Dual mode radio frequency receivers for wideband signal processing

A method comprising;

• processing a received RF signal using an electronic circuit to generate an output signal, the output signal being generated via an RF processing circuit and a programmable quadrature demodulator block operable in a first mode and a second mode, wherein
• the RF processing circuit processes the received RF signals to generate a processed RF output signal and comprises:
• a plurality of first filters, each first filter being at least one of a low pass filter, high pass filter, and a bandpass filter and characterized by at least a predetermined 3dB cut-off frequency;
• a plurality of second filters, each second filter being a characterized by a predetermined 3dB cut-off frequency;
• and
• a switching circuit to selectively couple the received RF signal to a predetermined first filter of the plurality of first filters and then a predetermined second filter of the plurality of second filters prior to the received RF signal is coupled to portion of the electronic circuit comprising the pair of mixers;
• and
• the programmable quadrature demodulator block comprises a pair of mixers each receiving a local oscillator signal with a predetermined phase offset between the local oscillator signals applied to the pair of mixers, wherein
• in the first mode of the programmable quadrature demodulator block comprises coupling the processed RF output signal to both mixers and generating first and second outputs representing in-phase and quadrature components of the processed RF output signal respectively;
• and
• in the second mode of the programmable quadrature demodulator block comprises coupling the processed RF output signal to only one mixer of the pair of mixers, generating a down converted signal in dependence upon the processed RF output signal and the local oscillator signal, and selectively blocking output from the other mixer of the pair of mixers.

A device comprising:

• a single RF receiver block supporting operation in a first mode and a second mode comprising at least a programmable quadrature demodulator block operable in the first mode and the second mode for receiving an RF signal and generating an output signal, the programmable quadrature demodulator block comprising a first mixer receiving a local oscillator signal and a second mixer receiving the local oscillator signal with a predetermined phase offset;
• wherein
• in the first mode the programmable quadrature demodulator block couples the RF signal to both first and second mixers and generates first and second outputs representing in-phase and quadrature components of the RF signal;
• and
• in the second mode the programmable quadrature demodulator block couples the RF signal to only the first mixer and generates a down converted output signal.

A method comprising;

• processing a RF signal using an electronic circuit to generate an output signal, the output signal generated via a programmable quadrature demodulator block operable in a first mode and a second mode, the programmable quadrature demodulator block comprising a pair of mixers each receiving a local oscillator signal with a predetermined phase offset between the local oscillator signals applied to the pair of mixers, wherein
• the first mode of the programmable quadrature demodulator block comprises coupling the RF signal to both mixers and generating first and second outputs representing in-phase and quadrature components of the RF signal respectively;
• the second mode of the programmable quadrature demodulator block comprises coupling the RF signal to only one mixer of the pair of mixers and generating a down converted signal in dependence upon the RF signal and the local oscillator signal, and selectively blocking output from the other mixer of the pair of mixers;
• re-configuring the electronic circuit from the second mode to the first mode comprises the steps of selecting an appropriate front-end filter, establishing the local oscillator at a first frequency and decoupling the first mixer of the pair of mixers from the output of the electronic circuit, and determining whether to reconfigure a SAW filter bank to select a different SAW filter than the SAW filter employed in the second mode;
• and
• re-configuring the electronic circuit from the first mode to the second mode comprises the steps of establishing the local oscillator at a second frequency, re-coupling the first mixer of the pair of mixers to the output of the electronic circuit, and selecting an appropriate anti- aliasing filter.

A method comprising:

• processing a received RF signal using an electronic circuit to generate an output signal, the output signal being generated-via an RF processing circuit and a programmable quadrature demodulator block operable in a first mode and a second mode, wherein
• the RF processing circuit processes the received RF signals to generate a processed RF output signal by coupling the received RF signal through a first filter of a plurality of first filters and second filter of a plurality of second filters,
• each first filter of the plurality of first filters is at least one of a low pass filter, a high pass filter, and a bandpass filter exploiting at least one of passive electrical elements and active electrical elements;
• each second filter of the plurality of second filters is a SAW filter;
• and
• the programmable quadrature demodulator block comprises a pair of mixers each receiving a local oscillator signal with a predetermined phase offset between the local oscillator signals applied to the pair of mixers, wherein
• in the first mode of the programmable quadrature demodulator block comprises coupling the processed RF output signal to both mixers and generating first and second outputs representing in-phase and quadrature components of the processed RF output signal respectively;
• and
• in the second mode of the programmable quadrature demodulator block comprises coupling the processed RF output signal to only one mixer of the pair of mixers, generating a down converted signal in dependence upon the processed RF output signal and the local oscillator signal, and selectively blocking output from the other mixer of the pair of mixers.