarrier receiver improve the reception characteristic of hierarchical modulation multiplex communication. A base station transmits a multicarrier superposition signal of a modulated signal addressed to a far user (a far-user addressed signal) and a modulated signal addressed to a near user (a near-user addressed signal) and modulated with a modulation multivalued number different from that of the far-user addressed signal. The base station separates the far-user addressed signal into frequency range signals, serial/parallel-transforms the near-user addressed signal to generate N1 parallel signals, and combines the generated N1 frequency components and the N1 parallel signals. Since the far-user receiver changes the near-user addressed signal into white noise by inverse discrete Fourier transform, the far-user receiver can demodulate the far-user addressed signal with high accuracy. The near-user receiver can acquire the signal addressed thereto with high accuracy by subtracting the far-user addressed signal from the received signal.
摘要:
A multicarrier transmitter and a multicarrier receiver both enabling improvement of the reception characteristic of hierarchical modulation multiplex communication. A base station (100) transmits a multicarrier signal which is a superposition of a modulated signal addressed to a far user and a modulated signal addressed to a near user and modulated with a modulation multivalued number different from that of the modulated signal addressed to the far user. The base station (100) comprises a DFT section (120), an S/P section (125), and a combining section (145). The DFT section (120) separates the modulated signal addressed to the far user into signals in frequency ranges for each symbol. The S/P section (125) serial/parallel-transforms the modulated signal addressed to the near user to generate N1 parallel signals. The combining section (145) combines the N1 frequency components generated by the DFT section (120) and the N1 parallel signals. Since the far user receiver can change the modulated signal addressed to the near user into white noise by IDFT, the far user receiver can demodulate the modulated signal addressed to the far user with high accuracy. The near user receiver can acquire the signal addressed thereto with high accuracy by subtracting the modulated signal addressed to the far user, which is an interference signal, from the received signal.