摘要:
It is possible to cope with a change of the transmitting capacity in wireless communication such as wireless telephone system. A plurality of transmission channels are set within the transmission frequency band prepared for each base station. When a communication is made between the terminal equipment and the base station through the transmission channels, at least a first transmission channel and a second transmission channel are set as the transmission channel depending on a class of information to be transmitted. The first transmission channel is set to have a fixed transmitting capacity and the second transmission channel is set so that the minimum transmitting capacity may be defined and the transmitting capacity greater than the minimum transmitting capacity may be set depending on the setting condition of the transmission channels within the transmission frequency band prepared.
摘要:
While the phase of a PN code is being shifted every a predetermined number of chips, correlation values with a received code are obtained. At this point, de-spread signal levels are cumulated and correlation values are obtained. At this point, a threshold value generating circuit generates a threshold value corresponding to the cumulated value of the de-spread signal levels. In other words, as the number of additions increases, the threshold value is increased. Alternatively, the number of additions is normalized and compared with the threshold value. When the cumulated value does not exceed a predetermined threshold value, since the correlation is weak, the current phase is immediately shifted to the next phase.
摘要:
In a GPS receiver and a portable communication apparatus according to this invention, demodulation timing of the GPS received signal received from a satellite in the global positioning system is controlled in accordance with transmission timing of transmitting the CDMA transmission signal to a base station in a predetermined communication system, so that the GPS received signal can be accurately demodulated, preventing radio waves which occur during transmission of the CDMA transmission signal from interfering with the GPS received signal. Thus, the GPS received signal can be demodulated without deterioration of reception quality.
摘要:
A synthesis signal which was reproduced from a reproducing apparatus and converted into an analog signal includes an analog information signal and a copy control code. The copy control code is modulated by a spread spectrum. A code reading unit of the recording apparatus extracts a copy control code by an inverse spread spectrum. A code changing unit changes the copy control code by a spread spectrum as necessary. An output signal of the code changing unit is converted into a digital signal. The digital signal is subjected to processes necessary for recording and is recorded to a recording medium.
摘要:
It is possible to cope with a change of the transmitting capacity in wireless communication such as wireless telephone system. A plurality of transmission channels are set within the transmission frequency band prepared for each base station. When a communication is made between the terminal equipment and the base station through the transmission channels, at least a first transmission channel and a second transmission channel are set as the transmission channel depending on a class of information to be transmitted. The first transmission channel is set to have a fixed transmitting capacity and the second transmission channel is set so that the minimum transmitting capacity may be defined and the transmitting capacity greater than the minimum transmitting capacity may be set depending on the setting condition of the transmission channels within the transmission frequency band prepared.
摘要:
The object of the present invention is to insure the communication quality best suited to the type of data between the transmission system and the receiver. In the wireless communication system 1 for controlling the data communication quality between the transmission system 2 to transmit contents and the mobile wireless terminal 8 to receive contents from said transmission system 2 via the predetermined communication path 15, since the transmission system 2 changes the modulation system in the data output unit 13 corresponding to the type of contents to be transmitted to the mobile wireless terminal 8, the data communication quality between said transmission system 2 and the mobile wireless.terminal 8 can be controlled. Thereby, the data transmission from the transmission system 2 to the mobile wireless terminal 8 can be executed according to the modulation system best suited to the type of contents holding the predetermined communication quality.
摘要:
The object of the present invention is to insure the communication quality best suited to the type of data between the transmission system and the receiver. In the wireless communication system 1 for controlling the data communication quality between the transmission system 2 to transmit contents and the mobile wireless terminal 8 to receive contents from said transmission system 2 via the predetermined communication path 15, since the transmission system 2 changes the modulation system in the data output unit 13 corresponding to the type of contents to be transmitted to the mobile wireless terminal 8, the data communication quality between said transmission system 2 and the mobile wireless terminal 8 can be controlled. Thereby, the data transmission from the transmission system 2 to the mobile wireless terminal 8 can be executed according to the modulation system best suited to the type of contents holding the predetermined communication quality.
摘要:
While the phase of a PN code is being shifted every a predetermined number of chips, correlation values with a received code are obtained. A plurality of the largest correlation values are selected from those that have been detected and designated to fingers. When a correlation value is obtained for each phase, the maximum value of the correlation values that have been detected is detected by a maximum value detecting circuit. The maximum value is stored in a maximum value memory. When a plurality of the largest correlation values are selected, the maximum value that has been stored in the maximum value memory is used.
摘要:
A next alternative storing memory that stores a next alternative code is disposed. When demodulated data cannot be obtained, in the case that a code as a next alternative has been stored in the next alternative storing memory, a partial searching process is performed with the code so as to demodulate data. When data can be demodulated, a searching process is performed with the code.