Patent
Low leakage local oscillator system
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TLDR
In this paper, a first frequency divider divides the frequency of the local oscillator signal by a first division factor to produce a conversion signal, where the conversion means responsive to the conversion signal converts between said communication signal and base-band signal.Abstract:
Local oscillator apparatus comprising communication signal terminals for a communication signal, especially in a receiver or a transmitter, and a controlled frequency oscillator for producing a local oscillator signal. The local oscillator also includes a reference frequency generator and a feedback loop for selecting and adjusting the frequency of the local oscillator signal relative to the frequency of said reference frequency signal. A first frequency divider divides the frequency of the local oscillator signal by a first division factor to produce a conversion signal, where the frequency of said conversion signal is at least approximately equal to the frequency of the communication signal, and conversion means responsive to the conversion signal converts between said communication signal and base-band signal. A second frequency divider divides the frequency of the local oscillator signal by a second division factor and is connected in the feedback loop, where the division factor is different to the second division factor and the ratios between said first and second division factors are fractional.read more
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References
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Patent
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