Two-way radio communication system and two-way radio communication method

A two-way radio communication system for two-way communication between first and second radio stations, the two-way radio communication system comprising first and second radio stations, each of which radio stations are equipped with a signal modulator for generating a modulated signal in an intermediate frequency band that is lower than a radio frequency;

• a modulated transmission signal generator that produces a modulated radio transmission signal by using a local oscillation signal to up-convert the modulated signal to a radio frequency band;
• a transmitter that transmits the local oscillation signal used by the modulated transmission signal generator together with the modulated radio transmission signal as a radio signal;
• and
• a receiver that receives a radio signal from the other radio station and down-converts the received signal to a modulated intermediate frequency band by generating a multiplication component of a modulated radio signal component and local oscillation signal component received from the other radio station.

A two-way radio communication system for two-way communication between first and second radio stations, the two-way radio communication system comprising:

• a first radio station equipped with a signal modulator for generating a modulated signal in an intermediate frequency band that is lower than a radio frequency;
• a modulated radio signal generator that uses a local oscillation signal to up-convert the modulated signal to a radio frequency band;
• a transmitter that from among sideband signals generated during conversion of a modulated intermediate frequency band signal to the radio frequency band by the modulated radio signal generator, selects an upper-side-band signal as a radio signal and transmits the selected radio signal together with the local oscillation signal utilized by the modulated radio signal generator;
• and
• a receiver that receives a radio signal from the second radio station and down-converts the received signal to a modulated intermediate frequency band by generating a multiplication component of a modulated radio signal component and local oscillation signal component received from the other radio station;
• a second radio station equipped with a signal modulator for generating a modulated signal in an intermediate frequency band that is lower than a radio frequency;
• a modulated radio signal generator that uses a local oscillation signal to up-convert the modulated signal to a radio frequency band;
• a transmitter that from among sideband signals generated during conversion of a modulated intermediate frequency band signal to the radio frequency band by the modulated radio signal generator, selects a lower-sideband signal as a radio signal and transmits the selected radio signal together with the local oscillation signal utilized by the modulated radio signal generator;
• and
• a receiver that receives a radio signal from the first radio station and down-converts the received signal to a modulated intermediate frequency band by generating a multiplication component of a modulated radio signal component and local oscillation signal component received from the first radio station.

A two-way radio communication method for conducting two-way communication between first and second radio stations, the two-way radio communication method comprising:

• a first radio station that transmits a radio signal to a second radio station by generating a modulated signal in an intermediate frequency band that is lower than a radio frequency, producing a modulated radio transmission signal, using a local oscillation signal to up-convert the modulated signal to a radio frequency band and transmitting the local oscillation signal used by the modulated radio transmission signal with the modulated radio transmission signal as a radio signal;
• and when receiving a radio signal from the second radio station, down-converts the received signal to a modulated frequency band by using the local oscillation signal utilized for up-conversion;
• and
• a second radio station that extracts and regenerates local oscillation components from among signal components received from the first radio station, uses a local oscillation signal thus regenerated to down-convert a received modulated radio signal to an intermediate frequency band and, when transmitting a radio signal to the first radio station, produces a modulated signal in an intermediate frequency band that is lower than a radio frequency, and uses the regenerated local oscillation signal to up-convert to a radio frequency band a modulated signal produced by the signal modulator.

A two-way radio communication method for conducting two-way communication between first and second radio stations, the two-way radio communication method comprising transmission by a first radio station of a radio signal to a second radio station by generating a modulated signal in an intermediate frequency band that is lower than a radio frequency, producing a modulated radio transmission signal, using a local oscillation signal to up-convert the modulated signal to a radio frequency band and transmitting the local oscillation signal used by the modulated radio transmission signal with the modulated radio transmission signal as a radio signal;

• and when receiving a radio signal from the second radio station, down-converts the received signal to a modulated frequency band by using the local oscillation signal utilized for up conversion and, of sideband signals generated during conversion of a modulated intermediate frequency band signal to the radio frequency band, selects an upper-side-band radio signal and transmits the selected radio signal together with the local oscillation signal utilized by a modulated radio signal generator, and when a radio signal is received from the other radio station, down-converts the received signal to a modulated intermediate frequency band by generating a multiplication component of a received modulated radio signal component and local oscillation signal component;
• and transmission to the first radio station by a second radio station, generating a modulated signal in an intermediate frequency band that is lower than a radio frequency, producing a modulated radio transmission signal, using a local oscillation signal to up-convert the modulated signal to a radio frequency band and, of sideband signals generated during conversion of a modulated intermediate frequency band signal to the radio frequency band by the modulated radio signal generator, selecting a lower-side-band radio signal and transmitting the selected radio signal together with the local oscillation signal, and when a radio signal is received from the first radio station, down-converting the received signal to a modulated intermediate frequency band by generating a multiplication component of a received modulated radio signal component and local oscillation signal component.