Patent ID: 7006802

Claim:
A universal transmitter, comprising: an input circuit including an antenna, a central processing unit (CPU) coupled to the input circuit, and a radio frequency (RF) circuit coupled to the CPU; said CPU to generate a plurality of discrete digital outputs; said RF circuit, in response to the plurality of discrete digital outputs, to generate and transmit a local RF signal at a scanning frequency; said input circuit to receive the local RF signal and a template RF signal including a target frequency and a modulation pattern, and to mix the local RF signal and the template RF signal and provide a mixed signal; and said CPU to (i) incrementally increase the scanning frequency of the local RF signal by a first predetermined amount, starting from a lower scanning frequency, until a magnitude of the mixed signal, above a lower threshold value, is detected, (ii) incrementally increase the scanning frequency of the local RF signal by a second predetermined amount until the magnitude of the mixed signal falls to or below the lower threshold value, (iii) store the current scanning frequency as a first frequency; (iv) increase the scanning frequency by a third predetermined amount; (v) incrementally decrease the scanning frequency by a fourth predetermined increments until the magnitude of the mixed signal falls to or below the lower threshold value; (vi) store the current scanning frequency as a second frequency, and (vii) determine the target frequency as being between the first and second frequencies.