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US 6,788,744 B1Granted
Power control circuit and transmitter
AssigneeFujitsu Limited
InventorAtsuhiro Hirama
Life of this patent
Estimating the term…
Abstract
In a power control circuit according to the present invention, a circuit for making a desired response at a specific level is stationarily fed with a signal at the specific level so that the resultant level deviation is automatically corrected at a stage subsequent to the circuit. Besides, a transmitter according to the present invention is configured with provided a modulator as the above-described circuit. In a system or equipment according to those inventions, without its configuration being changed drastically, the desired characteristics and performances are kept with high accuracy, the cost for the manufacture, maintenance, and running is reduced, and the overall reliability is improved.
Claims10
A power control circuit comprising:
- measuring means for measuring a level Li of an input signal;
- level variant means for amplifying said input signal with a first gain G1 and feeding the amplified input signal to a circuit for making a desired response when fed with a signal at a predetermined level Ls;
- level adjustment means for amplifying an output signal obtained as a response of said circuit with a second gain G2;
- and
- controlling means for setting said first gain G1 to a ratio between said predetermined level Ls and the level Li measured by said measuring means and setting said second gain G2 to a ratio between a level Lt of an output signal to be obtained at an output terminal of said level adjustment means and a product of said predetermined level Ls and a gain g of said circuit in a condition for making said desired response,
- wherein said controlling means sets said second gain G2 prior to said first gain G1 over a time period equal to a difference between a time period for which the gain of said level adjustment means reaches a stationary value in accordance with a change in said second gain G2 and a time period for which the gain of said level variant means reaches a stationary value in accordance with a change in said first gain G1.
3 more elements
A power control circuit comprising:
- measuring means for measuring level Li of a specific input signal to meet a requirement for a circuit making a desired response to make the desired response, among a plurality N of input signals fed in parallel, when fed with a signal at a predetermined level Ls,
- combining means for combining said plurality N of input signals to generate a single input signal;
- level variant means for amplifying said single input signal which is generated by said combining means and is to be fed to said circuit, at a stage prior or subsequent to said combining means with a first gain G1;
- level adjustment means for amplifying an output signal obtained as a response of said circuit with a second gain G2;
- and
- controlling means for setting said first gain G1 to a ratio between said predetermined level Ls and the level Li measured by said measuring means and setting said second gain G2 to a ratio between a level Lt of an output signal to be obtained at an output terminal of said level adjustment means and a product of said predetermined level Ls and a gain g of said circuit in a condition for making said desired response,
- wherein said controlling means sets said second gain G2 prior to said first gain G1 over a time period equal to a difference between a time period for which the gain of said level adjustment means reaches a stationary value in accordance with a change in said second gain G2 and a time period for which the gain of said level variant means reaches a stationary value in accordance with a change in said first gain G1.
4 more elements
A power control circuit comprising:
- measuring means for measuring a level Li of an input signal;
- level variant means for amplifying said input signal with a first gain G1 and feeding the amplified input signal to a circuit for making a desired response when fed with a signal at a predetermined level Ls;
- level adjustment means for amplifying an output signal obtained as a response of said circuit with a second gain G2;
- controlling means for setting said first gain G1 to a ratio between said predetermined level Ls and the level Li measured by said measuring means and setting said second gain G2 to a ratio between a level Lt of an output signal to be obtained at an output terminal of said level adjustment means and a product of said predetermined level Ls and a gain g of said circuit in a condition for making said desired response;
- and
- output level watching means for measuring a level of the output signal obtained at the output terminal of said level adjustment means,
- wherein said controlling means sets said second gain G2 prior to said first gain G1 over a time period equal to a difference between a time period for which the gain of said level adjustment means reaches a stationary value in accordance with a change in said second gain G2 and a time period for which the gain of said level variant means reaches a stationary value in accordance with a change in said first gain G1, and
- wherein said controlling means is given in advance a desired value of the level of the output signal to be obtained at the output terminal of said level adjustment means and varies said second gain G2 to a value at which a deviation of the level measured by said output level watching means from said desired value is suppressed.
5 more elements
A power control circuit comprising:
- measuring means for measuring a level Li of a specific input signal to meet a requirement for a circuit making a desired response to make the desired response, among a plurality N of input signals fed in parallel, when fed with a signal at a predetermined level Ls;
- combining means for combining said plurality N of input signals to generate a single input signal;
- level variant means for amplifying said single input signal which is generated by said combining means and is to be fed to said circuit, at a stage prior or subsequent to said combining means with a first gain G1;
- level adjustment means for amplifying an output signal obtained as a response of said circuit with a second gain G2;
- controlling means for setting said first gain G1 to a ratio between said predetermined level Ls and the level Li measured by said measuring means and setting said second gain G2 to a ratio between a level Lt of an output signal to be obtained at an output terminal of said level adjustment means and a product of said predetermined level Ls and a gain g of said circuit in a condition for making said desired response;
- and
- output level watching means for measuring a level of the output signal obtained
- at the output terminal of said level adjustment means,
- wherein said controlling means sets said second gain G2 prior to said first gain G1 over a time period equal to a difference between a time period for which the gain of said level adjustment means reaches a stationary value in accordance with a change in said second gain G2 and a time period for which the gain of said level variant means reaches a stationary value in accordance with a change in said first gain G1, and
- wherein said controlling means is given in advance a desired value of the level of the output signal to be obtained at the output terminal of said level adjustment means and varies said second gain G2 to a value at which a deviation of the level measured by said output level watching means from said desired value is suppressed.
7 more elements
A power control circuit comprising:
- measuring means for measuring a level Li of an input signal;
- level variant means for amplifying said input signal with a first gain G1 and feeding the amplified input signal to a circuit for making a desired response when fed with a signal at a predetermined level Ls;
- level adjustment means for amplifying an output signal obtained as a response of said circuit with a second gain G2;
- and
- controlling means for setting said first gain G1 to a ratio between said predetermined level Ls and the level Li measured by said measuring means and setting said second gain G2 to a ratio between a level Lt of an output signal to be obtained at an output terminal of said level adjustment means and a product of said predetermined level Ls and a gain g of said circuit in a condition for making said desired response, wherein
- said controlling means feeds said level adjustment means with an analog control signal indicating said second gain G2 with an instantaneous value of voltage or current, and
- said level adjustment means includes
- holding means for holding the instantaneous values of a plurality of analog control signals fed by said controlling means, cyclically in an order of time series, and
- selecting means for applying a newest instantaneous value under control of said controlling means, among the instantaneous values of the plurality of analog control signals held by said holding means.
6 more elements
A transmitter comprising;
- measuring means for measuring a level Li of an input signal;
- level variant means for amplifying said input signal with a first gain G1;
- a modulator for generating a modulated wave by modulating a carrier signal in accordance with the input signal fed through said level variant means, said modulator having a desired characteristic when fed with a signal at a predetermined level Ls;
- level adjustment means for generating a transmission wave to be sent to a transmission channel by amplifying the modulated wave generated by said modulator with a second gain G2;
- and
- controlling means for setting said first gain G1 to a ratio between said predetermined level Ls and the level Li measured by said measuring means and setting said second gain G2 to a ratio between a level Lt of the transmission wave to be obtained at an output terminal of said level adjustment means and a product of said predetermined level Ls and a gain g of said modulator in a condition for making a desired response,
- wherein said controlling means sets said second gain G2 prior to said first gain G1 over a time period equal to a difference between a time period for which the gain of said level adjustment means reaches a stationary value in accordance with a change in said second gain G2 and a time period for which the gain of said level variant means reaches a stationary value in accordance with a change in said first gain G1.
4 more elements
A transmitter comprising:
- combining means for combining a plurality of input signals fed in parallel and generating a single input signal;
- a modulator for generating a modulated wave by modulating a carrier signal in accordance with the single input signal, said modulator having a desired characteristic when a level of said single input signal is at a predetermined level Ls;
- level variant means for amplifying with a first gain G1 said single input signal to be fed to said modulator through said combining means, at a stage prior or subsequent to the combining means;
- measuring means for measuring levels of said plurality of input signals;
- level adjustment means for generating a transmission wave to be sent out to a transmission channel by amplifying the modulated wave generated by said modulator with a second gain G2;
- and
- controlling means for reducing the first gain G1 of said level valiant means and enlarging the second gain G2 of said level adjustment means, when the level of at least one input signal exceeds a threshold value in said measuring means,
- wherein said controlling means sets said second gain G2 prior to said first gain G1 over a time period equal to a difference between a time period for which the gain of said level adjustment means reaches a stationary value in accordance with a change in said second gain G2 and a time period for which the gain of said level variant means reaches a stationary value in accordance with a change in said first gain G1.
5 more elements
A transmitter comprising:
- measuring means for measuring a level Li of an input signal;
- level variant means for amplifying said input signal with a first gain input G1;
- a modulator for generating a modulated wave by modulating a carrier signal in accordance with the input signal fed through said level variant means, said modulator having a desired characteristic when fed with a signal at a predetermined level Ls;
- level adjustment means for generating a transmission wave to be sent to a transmission channel by amplifying the modulated wave generated by said modulator with a second gain G2;
- controlling means for setting said first gain G1 to a ratio between said predetermined level Ls and the level Li measured by said measuring means and setting said second gain G2 to a ratio between a level Lt of the transmission wave to be obtained an output terminal of said level adjustment means and a product of said predetermined level Ls and a gain g of said modulator in a condition for making a desired response;
- and
- output level watching means for measuring a level of the transmission wave outputted by said level adjustment means,
- wherein said controlling means sets said second gain G2 prior to said first gain G1 over a time period equal to a difference between a time period for which the gain of said level adjustment means reaches a stationary value in accordance with a change in said second gain G2 and a time period for which the gain of said level variant means reaches a stationary value in accordance with a change in said first gain G1, and
- wherein said controlling means is given in advance a desired value of the level of the transmission wave to be outputted by said level adjustment means and varies said second gain G2 to a value at which a deviation of the level measured by said output level watching means from said desired value is suppressed.
6 more elements
A transmitter comprising:
- combining means for combining a plurality of input signals fed in parallel and generating a single input signal;
- a modulator for generating a modulated wave by modulating a carrier signal in accordance with the single input signal, said modulator having a desired characteristic when a level of said single input signal is at a predetermined level Ls;
- level variant means for amplifying with a first gain G1 said single input signal to be fed to said modulator through said combining means, at a stage prior or subsequent to the combining means;
- measuring means for measuring levels of said plurality of input signals;
- level adjustment means for generating a transmission wave to be sent out to a transmission channel by amplifying the modulated wave generated by said modulator with a second gain G2;
- controlling means for reducing the first gain G1 of said level variant means and enlarging the second gain G2 of said level adjustment means, when the level of at least one input signal exceeds a threshold value in said measuring means;
- and
- output level watching means for measuring a level of the transmission wave outputted by said level adjustment means,
- wherein said controlling means sets said second gain G2 prior to said first gain G1 over a time period equal to a difference between a time period for which the gain of said level adjustment means reaches a stationary value in accordance with a change in said second gain G2 and a time period for which the gain of said level variant means reaches a stationary value in accordance with a change in said first gain G1, and
- wherein said controlling means is given in advance a desired value of the level of the transmission wave to be outputted by said level adjustment means and varies said second gain G2 to a value at which a deviation of the level measured by said output level watching means from said desired value is suppressed.
7 more elements
A transmitter comprising;
- measuring means for measuring a level Li of an input signal;
- level variant means for amplifying said input signal with a first gain G1;
- a modulator for generating a modulated wave by modulating a carrier signal in accordance with the input signal fed through said level variant means, said modulator having a desired characteristic when fed with a signal at a predetermined level Ls;
- level adjustment means for generating a transmission wave to be sent to a transmission channel by amplifying the modulated wave generated by said modulator with a second gain G2;
- and
- controlling means for setting said first gain G1 to a ratio between said predetermined level Ls and the level Li measured by said measuring means and setting said second gain G2 to a ratio between a level Lt of a transmission wave to be obtained at an output terminal of said level adjustment means and a product of said predetermined level Ls and a gain g of said modulator in a condition for making a desired response,
- wherein said controlling means feeds said level adjustment means with an analog control signal indicating said second gain G2 with an instantaneous value of voltage or current, and
- wherein said level adjustment means includes
- holding means for holding the instantaneous values of a plurality of analog control signals fed by said controlling means, cyclically in an order of time series, and
- selecting means for applying a newest instantaneous value under control of said controlling means, among the values of the plurality of analog control signals held by said holding means.
7 more elements
Dependencies are inferred from the claim text.