摘要:
The base station apparatus according to the present invention places pilot data and transmission power control data independently of each other in a slot based on processing delays and propagation delays required for transmission power control and places slots by providing an offset for the slot locational relationship between the uplink and downlink.
摘要:
Wireless communication equipment for a CDMA cellular wireless system operating FDD communication and TDD communication of a simplified circuit structure reduces interference with a communication channel. A wireless transmitter for an SS-DS CDMA cellular wireless system operating FDD communications and TDD communications includes an FDD pilot channel for outputting pilot channel signals in an FDD band, an FDD control channel for outputting control channel signals in the FDD band, FDD communications channels for outputting communications channel signals in the FDD band, a TDD pilot channel for outputting pilot channel signals in a TDD band, and a TDD communications channel for outputting communication channel signals in the TDD band. The wireless transmitter does not have a TDD control channel for outputting control channel signals in the TDD band. Control channel signals are transmitted only in the FDD band.
摘要:
A CDMA communication system comprises: N antennas, arranged for space diversity receiving, for receiving a CDMA direct conversion radio wave signal including data to respectively generate N reception CDMA signals; a searching circuit for searching a phase of PN code in one of the N reception CDMA signals; N phase tracking circuits having N correlation detectors for tracking phases of the PN codes in the N reception CDMA signals in accordance with the searched phase to generate phase information of the PN codes, respectively; N de-spreading circuits for de-spreading the N received CDMA direct conversion signals in accordance with the phase information, respectively; and a diversity combining circuit for combining outputs of the N de-spreading circuits to provide the space diversity receiving to output the combined signal. A switch may be further provided for successively selecting one of the N reception CDMA signals periodically and supplying one of the N reception CDMA direct conversion signals to the searching circuit. The phase information is generated in various ways. For example, the larger amounts of in-phase points than a reference are used.
摘要:
First and second phase control amount tables output to first and second vector multiply circuits phase control signals Sc1 and Sc2 representative of corresponding phase shift amounts with gains represented by input gain control signals Sg1 and Sg2 as arguments. The first and second vector multiply circuits shift the phases of in-phase components S13 and S23 and quadrature components S14 and S24 of an antenna 2 in opposite directions in accordance with the phase control signals Sc1 and Sc2. Consequently, the amount of phase shift caused by receiving amplifiers is corrected so that the phase difference at antenna terminals between the input signals to the antennas is maintained.
摘要:
A synchronizing method and circuit accurately and stably operates a direct spread spectrum multiple access communication system. A signal transmitted by modulating the spreading code with data at the transmission side is sampled by a signal of n times (n: 1 or larger integer) the clock speed of the spread spectrum signal at the reception side, and the correlation is detected by a digital matched filter. Consequently, the detection output in every sample in the symbol period is compared with the envelope detection output determined in every sampling period, and the sample positions for a specific number of determined samples are stored in the descending order of the output. The number of times of storage of large sample positions in the stored detection output is counted in every symbol period, and the position of the largest number of storage times is detected as the peak position. From this peak position, capturing or holding the symbol period, and setting of the reception window position results.
摘要:
An error detection method used for digital communication which intends to reduce the probability of outputting the speech obtained by decoding the data that includes an error. The speech data encoded in an error detection code and an error correction code is transmitted. On a receiving side, the data with an error detected in either one of decoding of the error correction code and CRC checking is interpolated so that it is possible to prevent the data which actually includes an error from being decoded into speech as it is.
摘要:
The CM controller 101 outputs times at which signals are sent to various communication terminal apparatuses in a compressed mode based on information on the compressed mode sent from a host station such as a control station apparatus to the scheduler 102, coder 105 and modulator 106. The scheduler 102 decides times (order) at which packet data is sent to the respective communication terminal apparatuses based on priority information such as channel conditions and times at which signals are sent in the compressed mode and outputs schedule information indicating the times for creating this packet data to the switch circuit 104. The switch circuit 104 outputs the packet data to be sent to the communication terminal apparatuses sequentially to the coder 105 according to the schedule created by the scheduler 102.
摘要:
A radio communication apparatus, base station apparatus and communication terminal apparatus capable of predicting an accurate transmission rate before starting data communications to know download time and the like. In the apparatus, a packet CH demodulation section (103) demodulates received packet data. A pilot CH demodulation section (104) demodulates a received signal of a pilot channel. A reception state measuring section (105) measures the SIR from the received signal of the pilot channel. A transmission rate candidate selecting section (106) stores a calculation expression that associates CQI with SIR, and selects CQI by the calculation expression using the measured SIR. A transmission rate predicting section (108) averages selected CQI for a predetermined time to output a transmission rate prediction value. A transmission rate prediction control section (110) outputs information of the transmission rate prediction value to a display section (111) when detecting a key input. The display section (111) displays the transmission rate prediction value on a liquid crystal screen.
摘要:
Transmission diversity and adaptive array antenna transmission is executed with respect to a user to which a shared channel is assigned, or a pilot channel is shared a like a shared channel. By this means it is made possible to secure a large number of users without code resource shortages even where adaptive array antenna is applied to a shared channel.
摘要:
A radio communication apparatus, base station apparatus and communication terminal apparatus capable of predicting an accurate transmission rate before starting data communications to know download time and the like. In the apparatus, a packet CH demodulation section (103) demodulates received packet data. A pilot CH demodulation section (104) demodulates a received signal of a pilot channel. A reception state measuring section (105) measures the SIR from the received signal of the pilot channel. A transmission rate candidate selecting section (106) stores a calculation expression that associates CQI with SIR, and selects CQI by the calculation expression using the measured SIR. A transmission rate predicting section (108) averages selected CQI for a predetermined time to output a transmission rate prediction value. A transmission rate prediction control section (110) outputs information of the transmission rate prediction value to a display section (111) when detecting a key input. The display section (111) displays the transmission rate prediction value on a liquid crystal screen.