US 6,415,001 B1 · System and process for shared frequency source multi-band transmitters and receivers

Abstract

A communication system for communicating RF signals at any one of a plurality of communication standards through a common antenna is disclosed. The communication system comprises a transmitting unit, a receiving unit, an IF LO frequency generator, an RF LO frequency generator, a reference source, and an antenna. The transmitting unit has a transmit RF information signal output, a modulator for transforming a transmit baseband information signal into a modulated transmit IF information signal, and an upconverter for upconverting the transmit IF information signal into a transmit RF information signal. The receiving unit has a receive RF information signal input, a first downconverter for downconverting a receive RF information signal to a first receive IF information signal, a second downconverter for downconverting the first receive IF information signal to a second receive IF information signal, an analog-to-digital converter for converting the second receive IF information signal to a receive digital information signal, and a digital signal processor for digitally filtering the receive digital information signal. By selecting expedient IF LOs and RF LOs, the IF LO and RF LO frequency generators can be shared between the transmitting and receiving units, and transmit and receive filters can be shared between different communication standards.

Claims31

Dependent claims

A communication system for communicating RF signals at any one of a plurality of communication standards through a common antenna, each communication standard having a unique transmit band, receive band, and a common data rate, the communication system comprising:

a transmitting unit having a transmit RF information signal output, the transmitting unit having a modulator for transforming a transmit baseband information signal into a modulated transmit IF information signal and an upconverter for upconverting the transmit IF information signal into a transmit RF information signal;
a receiving unit having a receive RF information signal input, the receiving unit having a first downconverter for downconverting a receive RF information signal to a first receive IF information signal, a second downconverter for downconverting the first receive IF information signal to a second receive IF information signal, an analog-to-digital converter for converting the second receive IF information signal to a receive digital information signal, and a digital signal processor for processing the receive digital information signal;
and
an antenna coupled to the transmit RF information signal output and the receive RF information signal input for transmitting and receiving RF information signals;
wherein the digital signal processor uses a processing clock greater than or equal to about four times the data rate, the analog-to-digital converter operates at a sample rate selected such that no odd-order harmonic of one fourth of the sample rate substantially coincides with any harmonic of the processing clock, and the second IF carrier frequency for the second receive IF information signal is selected to be an odd-order harmonic of one fourth of the sample rate.

2 more elements

A process for communicating RF signals at any one of a plurality of communication standards through a common antenna, each communication standard having a unique transmit band, receive band, and a common data rate, the process comprising:

transforming a transmit baseband information signal into a modulated transmit IF information signal, upconverting the transmit IF information signal into a transmit RF information signal, and transmitting the transmit RF information signal through the antenna;
receiving a receive RF information signal from the antenna, downconverting the receive RF information signal to a first receive IF information signal, and downconverting the first receive IF information signal to a second receive IF information signal;
converting the second receive IF information signal to a receive digital information signal at a sample rate and digitally filtering the receive digital information signal using a processing clock greater than or equal to about four times the data rate, the sample rate being selected such that no odd-order harmonic of one fourth of the sample rate substantially coincides with any harmonic of the processing clock;
and
selecting a second IF carrier frequency for the second receive IF information signal to be an odd-order harmonic of one fourth of the sample rate.

2 more elements

means for transforming a transmit baseband information signal into a modulated transmit IF information signal, upconverting the transmit IF information signal into a transmit RF information signal, and transmitting the transmit RF information signal through the antenna;
means for receiving a receive RF information signal from the antenna, downconverting the receive RF information signal to a first receive IF information signal, and downconverting the first receive IF information signal to a second receive IF information signal;
means for converting the second receive IF information signal to a receive digital information signal at a sample rate and digitally filtering the receive digital information signal using a processing clock greater than or equal to about four times the data rate, the sample rate being selected such that no odd-order harmonic of one fourth of the sample rate substantially coincides with any harmonic of the processing clock;
and
means for selecting a second IF carrier frequency for the second receive IF information signal to be an odd-order harmonic of one fourth of the sample rate.

2 more elements

Dependencies are inferred from the claim text.

System and process for shared frequency source multi-band transmitters and receivers

Life of this patent

System and process for shared frequency source multi-band transmitters and receivers

Life of this patent

Abstract

Claims31