Frequency synthesizer module for dual band radio
First Claim
1. A frequency synthesizer module with temperature compensation, comprising:
- a crystal in a crystal oscillator circuit with a frequency that is controllable by a coupled varactor;
a memory containing information characterizing a temperature dependency of the crystal, the information being applied to the varactor to compensate for changes in the frequency of the crystal in response to a signal from a coupled temperature sensor; and
at least one locked loop circuit chosen from the group consisting of a phase locked loop, a frequency locked loop and a delay locked loop, the at least one locked loop circuit includes a loop filter, at least one associated frequency divider, and a switchable dual band voltage controlled oscillator;
the crystal oscillator circuit being coupled to the at least one locked loop circuit and the frequency of the crystal oscillator circuit being controlled by the memory via the varactor such that a temperature compensated frequency is provided to the locked loop circuit thereby providing a stable output frequency from the module.
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Accused Products
Abstract
A frequency synthesizer module with temperature compensation of a crystal oscillator circuit frequency controlled by a varactor. A module memory contains information characterizing a temperature dependency of a crystal which is applied to the varactor to temperature compensate the crystal in response to a temperature sensor signal. The module includes at least one locked loop circuit including a loop filter, at least one associated frequency divider, and a switchable dual band voltage controlled oscillator. The crystal oscillator is coupled to the at least one locked loop circuit and the frequency of the crystal is controlled by the memory via the varactor such that a temperature compensated output frequency is provided by the module.
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Citations
18 Claims
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1. A frequency synthesizer module with temperature compensation, comprising:
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a crystal in a crystal oscillator circuit with a frequency that is controllable by a coupled varactor; a memory containing information characterizing a temperature dependency of the crystal, the information being applied to the varactor to compensate for changes in the frequency of the crystal in response to a signal from a coupled temperature sensor; and at least one locked loop circuit chosen from the group consisting of a phase locked loop, a frequency locked loop and a delay locked loop, the at least one locked loop circuit includes a loop filter, at least one associated frequency divider, and a switchable dual band voltage controlled oscillator; the crystal oscillator circuit being coupled to the at least one locked loop circuit and the frequency of the crystal oscillator circuit being controlled by the memory via the varactor such that a temperature compensated frequency is provided to the locked loop circuit thereby providing a stable output frequency from the module. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. A dual band frequency synthesizer module with temperature compensation, comprising:
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a crystal in a crystal oscillator circuit with a frequency that is controllable by a coupled varactor; a memory containing information characterizing a temperature dependency of the crystal, the information being applied to the varactor to compensate for changes in the frequency of the crystal in response to a signal from a coupled temperature sensor; an IF phase locked loop circuit and an RF phase locked loop circuit with a loop filter and a voltage controlled oscillator, each phase locked loop circuit including an associated frequency divider; and a digital data bus which controls all of;
a nominal operating frequency of the crystal oscillator circuit, the divider of each phase locked loop circuit, the information in the memory, and switching of the dual band voltage controlled oscillator;the crystal oscillator circuit being coupled to the phase locked loop circuits and the frequency of the crystal oscillator circuit being controlled by the memory via the varactor such that a temperature compensated frequency is provided to the phase locked loop circuits thereby providing a stable output frequency from the module. - View Dependent Claims (9, 10, 11, 12, 13)
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14. A radio communication device having an antenna feeding receiver and transmitter circuit through a duplexer, the radio communication device including RF and IF modulation and demodulation circuits and a frequency synthesizer module with temperature compensation, the frequency synthesizer module comprising:
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a crystal in a crystal oscillator circuit with a frequency that is controllable by a coupled varactor; a memory containing information characterizing a temperature dependency of the crystal, the information being applied to the varactor to compensate for changes in the frequency of the crystal in response to a signal from a coupled temperature sensor; and at least one locked loop circuit chosen from the group consisting of a phase locked loop, a frequency locked loop and a delay locked loop, the at least one locked loop circuit includes a loop filter, at least one associated frequency divider, and a switchable dual band voltage controlled oscillator; the crystal oscillator circuit being coupled to the at least one locked loop circuit and the frequency of the crystal oscillator circuit being controlled by the memory via the varactor such that a temperature compensated frequency is provided to the locked loop circuit thereby providing a stable output frequencies from the module to receiver and transmitter RF mixers and to IF circuits in the radio communication device. - View Dependent Claims (15, 16, 17, 18)
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Specification