Low intermediate frequency receiver
View Patent ↗One embodiment relates to a low intermediate frequency (IF) receiver. The low-IF receiver includes an analog front end that is configured to receive a modulated IQ data signal and provide an in-phase signal and a quadrature signal, where the in-phase signal is phase shifted by approximately 90° relative to the quadrature signal. The low-IF receiver further includes a digital processing block, and a single path that provides only one of the in-phase signal and the quadrature signal to the digital processing block. Other receivers and methods are also disclosed.
1. A low intermediate frequency (IF) receiver, comprising:
an analog front end that is configured to receive a modulated IQ data signal and provide an in-phase signal and a quadrature signal, where the in-phase signal is phase shifted by approximately 90° relative to the quadrature signal;
a single path that provides only one of the in-phase signal and the quadrature signal to a digital processing block; and
wherein the digital processing block comprises: first and second digital mixers that each receive the same one signal from the single path, wherein the first digital mixer processes the one signal as a function of a first oscillator signal and wherein the second digital mixer processes the one signal as a function of a second oscillator signal that is approximately 90° phase shifted with respect to the first oscillator signal.
2. The receiver of claim 1 , further comprising:
a filtering block that filters at least one, if not both, of: the in-phase signal and the quadrature signal; and which the filtering block provides filtered signals to the digital processing block.
3. The receiver of claim 1 , wherein the one signal is a digitally encoded signal and wherein the first digital mixer processes the digitally encoded signal as a function of a first numerically controlled oscillator signal and where the second mixer processes the digitally encoded signal as a function of a second numerically controlled oscillator signal that is phase shifted by about 90 degrees relative to the first numerically controlled oscillator signal.
4. The receiver of claim 1 , where the analog front end further comprises:
a first mixer for providing the in-phase signal as a function of the modulated IQ data signal and a first local oscillator signal; and
a second mixer for providing the quadrature signal as a function of the modulated IQ data signal and a second local oscillator signal that is phase shifted by approximately 90° relative to the first local oscillator signal.
5. The receiver of claim 1 wherein the single path carries the quadrature signal and not the in-phase signal.
6. The receiver of claim 5 , wherein the receiver is devoid of circuitry for processing the in-phase signal.
7. The receiver of claim 1 , wherein the one signal has the same phase when received by the first and the second digital mixers.