Patent US5278997A successfully refreshed from Google Patents.
US5278997A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dynamically biased amplifier
Assignee: Motorola Solutions Inc
•
Filing: 1993-03-16
•
Granted: 1994-01-11
•
Expires: 2013-03-16
Abstract
Abstract An amplifier (102) which can be dynamically biased is disclosed. A controller (118) determines when to change the bias to the amplifier (102), in order to achieve low frequency splatter. This is accomplished by changing the bias level of amplifier (102) between a substantially linear (class A) mode of operation, and a substantially nonlinear (class B) mode of operation. During the critical periods when the amplifier (102) is being turned into and out of operation, the amplifier (102) is placed in a substantially linear mode of operation, thereby reducing the output harmonics which develop. In another aspect of the invention a radio 300 which employs a dynamically biased amplifier (102) is disclosed.
Inventors
- 👤 William J. Martin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:56
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/02; H04B1/04; H03; H03G; H03G3/00; H03G3/20; H03G3/30; H03G3/3036; H03G3/3042; H03G3/3047; H03F; H03F1/00; H03F1/02; H03F1/0205; H03F1/0261; H03F3/00; H03F3/20; H03F3/24; H03F3/72; H04B1/06; H04B1/16; H04B1/1607; H04B1/1615; H04B2001/0408; H04B2001/045; H04W; H04W88/00
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
136 words
An amplifier, comprising: a preamplifier stage having an output terminal; an amplifier stage for receiving an input signal from the preamplifier's output terminal and providing an output signal; and a control means coupled to the amplifier and preamplifier stages for initializing the amplifier stage to a first bias threshold level with a first bias signal before the amplifier stage provides the output signal, the control means further providing a second bias signal to the preamplifier and amplifier stages a predetermined time after providing the first bias signal to the amplifier stage, the amplifier stage provides the output signal in response to the second bias signal, the second bias signal increasing in bias level until it reaches a second bias threshold level which causes the control means to remove the first bias signal from the amplifier stage.
Claim 2
Dependent Claim
136 words
An amplifier, comprising: a preamplifier stage having an output terminal; an amplifier stage for receiving an input signal from the preamplifier's output terminal and providing an output signal; and a control means coupled to the amplifier and preamplifier stages for initializing the amplifier stage to a first bias threshold level with a first bias signal before the amplifier stage provides the output signal, the control means further providing a second bias signal to the preamplifier and amplifier stages a predetermined time after providing the first bias signal to the amplifier stage, the amplifier stage provides the output signal in response to the second bias signal, the second bias signal increasing in bias level until it reaches a second bias threshold level which causes the control means to remove the first bias signal from the amplifier stage.
Claim 3
Dependent Claim
37 words
An amplifier as defined in claim 1, wherein the amplifier stage operates in a substantially linear mode when in the first bias threshold level, and in a substantially non-linear mode when in the second bias threshold level.
Claim 4
Dependent Claim
28 words
An amplifier as defined in claim 1, wherein the control means further comprises: an integrator coupled to the pre-amplifier and amplifier stages for providing the second bias signal.
Claim 5
Dependent Claim
139 words
A radio capable of transmitting information, comprising: a preamplifier stage having an output terminal; an amplifier stage for receiving an input signal from the preamplifier's output terminal and providing an output signal; and a control means coupled to the amplifier and preamplifier stages for initializing the amplifier to a first bias threshold level with a first bias signal before the amplifier stage provides the output signal, the control means further providing a second bias signal to the preamplifier and amplifier stages a predetermined time after providing the first bias signal to the amplifier stage, the amplifier stage provides the output signal in response to the second bias signal, the second bias signal increasing in bias level until it reaches a second bias threshold level which causes the control means to remove the first bias signal from the amplifier stage.
Claim 6
Dependent Claim
139 words
A radio capable of transmitting information, comprising: a preamplifier stage having an output terminal; an amplifier stage for receiving an input signal from the preamplifier's output terminal and providing an output signal; and a control means coupled to the amplifier and preamplifier stages for initializing the amplifier to a first bias threshold level with a first bias signal before the amplifier stage provides the output signal, the control means further providing a second bias signal to the preamplifier and amplifier stages a predetermined time after providing the first bias signal to the amplifier stage, the amplifier stage provides the output signal in response to the second bias signal, the second bias signal increasing in bias level until it reaches a second bias threshold level which causes the control means to remove the first bias signal from the amplifier stage.
Claim 7
Dependent Claim
17 words
A radio as defined in claim 4, wherein the radio is a time division multiplexed (TDM) radio.
Claim 8
Dependent Claim
37 words
A radio as defined in claim 4, wherein the amplifier stage operates in a substantially linear mode when in the first bias threshold level, and in a substantially non-linear mode when in the second bias threshold level.
Claim 9
Independent Claim
103 words
A method for dynamically biasing an amplifier having an amplifier stage and a preamplifier stage, the amplifier providing an output signal, comprising the steps of: biasing the amplifier stage to a first bias threshold level with a first bias signal prior to the amplifier providing the output signal; applying a second bias signal which is increasing in bias level to the amplifier stage and to the preamplifier stage substantially upon the amplifier beginning to provide the output signal; and removing the first bias signal which is being applied to the amplifier stage upon the second bias signal reaching a second bias threshold level.
Claim 10
Independent Claim
103 words
A method for dynamically biasing an amplifier having an amplifier stage and a preamplifier stage, the amplifier providing an output signal, comprising the steps of: biasing the amplifier stage to a first bias threshold level with a first bias signal prior to the amplifier providing the output signal; applying a second bias signal which is increasing in bias level to the amplifier stage and to the preamplifier stage substantially upon the amplifier beginning to provide the output signal; and removing the first bias signal which is being applied to the amplifier stage upon the second bias signal reaching a second bias threshold level.
Claim 11
Dependent Claim
55 words
A method for dynamically biasing an amplifier as defined in claim 7, further comprising the step of: reapplying the first bias signal to the amplifier stage upon no output signal being provided by the amplifier; and gradually reducing the second bias signal over a predetermined period of time upon the first bias signal being reapplied.
References Cited (Backward Citations)
US3740670A
Cited
US4464633A
Cited
US4465670A
Cited
US4549138A
Cited
US4592073A
Cited
US4644293A
Cited
US5087893A
Cited
US5196806A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-01-10 | 1997-07-12 | 1998-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-01-10 | 2001-07-12 | 2002-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-01-10 | 2005-07-12 | 2006-01-11 | $7700.00 | Window Closed / Lapsed |