Digital downconversion and fast channel selection of narrowband signals using a wide band rf tuner

A wide band receiver to select and demodulate an input signal with single scan spectrum sensing, by performing filtering on said input signal in a digital domain to achieve improved selectivity and sensitivity, said wide band receiver comprising:

• a wide band tuner that down converts said input signal to an intermediate frequency (IF) signal, wherein said input signal is at least one of a wide band radio frequency (RF) signal or a plurality of narrowband RF signals within said wide band RF signal, wherein said wide band tuner selects said plurality of narrowband RF signals using said single scan spectrum sensing, wherein said plurality of narrowband RF signals are down converted to a plurality of IF signals;
• an analog to digital converter (ADC) that converts said plurality of IF signals to a plurality of digital signals;
• a filter that rejects out-of-band signals from said plurality of digital signals to achieve said improved selectivity;
• a Numeric Controlled Oscillator (NCO) that selects at least one narrowband digital signal from said plurality of digital signals based on a phase value obtained from a spectrum selection control unit;
• and
• a demodulator that demodulates said at least one narrowband digital signal based on said phase value to obtain a demodulated digital signal.

A method of performing a digital downconversion and fast channel selection of a plurality of narrowband signals from an input signal with single scan spectrum sensing and thus reducing channel change times in a receiver, said method comprising:

• (i) down converting said plurality of narrowband signals to a plurality of intermediate frequency (IF) signals, wherein a tuner selects said plurality of narrowband RF signals using said single scan spectrum sensing;
• (ii) converting said plurality of IF signals to a plurality of digital signals;
• (iii) filtering out-of-band signals from said plurality of digital signals to achieve an improved selectivity;
• (iv) selecting at least one narrowband digital signal from said plurality of digital signals based on a phase value obtained from a spectrum selection control unit;
• and
• (v) demodulating said at least one narrowband digital signal to obtain a demodulated digital signal, wherein a radio frequency (RF) gain of said receiver is controlled based on an energy measurement of an in-band signal and said out-of-band signals from said plurality of digital signals.