Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
145 words
In a system including a global positioning system (GPS) receiver and a signal receiver coupled thereto, a method of synthesizing a reference signal of a desired frequency within the signal receiver, comprising the steps of: generating timing signals within the GPS receiver on the basis of GPS satellite signals received thereby, and providing the timing signals to the signal receiver in an open loop arrangement, wherein the timing signals are separated by known time intervals; and in the signal receiver, counting cycles of the local oscillator occurring between ones of the timing signals to produce a count value indicative of the local oscillator's frequency, and synthesizing a reference signal for use by the signal receiver, the synthesizing step including calibrating a frequency synthesizer driven by the local oscillator in accordance with the count value so as to synthesize the reference signal at a desired frequency.
Claim 2
Dependent Claim
145 words
In a system including a global positioning system (GPS) receiver and a signal receiver coupled thereto, a method of synthesizing a reference signal of a desired frequency within the signal receiver, comprising the steps of: generating timing signals within the GPS receiver on the basis of GPS satellite signals received thereby, and providing the timing signals to the signal receiver in an open loop arrangement, wherein the timing signals are separated by known time intervals; and in the signal receiver, counting cycles of the local oscillator occurring between ones of the timing signals to produce a count value indicative of the local oscillator's frequency, and synthesizing a reference signal for use by the signal receiver, the synthesizing step including calibrating a frequency synthesizer driven by the local oscillator in accordance with the count value so as to synthesize the reference signal at a desired frequency.
Claim 3
Dependent Claim
18 words
The method of claim 1, wherein the timing signals are generated at the rate of one per second.
Claim 4
Dependent Claim
45 words
The method of claim 1, further including the steps of: while using the reference signal to tune the signal receiver, receiving at the signal receiver differential GPS correction signals; and communicating correction information to the GPS receiver corresponding to the received differential GPS correction signals.
Claim 5
Dependent Claim
46 words
The method of claim 1, wherein the signal receiver is a C-band receiver configured to receive differential GPS correction signals from one or more GPS reference stations; the method further including communicating correction information to the GPS receiver corresponding to the received differential GPS correction signals.
Claim 6
Dependent Claim
144 words
A navigation system, comprising: a global positioning system (GPS) receiver, the GPS receiver including signal processing circuitry that generates timing signals on the basis of GPS satellite signals received thereby; a signal receiver having a local oscillator; an open loop link coupling the GPS receiver to the signal receiver; a cycle counter in the signal receiver for counting oscillations of the local oscillator, the cycle counter including a port for receiving the timing signals from the GPS receiver via the open loop link, the cycle counter counting cycles of the local oscillator occurring between ones of the timing signals to produce a count value indicative of the local oscillator's frequency; and a frequency synthesizer, in the signal receiver and driven by the local oscillator, that is calibrated in accordance with the count value so as to synthesize a reference signal at a desired frequency.
Claim 7
Dependent Claim
144 words
A navigation system, comprising: a global positioning system (GPS) receiver, the GPS receiver including signal processing circuitry that generates timing signals on the basis of GPS satellite signals received thereby; a signal receiver having a local oscillator; an open loop link coupling the GPS receiver to the signal receiver; a cycle counter in the signal receiver for counting oscillations of the local oscillator, the cycle counter including a port for receiving the timing signals from the GPS receiver via the open loop link, the cycle counter counting cycles of the local oscillator occurring between ones of the timing signals to produce a count value indicative of the local oscillator's frequency; and a frequency synthesizer, in the signal receiver and driven by the local oscillator, that is calibrated in accordance with the count value so as to synthesize a reference signal at a desired frequency.
Claim 8
Dependent Claim
26 words
The navigation system of claim 5, wherein the signal processing circuitry in the GPS receiver generates the timing signals at the rate of one per second.
Claim 9
Dependent Claim
59 words
The navigation system of claim 5, including: a signal receiving network in the signal receiver that is tuned in accordance with the reference signal and that extracts differential GPS correction signals from signals received by the signal receiving network; and a data link for communicating correction information to the GPS receiver corresponding to the extracted differential GPS correction signals.
Claim 10
Dependent Claim
28 words
The navigation system of claim 5, wherein the signal receiver is a C-band receiver configured to receive differential GPS correction signals from one or more GPS reference stations.