Abstract: A wireless communication terminal includes a base station communication part which communicates with a base station; an interterminal communication part which communicates with another wireless communication part; a communication failure detector which detects a communication failure with a first connected base station serving as a base station connected thereto; and a communication resume processor which carries out an interterminal communication with another wireless communication terminal so as to communicate with a second connected base station, connected to another wireless communication terminal, via another wireless communication terminal when a communication failure is detected with the first connected base station, thus carrying out a process of resuming a communication upon detecting the communication failure.

Abstract: A channel information compressing apparatus of the present invention includes a DCT part that performs discrete cosine transform on channel information (CSI) representing the state of a communication channel, and an information compressor that compresses high frequency components of information included in discrete cosine transform data which is produced by way of discrete cosine transform, thus compressing information while maintaining a good accuracy of channel information.

Abstract: A wireless communication terminal includes a base station communication part which communicates with a base station; an interterminal communication part which communicates with another wireless communication part; a communication failure detector which detects a communication failure with a first connected base station serving as a base station connected thereto; and a communication resume processor which carries out an interterminal communication with another wireless communication terminal so as to communicate with a second connected base station, connected to another wireless communication terminal, via another wireless communication terminal when a communication failure is detected with the first connected base station, thus carrying out a process of resuming a communication upon detecting the communication failure.

Abstract: A radio terminal includes: a base station connection communication portion that performs base station connection communication with a base station; a communication quality determination portion that determines a communication quality of the base station connection communication to acquire a determination result of the communication quality; an inter-terminal communication control portion that decides a radio resource to be used for inter-terminal communication from radio resources that the base station uses, based on the determination result of the communication quality; and an inter-terminal communication portion that performs inter-terminal communication with another radio terminal, using the radio resource decided by the inter-terminal communication control portion.

Abstract: An interleaving apparatus includes an interleaver for concurrently sorting bits of input data according to the predetermined interleave pattern; a switch including an input terminal supplied with an input signal subject to an interleave process, an input terminal supplied with a signal output from the interleaver, an output terminal for outputting an output signal, representing the result of interleaving completed on the input signal, and an output terminal for outputting a signal input to the interleaver, thus switching connection between the input terminals and the output terminals; and a controller for controlling the switch to use the interleaver once or repeatedly use it multiple times in response to each of interleave patterns.

Abstract: A channel state information compressing apparatus includes a time-to-frequency region converter that converts a region for channel state information which indicates a state of each communication channel from a time region to a frequency region; and an adaptive selector that selects each frequency component to be included in compressed data based on electric power of the frequency component from among frequency region data obtained by the time-to-frequency region converter. The channel state information compressing apparatus outputs the compressed data consisting of each selected frequency component, and information for identifying each frequency component which forms the compressed data.

Abstract: A receiver receives a signal from a transmitter via communication channels, informs the transmitter of channel state information, and includes a channel correlation value computation unit that computes a correlation value assigned to each channel state information combination; a conversion input data generation unit that determines a channel state information combination having a relatively large correlation based on the correlation value, to be conversion input data; a time-to-frequency region conversion unit that converts the region of the conversion input data from a time region to a frequency region; an information compressing unit that compresses information of a frequency component included in the conversion input data obtained by the time-to-frequency region conversion unit; and a transmitting unit that sends the transmitter, information-compressed data obtained by the information compressing unit and information used for isolating the channel state information items included in the conversion input da

Abstract: In a digital signal transmission method according to the present invention, when N1 is the number of code multiplexes of a first transmit block including an information bit and part of a parity bit, and N2 is the number of code multiplexes of a subsequent transmit block including the remaining parity bit, a spread multiplexer 104 performs spread multiplexing of each block in a relationship of N1>N2.

Abstract: A channel information compressing apparatus of the present invention includes a DCT part that performs discrete cosine transform on channel information (CSI) representing the state of a communication channel, and an information compressor that compresses high frequency components of information included in discrete cosine transform data which is produced by way of discrete cosine transform, thus compressing information while maintaining a good accuracy of channel information.

Abstract: A receiver receives a signal from a transmitter via communication channels, informs the transmitter of channel state information, and includes a channel correlation value computation unit that computes a correlation value assigned to each channel state information combination; a conversion input data generation unit that determines a channel state information combination having a relatively large correlation based on the correlation value, to be conversion input data; a time-to-frequency region conversion unit that converts the region of the conversion input data from a time region to a frequency region; an information compressing unit that compresses information of a frequency component included in the conversion input data obtained by the time-to-frequency region conversion unit; and a transmitting unit that sends the transmitter, information-compressed data obtained by the information compressing unit and information used for isolating the channel state information items included in the conversion input da

Abstract: A channel state information compressing apparatus includes a time-to-frequency region converter that converts a region for channel state information which indicates a state of each communication channel from a time region to a frequency region; and an adaptive selector that selects each frequency component to be included in compressed data based on electric power of the frequency component from among frequency region data obtained by the time-to-frequency region converter. The channel state information compressing apparatus outputs the compressed data consisting of each selected frequency component, and information for identifying each frequency component which forms the compressed data.

Abstract: In a digital signal transmission method according to the present invention, when N1 is the number of code multiplexes of a first transmit block including an information bit and part of a parity bit, and N2 is the number of code multiplexes of a subsequent transmit block including the remaining parity bit, a spread multiplexer 104 performs spread multiplexing of each block in a relationship of N1>N2.