COMMUNICATION SYSTEM, FREQUENCY CONTROL METHOD, REMOTE TERMINAL AND NON-TRANSITORY COMPUTER-READABLE RECORDING MEDIUM HAVING STORED THEREIN PROGRAM

摘要

A wireless-device-end communicator transmits, to a remote-end communicator, an IF signal and a wireless-device-end AF signal, the wireless-device-end AF signal being generated by demodulating the IF signal on a basis of a wireless-device-end local frequency. A remote-end controller starts a tuning mode when an instruction obtainer obtains the start instruction for the tuning mode, and adjusts a remote-end local frequency in accordance with the obtained adjustment instruction. A remote end demodulator demodulates the received IF signal on a basis of the remote-end local frequency, and outputs a remote-end AF signal. An outputter outputs the remote-end AF signal in the tuning mode, and outputs the wireless-device-end AF signal in a normal mode. At an end of the tuning mode, the wireless-device-end local frequency is adjusted in such a way that the reception frequency of a wireless device becomes consistent with the reception frequency indicated by the last adjustment instruction.

主权项

1. A communication system comprising a wireless device and a remote terminal connected to the wireless device via a communication network, and including a tuning mode for a tuning operation, wherein:
the wireless device comprises: a frequency converter to perform, on a basis of a wireless-device-end local frequency, a frequency conversion on a reception signal on a basis of a radio wave captured by an antenna, and output an IF signal that is an intermediate frequency signal; a wireless-device-end demodulator to demodulate the IF signal, and output a wireless-device-end AF signal that is the demodulated signal; a wireless-device-end communicator to transmit the IF signal and the wireless-device-end AF signal to the remote terminal, and exchange a control signal with the remote terminal; and a wireless-device-end controller to adjust the wireless-device-end local frequency, the remote terminal comprises: an instruction obtainer to obtain an adjustment instruction of a reception frequency; a remote-end communicator to receive the IF signal and the wireless-device-end AF signal from the wireless device, and exchange a control signal with the wireless device; a remote-end demodulator to demodulate the received IF signal on a basis of a remote-end local frequency, and output a remote-end AF signal that is the demodulated signal; a remote-end controller to adjust the remote-end local frequency in accordance with the adjustment instruction obtained by the instruction obtainer in the tuning mode; and an outputter to output the remote-end AF signal output by the remote-end demodulator in the tuning mode, and output the wireless-device-end AF signal received by the remote-end communicator in a mode other than the tuning mode, wherein: the remote-end communicator is to transmit the control signal representing the last adjustment instruction at an end of the tuning mode, and when the wireless-device-end communicator receives the control signal representing the last adjustment instruction, the wireless-device-end controller is to adjust the wireless-device-end local frequency in accordance with the last adjustment instruction.