Amplifier circuit
AssigneeA.B. Dick Holdings Limited
InventorIan J Forster
Life of this patent
Estimating the term…
Abstract
An amplifier circuit for amplifying an input signal to generate an amplifier output signal incorporates a cascaded series of reflection amplifiers arranged along a signal path and operative to amplify signals propagating in a forward direction along the signal path. The circuit is operative to counteract signal propagation in a reverse direction along the signal path, thereby hindering spontaneous oscillation from arising within the circuit. Incorporation of reflection amplifiers into the circuit enables it to provide high gain, for example 50 dB, while consuming low currents, for example, tens of microamperes. The circuit is especially suitable for use at intermediate frequencies in radio receivers such as mobile telephones.
Claims10
An amplifier circuit for receiving an input signal and providing a corresponding amplified output signal, the circuit comprising:
- a) a plurality of reflection amplifiers cascaded in series along a signal path and operative to amplify the input signal propagating in a forward direction therealong to provide the output signal;
- and
- b) connecting means for connecting the reflection amplifiers to form the signal path and for hindering signal propagation in a reverse direction therealong, thereby counteracting spontaneous oscillation from arising within the circuit, the connecting means incorporating filters which are interposed between neighboring reflection amplifiers along the signal path, and modulating means for modulating the input signal to associated sideband signal components and converting to and from the associated sideband signal components along the path, the filters and the modulating means being operative to promote signal propagation in the forward direction along the path and hinder signal propagation in the reverse direction therealong.
An intermediate frequency strip incorporating an amplifier circuit for receiving an input signal and providing a corresponding amplified output signal, the circuit comprising:
- a) a plurality of reflection amplifiers cascaded in series along a signal path and operative to amplify the input signal propagating in a forward direction therealong to provide the output signal;
- and
- b) connecting means for connecting the reflection amplifiers to form the signal path and for hindering signal propagation in a reverse direction therealong, thereby counteracting spontaneous oscillation from arising within the circuit, the connecting means incorporating filters which are interposed between neighboring reflection amplifiers along the signal path, and modulating means for modulating the input signal to associated sideband signal components and converting to and from the associated sideband signal components along the path, the filters and the modulating means being operative to promote signal propagation in the forward direction along the path and hinder signal propagation in the reverse direction therealong.
An intermediate frequency receiver incorporating an amplifier circuit for receiving an input signal and providing a corresponding amplified output signal, the circuit comprising:
- a) a plurality of reflection amplifiers cascaded in series along a signal path and operative to amplify the input signal propagating in a forward direction therealong to provide the output signal;
- and
- b) connecting means for connecting the reflection amplifiers to form the signal path and for hindering signal propagation in a reverse direction therealong, thereby counteracting spontaneous oscillation from arising within the circuit, the connecting means incorporatingfilters which are interposed between neighboring reflection amplifiers along the signal path, and modulating means for modulating the input signal to associated sideband signal components and converting to and from the associated sideband signal components along the path, the filters and the modulating means being operative to promote signal propagation in the forward direction along the path and hinder signal propagation in the reverse direction therealong.
A mobile telephone incorporating an amplifier circuit for receiving an input signal and providing a corresponding amplified output signal, the circuit comprising:
- a) a plurality of reflection amplifiers cascaded in series along a signal path and operative to amplify the input signal propagating in a forward direction therealong to provide the output signal;
- and
- b) connecting means for connecting the reflection amplifiers to form the signal path and for hindering signal propagation in a reverse direction therealong, thereby counteracting spontaneous oscillation from arising within the circuit, the connecting means incorporatingfilters which are interposed between neighboring reflection amplifiers along the signal path, and modulating means for modulating the input signal to associated sideband signal components and converting to and from the associated sideband signal components along the path, the filters and the modulating means being operative to promote signal propagation in the forward direction along the path and hinder signal propagation in the reverse direction therealong.
A method of amplifying an input signal and providing a corresponding amplified output signal, the method comprising the steps of:
- a) providing a plurality of reflection amplifiers cascaded in series along a signal path, and connecting means for connecting the reflection amplifiers to the signal path and operative to promote signal propagation in a forward direction along the path and counteract signal propagation in a reverse direction therealong, the connecting means incorporating filters which are interposed between neighboring reflection amplifiers along the signal path, and modulating means for modulating the input signal to associated sideband signal components and converting to and from associated sideband signal components along the path, the filters and the modulating means being operative to promote signal propagation in the forward direction along the path and hinder signal propagation in the reverse direction therealong;
- b) receiving the input signal at the signal path;
- c) directing the input signal through the connecting means to one of the reflection amplifiers for amplification therein to provide an amplified signal;
- d) directing the amplified signal in the forward direction to another of the reflection amplifiers for further amplification therein;
- e) repeating step (d) until the amplified signal reaches an output of the signal path;
- and
- f) outputting the amplified signal as the output signal from the signal path.
Dependencies are inferred from the claim text.