Abstract: In a wireless communication system, a terminal device and a base station device communicate using frequency bands selected from among a plurality of frequency bands. The base station device selects a frequency band used for a downlink and a frequency band used for an uplink as frequency bands used for communication with the terminal device from among the plurality of frequency bands, selects an association between the frequency band used for the downlink and the frequency band used for the uplink among the selected frequency bands, and transmits information indicating the selected frequency bands and information indicating the association containing identification information of the association using a signal specific to the terminal device.

Abstract: A radio communication system includes transmission/reception devices which perform communication by dynamically switching a first transmission mode and a second transmission mode having a lower quality than the first transmission mode, wherein the transmission/reception devices have a transmission mode decision means which fixes a transmission mode upon communication to the first transmission mode for a given period of time.

Abstract: A radio communication system includes transmission/reception devices which perform communication by dynamically switching a first transmission mode and a second transmission mode having a lower quality than the first transmission mode, wherein the transmission/reception devices have a transmission mode decision means which fixes a transmission mode upon communication to the first transmission mode for a given period of time.

Abstract: A mobile station device, which communicates with a base station device, includes a control signal generator that initiates or terminates a cell search based on a reception quality value of a radio wave transmitted from the base station device, and a moving speed of the mobile station device.

Abstract: In a wireless communication system, a terminal device and a base station device communicate using frequency bands selected from among a plurality of frequency bands. The base station device selects a frequency band used for a downlink and a frequency band used for an uplink as frequency bands used for communication with the terminal device from among the plurality of frequency bands, selects an association between the frequency band used for the downlink and the frequency band used for the uplink among the selected frequency bands, and transmits information indicating the selected frequency bands and information indicating the association containing identification information of the association using a signal specific to the terminal device.

Abstract: A synchronization device including a plurality of counter sections each outputting a numerical signal indicating a counted number by detecting a clock, the synchronization device includes: a first counter section which outputs the numerical signal; a counter synchronization signal output section which outputs a counter synchronization signal indicating the same number as the number indicated by the numerical signal output by the first counter section; and a second counter section which outputs a numerical signal indicating the same number at the same timing as that of the first counter section based on the number indicated by the counter synchronization signal output by the counter synchronization signal output section.

Abstract: A mobile communication device includes a plurality of antennas which transmits and receives a radio signal, and a baseband processor which selects a transmission antenna used for data signal transmission from the plurality of antennas based on an instruction from a base station device and transmits a data signal using the transmission antenna, wherein the baseband processor determines a timing when a reference signal is transmitted using a standby antenna not used for data signal transmission based on the likelihood of the transmission antenna being switched and transmits the reference signal based on the determined timing.

Abstract: A radio communication system includes transmission/reception devices which perform communication by dynamically switching a first transmission mode and a second transmission mode having a lower quality than the first transmission mode, wherein the transmission/reception devices have a transmission mode decision means which fixes a transmission mode upon communication to the first transmission mode for a given period of time.

Abstract: A mobile station device, which communicates with a base station device, includes a control signal generator that initiates or terminates a cell search based on a reception quality value of a radio wave transmitted from the base station device, and a moving speed of the mobile station device.

Abstract: In a PDI receiver, received signals are digitized by A/D converting portion, correlated by digital matched filters, amplitude of the correlated value is calculated from the correlated output by a correlated value calculating portion, a reproduction clock is generated in accordance with the calculated correlated value by a clock reproducing portion, and the correlated output is demodulated by a differential demodulating portion. Using the clock signal as a reference, a window pulse is generated by a window generating portion, and only during the pulse period, an AND gate is opened, outputs therefrom are integrated by an integrating portion, and data is detected by a detecting portion.

Abstract: The present invention relates to a spread spectrum communication system in which a PN code p(t) is generated from a PN generator, data d(t) is multiplied by the PN code p(t) by a multiplier, and multiplied output is subjected to BPSK modulation by a BPSK modulating block. The PN code p(t) is subjected to BPSK modulation at BPSK modulating block, the result is delayed by at least 1 chip of the PN code by a delay block, combined with a modulated signal from BPSK modulating block, converted to an RF signal, and then it is transmitted from an antenna. The signal received by an antenna is amplified by RF amplifier block, converted to an intermediate frequency signal by frequency converting block, split into two, one of the split signals is directly applied to a multiplier, the other is delayed by a delay block, and then these two split signals are multiplied by a multiplier and thus data d(t) is demodulated and output.