Transmitter/Receiver apparatus

Claim 2

A transmitter/receiver apparatus comprising: a local oscillator for generating a local oscillation frequency at a predetermined position between a transmit and a receive frequency band; a transmit frequency converter for converting a transmit intermediate frequency band into said transmit frequency band based on said local oscillation frequency such that a transmit image frequency band of said transmit frequency band does not overlap said receive frequency band; and a receive frequency converter for converting, based on the local oscillation frequency, the receive frequency band into a receive intermediate frequency band, which does not overlap the transmit intermediate frequency band, such that a receive image frequency band of said receive intermediate frequency band does not overlap the transmit frequency band.

Claim 3

A transmitter/receiver apparatus as claimed in claim l, further comprising a first frequency multiplexer which connects to the transmit and receive frequency converters one end of a single signal cable over which a signal of the transmit intermediate frequency band and a signal of the receive intermediate frequency band are propagated in a frequency-multiplexed condition.

Claim 4

A transmitter/receiver apparatus as claimed in claim 2, further comprising a second frequency multiplexer which is connected to the other end of the signal cable.

Claim 5

A transmitter/receiver apparatus as claimed in claim 2 or 3, wherein the signal cable comprises a coaxial cable.

Claim 6

A transmitter/receiver apparatus comprising a first and a second device which are interconnected by a single signal cable; said first device comprising: a local oscillator for generating a local oscillation frequency at a predetermined position between a transmit and a receive frequency band; a transmit frequency converter for converting a transmit intermediate frequency band into said transmit frequency band based on said local oscillation frequency such that a transmit image frequency band of said transmit frequency band does not overlap said receive frequency band; a receive frequency converter for converting, based on the local oscillation frequency, the receive frequency band into a receive intermediate frequency band, which does not overlap the transmit intermediate frequency band, such that a receive image frequency band of said receive intermediate frequency band does not overlap the transmit frequency band; and a first frequency multiplexer connected between one end of the signal cable and said transmit and receive frequency converters for multiplexing in frequency a signal of the transmit intermediate frequency band and a signal of the receive intermediate frequency band; and said second device comprising: a second frequency multiplexer connected to the other end of said signal cable; and a demodulator and a modulator each being connected to a respective one of other two terminals of said second frequency multiplexer.

Claim 7

A transmitter/receiver apparatus comprising a first and a second device which are interconnected by a single signal cable; said first device comprising: a local oscillator for generating a local oscillation frequency at a predetermined position between a transmit and a receive frequency band; a transmit frequency converter for converting a transmit intermediate frequency band into said transmit frequency band based on said local oscillation frequency such that a transmit image frequency band of said transmit frequency band does not overlap said receive frequency band; a receive frequency converter for converting, based on the local oscillation frequency, the receive frequency band into a receive intermediate frequency band, which does not overlap the transmit intermediate frequency band, such that a receive image frequency band of said receive intermediate frequency band does not overlap the transmit frequency band; and a first frequency multiplexer connected between one end of the signal cable and said transmit and receive frequency converters for multiplexing in frequency a signal of the transmit intermediate frequency band and a signal of the receive intermediate frequency band; and said second device comprising: a second frequency multiplexer connected to the other end of said signal cable; and a demodulator and a modulator each being connected to a respective one of other two terminals of said second frequency multiplexer.

Claim 8

A transmitter/receiver apparatus as claimed in claim 5, wherein the first device is located outside of a building and the second device inside of said building.

Claim 9

A transmitter/receiver apparatus as claimed in claim 5 or 6, wherein the first device is mounted in a feeder section of an antenna.

Claim 10

A transmitter/receiver apparatus as claimed in any of claims 5 to 7, wherein the signal cable comprises a coaxial cable.