US 6,167,244 AGranted

Gain control method and receiver

AssigneeMitsubishi Denki Kabushiki Kaisha

InventorNaohito Tomoe

Life of this patent

Estimating the term…

Loading patent…

Abstract

In an AGC system, a high-speed convergence of an AGC is provided at a burst signal head for an aperiodic burst signal inherent in a base station, having irregular transmitting power from a mobile station, and transmitting power is controlled and a receive of an interference wave is detected for a periodic burst signal according to the presence or absence of voice at the mobile station, thereby preventing an erroneous control of the AGC and maintaining communication quality in a radio base station system. In case of the aperiodic burst signal, a receive level is detected at high speed by, in an attenuator and an AGC amplifier serving as a gain control device, setting the AGC amplifier with a slower transient response to a fixed gain, and turning ON/OFF only the attenuator with a rapid transient response. In case of the periodic burst signal, a synchronous word contained in the burst signal is used to prevent the erroneous control and detect interference in the AGC.

Claims21

Dependent claims

A gain control method used for controlling the gain of a receiver including an attenuator for attenuating an input signal depending upon each of a first set value and a second set value, an amplifier for amplifying said input signal depending upon a control signal, and a controller for generating the first set value, the second set value, and the control signal, said gain control method comprising the steps of:

separately attenuating said input signal using said first set value to obtain a first attenuated input signal, and using said second set value to obtain a second attenuated input signal, and determining a control error of each of said first and second attenuated input signals;
deciding whether a receive level of said input signal falls in a first control error range corresponding to the first set value or a second control error range corresponding to the second set value by comparing the control error of the first attenuated input signal with said first control error range, and comparing the control error of the second attenuated input signal with said second control error range;
and
thereafter controlling the gain by attenuating an input signal in the attenuator using the first set value when it is decided in the decision step that the receive level falls in the first control error range and using the second set value when it is decided that the receive level falls in the second control error range, and amplifying an input signal in the amplifier.

1 more element

A gain control method used for controlling the gain of a receiver including an attenuator for attenuating an input signal depending upon each of a first set value and a second set value, an amplifier for amplifying said input signal by at least a low gain or a high gain depending upon a control signal, and a controller for generating the first set value, the second set value, and the control signal, the gain control method comprising the steps of:

with said amplifier set to a low gain, separately attenuating said input signal using said first set value to obtain a first attenuated input signal, and using said second set value to obtain a second attenuated input signal, and determining a control error of each of said first and second attenuated input signals;
deciding whether a receive level of said input signal falls in a first control error range corresponding to the first set value or a second control error range corresponding to the second set value by comparing the control error of the first attenuated input signal with said first control error range, and comparing the control error of the second attenuated input signal with said second control error range;
and
thereafter controlling the gain of said receiver by attenuating an input signal in the attenuator using the first set value when it is decided in the decision step that the receive level of the input signal falls in the first control error range and using the second set value when it is decided that the receive level falls in the second control error range, and setting the amplifier to a high gain when the receive level of the input signal falls in neither the first control error range nor the second control error range.

1 more element

A gain control method used for controlling the gain of a receiver including a first attenuator for attenuating an input signal depending upon each of a first set value and a second set value, a second attenuator for attenuating an input signal depending upon each of a third set value and a fourth set value, a first amplifier for amplifying an output signal from the first attenuator depending upon a first control signal, a second amplifier for amplifying an output signal from the second attenuator depending upon a second control signal with a higher gain than that of the first amplifier, and a controller for generating the first, second, third, and fourth set values, and the first and second control signals, the gain control method comprising the step of:

deciding in which of a first control error range corresponding to the first set value, a second control error range corresponding to the second set value, a third control error range corresponding to the third set value, and a fourth control error range corresponding to the fourth set value a receive level of an input signal falls;
and
controlling the gain of said receiver by attenuating and amplifying an input signal depending upon the set value and the amplifier corresponding to the control error range in which the receive level of the input signal falls.

A receiver comprising:

an attenuator for separately attenuating an input signal using each of a first set value and a second set value, to obtain a first attenuated input signal and a second attenuated input signal;
an amplifier for amplifying said input signal depending upon a control signal;
and
a controller for generating the first set value, the second set value, and the control signal, wherein the controller includes deciding means for deciding whether a receive level of an input signal falls in a first control error range corresponding to the first set value or a second control error range corresponding to the second set value, by obtaining a control error of each of said first and second attenuated input signals and comparing the control errors with said first and second control error range, respectively, and gain control means for controlling the gain by attenuating an input signal in the attenuator using the first set value when it is decided in the deciding means that the receive level falls in the first control error range and using the second set value when it is decided that the receive level falls in the second control error range, and amplifying an input signal in the amplifier.

1 more element

Dependencies are inferred from the claim text.

Facts

Application: 09/043,467Filed 20 Mar 1998
Granted: 26 Dec 2000
Term ends: Not estimatedThe source records don’t support an estimate.

Classification7 codes

H03G 3/3078
In bandpass amplifiers or in frequency-changers used in a heterodyne receiver: circuits generating control signals for digitally modulated signals
H03G 3/3052
In amplifiers having semiconductor devices: in bandpass amplifiers or in frequency-changers used in a heterodyne receiver
H03G 3/3068
In bandpass amplifiers or in frequency-changers used in a heterodyne receiver: circuits generating control signals for both R.F. and I.F. stages
H04L 7/04
Arrangements for synchronising receiver with transmitter: speed or phase control by synchronisation signals