CN101989885A - Frequency modulation receiver and receiving method thereof - Google Patents
Frequency modulation receiver and receiving method thereof Download PDFInfo
- Publication number
- CN101989885A CN101989885A CN2009101618180A CN200910161818A CN101989885A CN 101989885 A CN101989885 A CN 101989885A CN 2009101618180 A CN2009101618180 A CN 2009101618180A CN 200910161818 A CN200910161818 A CN 200910161818A CN 101989885 A CN101989885 A CN 101989885A
- Authority
- CN
- China
- Prior art keywords
- signal
- frequency
- frequency modulation
- mean value
- control voltage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Landscapes
- Channel Selection Circuits, Automatic Tuning Circuits (AREA)
- Circuits Of Receivers In General (AREA)
- Superheterodyne Receivers (AREA)
Abstract
The invention provides a frequency modulation receiver and a receiving method thereof. The frequency modulation receiver comprises an automatic frequency controller and a signal judger, wherein the automatic frequency controller receives a frequency modulation-demodulation signal from a radio-frequency signal; and the frequency modulation-demodulation signal outputs a control voltage to control the oscillation frequency of a local oscillator; a signal searching judger is coupled with the automatic frequency controller to receive the control voltage and judge whether the radio-frequency signal is a frequency modulation signal according to the control voltage and a preset range.
Description
Technical field
The present invention relates to frequency modulation(FM) receiver and its method of reseptance, particularly relate to frequency modulation(FM) receiver and method of reseptance thereof with signal determining device.
Background technology
Frequency modulation(FM) (FM, frequency modulation) is a kind of modulation technique of often using on the telecommunications.FM utilizes the frequency change of the carrier wave of the transmission signal that the transmission end sends to represent to desire information conveyed.Usually, desire information conveyed and present, for example contain the electronic signal of audio mail with the form of an electronic signal, and the FM technology to be amplitude of vibration with this electronic signal be reflected on the frequency change that transmits signal carrier with a certain ratio.
The FM broadcast system of often listening in our daily life is the FM The Application of Technology.The frequency range of the normal FM broadcast system that uses is between 88-108MHz at present, wherein comprises 100 channels, and the frequency range of each channel is 100kHz.The user utilizes the FM receiver to select the channel of oneself wanting.For making things convenient for the user, the FM receiver has the function of searching the FM signal usually.The FM receiver can one channel then the radiofrequency signal that in each channel, received of the judgement of a channel whether be the FM signal, this is the FM signal search.Thus, can remove from user oneself in 100 channels channel then a channel search the puzzlement that whether has the FM signal in each channel.
In the prior art, the FM receiver is to utilize the ratio (SNR, signal to noise ratio) of FM signal and noise in the channel to judge whether the radiofrequency signal that is received is the FM signal in this channel.Fig. 1 is the calcspar of existing FM receiver 100.FM receiver 100 receives a radiofrequency signal R.RF amplifier 110 amplifies this radiofrequency signal R, through a frequency mixer 120 radiofrequency signal R is reduced to intermediate frequency.Pass through known demodulation process such as IF amplifier 130, amplitude limiter 140, FM demodulator 150 again after radiofrequency signal R reduced to intermediate frequency, obtain the FM restituted signal.This FM restituted signal is delivered to SNR calculator 180, calculates SNR.Signal determining device 190 judges according to this SNR and a predetermined critical whether this radiofrequency signal is the FM signal again.Utilize SNR to judge that maximum shortcoming is that the SNR value is difficult to obtain.Have many kinds of methods can obtain the SNR value, the most basic notion is with FM signal and noise separation in this channel, calculates SNR respectively after the signal calculated intensity again.This needs quite complicated circuit to carry out these work, by those skilled in the art is known.Just the system complexity and the cost of whole FM receiver have been increased thus.
Therefore, need a more simple FM frequency modulation(FM) receiver and its method of reseptance to reduce system complexity and cost.
Summary of the invention
The invention provides a kind of frequency modulation(FM) receiver, be used for the frequency modulation(FM) system.This frequency modulation(FM) receiver comprises an automatic frequency controller and a signal determining device.This automatic frequency controller, receiving demodulation are controlled voltage to control the concussion frequency of a local oscillator from a frequency modulation(FM) restituted signal of a radiofrequency signal according to this frequency modulation(FM) restituted signal output one.This signal search determining device is coupled to this automatic frequency controller, receives this control voltage, judges according to this a control voltage and a preset range whether this radiofrequency signal is a frequency modulated signal.
The invention provides a kind of frequency modulated signal method of reseptance, be used for the frequency modulation(FM) system.This frequency modulated signal method of reseptance comprises the following step: receiving demodulation is controlled voltage to control the concussion frequency of a local oscillator from a frequency modulation(FM) restituted signal of a radiofrequency signal according to this frequency modulation(FM) restituted signal output one; And judge according to this a control voltage and a preset range whether this radiofrequency signal is a frequency modulated signal.
The invention provides a kind of frequency modulation(FM) receiver.But the frequency modulation(FM) receiver that is somebody's turn to do search signal comprises an antenna, a radio frequency amplifier, a frequency mixer, a frequency modulation demodulator, an automatic frequency controller, a signal determining device and a local oscillator.This antenna receives a radiofrequency signal.This radio frequency amplifier amplifies this radiofrequency signal.This frequency mixer receives a radiofrequency signal and the local oscillator signal after this amplification, and the radiofrequency signal after will amplifying with this this locality oscillator signal is reduced to intermediate frequency, exports an intermediate-freuqncy signal.This frequency modulation demodulator is coupled to this frequency mixer, receives this intermediate-freuqncy signal, and this intermediate-freuqncy signal is carried out demodulation and exported a frequency modulation(FM) restituted signal.This automatic frequency controller is coupled to this frequency modulation demodulator, receives this frequency modulation(FM) restituted signal, controls voltage to control the concussion frequency of a local oscillator according to this frequency modulation(FM) restituted signal output one.This signal determining device is coupled to this automatic frequency controller, receives this control voltage, judges according to this a control voltage and a preset range whether this radiofrequency signal is a frequency modulated signal.This local oscillator is exported this this locality oscillator signal according to this control voltage.
The invention provides a kind of frequency modulated signal method of reseptance, be used for the frequency modulation(FM) receiver, comprise the following step: receive a radiofrequency signal; Amplify this radiofrequency signal; Radiofrequency signal after will amplifying with a local oscillator signal is reduced to intermediate frequency, exports an intermediate-freuqncy signal; This intermediate-freuqncy signal is carried out demodulation and exported a frequency modulation(FM) restituted signal; According to this frequency modulation(FM) restituted signal, output one control voltage is to control the concussion frequency of a local oscillator; According to this a control voltage and a preset range, judge whether this radiofrequency signal is a frequency modulated signal.
Description of drawings
Fig. 1 is the calcspar of existing FM receiver 100.
But Fig. 2 is a frequency modulation(FM) (FM) receiver 200 according to the search signal of one embodiment of the invention.
Fig. 3 is the frequency modulated signal method of reseptance 300 according to one embodiment of the invention.
Fig. 4 is the calcspar according to the signal determining device 280 of one embodiment of the invention.
Fig. 5 is the circuit diagram according to the comparator 420 of one embodiment of the invention.
The reference numeral explanation
100～existing FM receiver; 110～RF amplifier;
120～frequency mixer; 130～intermediate frequency amplifier;
140～amplitude limiter; 150～FM demodulator;
160～automatic frequency controller (AFC, automatic frequency controller);
170～local oscillator; 180～SNR calculator;
190～signal determining device;
A but frequency modulation(FM) (FM) receiver of 200～search signal;
210～RF amplifier; 220～frequency mixer;
230～intermediate frequency amplifier; 240～amplitude limiter;
250～FM demodulator;
260～automatic frequency controller (AFC, automatic frequency controller);
270～local oscillator; 280～signal determining device;
300～be used for the signal search method of frequency modulation(FM) receiver;
310-360～the be used for signal search step of frequency modulation(FM) receiver;
410～average circuit; 420～direct voltage is device relatively;
510-520～operational amplification circuit; 530～AND assembly.
Embodiment
For above and other objects of the present invention, feature and advantage can be become apparent, cited below particularlyly go out preferred embodiment, and be described with reference to the accompanying drawings as follows.
Embodiment:
Fig. 2 is a frequency modulation(FM) (FM) receiver 200 according to the signal judged of one embodiment of the invention.This FM receiver 200 has a radio frequency amplifier 210, a frequency mixer 220, an intermediate frequency amplifier 230, an amplitude limiter 240, a FM demodulator 250, an automatic frequency controller (AFC, automatic frequency controller) 260, one local oscillator 270 and a signal determining device 280.
Fig. 3 is the frequency modulated signal method of reseptance 300 according to one embodiment of the invention.This FM receiver 200 that can judge signal receives a radiofrequency signal R, as step 310.Radio frequency amplifier 210 amplifies this radiofrequency signal R, as step 320.Then utilize the radiofrequency signal after frequency mixer 220 will amplify with a local oscillator signal to reduce to intermediate frequency, as step 330.The signal that 230 pairs of intermediate frequency amplifiers are reduced to intermediate frequency amplifies, and exports an intermediate-freuqncy signal.240 pairs of these intermediate-freuqncy signals of amplitude limiter are carried out amplitude limit to reduce noise.Intermediate-freuqncy signal behind 250 pairs of amplitude limits of FM demodulator is carried out the FM demodulation, and exports a FM restituted signal, as step 340.
This FM restituted signal then is sent to AFC 260, and this AFC 260 is according to this FM restituted signal, and output one control voltage is to control the concussion frequency of this local oscillator 270, as step 350.The mechanism of a back coupling has been set up in frequency mixer 220, intermediate frequency amplifier 230, amplitude limiter 240, FM demodulator 250, AFC 260, local oscillator 270 formed loops.This back coupling mechanism makes that the frequency reducing error is able to be adjusted by the FM restituted signal, and then makes frequency mixer 220 be utilized the local oscillator signal of this local oscillator accurately radio frequency FM signal to be reduced to predetermined intermediate frequency.Whether we can be found to control voltage that AFC260 exports and this radiofrequency signal has to a certain degree related for the FM signal.If the non-FM signal of this radiofrequency signal, this moment, this back coupling mechanism can not be reduced to radiofrequency signal predetermined intermediate frequency.Very big difference will be arranged when thus, AFC 260 will be the FM signal with this radiofrequency signal according to the control voltage of this FM restituted signal output.Even when this radiofrequency signal be the FM signal, but signal is too constantly faint, backs coupling mechanism is possibly the frequency reducing error can't be adjusted in the permissible scope for this.It is also different when thus, AFC 260 will be the FM signal with this radiofrequency signal according to the control voltage of this FM restituted signal output.Therefore, we can inference, and when this radiofrequency signal was effective FM signal, the control voltage that AFC 260 is exported should be within a preset range.Otherwise, when this control voltage outside a preset range, the non-effective FM signal of this radiofrequency signal of decidable then.In view of the above, signal determining device 280 judges according to this a control voltage and a preset range whether this radiofrequency signal is the FM signal, as step 360.And this preset range can be decided according to actual communication condition, and those skilled in the art need not can design this preset range under the undo experimentation.
Fig. 4 is the calcspar according to the signal determining device 280 of one embodiment of the invention.This signal determining device 280 comprises an average circuit 410 and a direct current voltage comparator 420.This average circuit 410 is coupled to AFC 260, receives this control voltage, exports a mean value of this control voltage.This average circuit 410 can be an integrator, in a scheduled period this control voltage is made integration, and periodically exports this integrated value.This average circuit 410 also can capture the maximum and the minimum value of this control voltage in the scheduled period, maximum and minimum value is averaged again, and periodically exports this mean value.This average circuit 410 can carry out the observation of a scheduled period to control voltage, can avoid signal determining device 280 to cause erroneous judgement thus, or cause erroneous judgement because of suddenly excessive noise or signal attenuation because of this back coupling mechanism unsettled control magnitude of voltage before reaching stable state.Those skilled in the art can design the circuit of various different aspects according to the purpose that average circuit 410 exists.Voltage comparator 420 is coupled to this average circuit 410, in this mean value drops on this preset range, judges that then this radiofrequency signal is the FM signal, outside this mean value drops on this preset range, then judges the non-FM signal of this radiofrequency signal.
Fig. 5 is the circuit diagram according to the comparator 420 of one embodiment of the invention.This comparator 420 comprises first operational amplification circuit 510, second operational amplification circuit 520, AND assembly 530.The negative terminal of first operational amplification circuit 510 is coupled to this average circuit 410, and anode couples one first reference voltage.First operational amplification circuit 510 is exported one first comparative result according to this mean value and this first reference voltage.When first reference voltage during, first operational amplification circuit, 510 outputs, one high voltage greater than this mean value, representative in logic 1.When first reference voltage during, first operational amplification circuit, 510 outputs, one low-voltage less than this mean value, representative in logic 0.Similarly, the anode of second operational amplification circuit 520 is coupled to this average circuit 410, and negative terminal couples one second reference voltage.Second operational amplification circuit 520 is exported one second comparative result according to this mean value and this second reference voltage.When second reference voltage during, second operational amplification circuit, 520 outputs, one high voltage less than this mean value, representative in logic 1.When first reference voltage during, first operational amplification circuit, 520 outputs, one low-voltage greater than this mean value, representative in logic 0.We suppose that when this radiofrequency signal is the FM signal mean value of average circuit 410 outputs can drop between first reference voltage and second reference voltage, for example first reference voltage＞mean value＞second reference voltage.Thus when mean value＞first reference voltage or mean value＜second reference voltage, first operational amplification circuit 510 or second operational amplification circuit, 520 one of them circuit can output LOW voltages, promptly in logic 0.AND assembly 530 is coupled to this first and second computing circuit 510,520, judges signal according to this first and second comparative result output one, represents whether this radiofrequency signal is the FM signal.Only under the situation of first reference voltage＞mean value＞second reference voltage, first and second operational amplification circuit 510,520 just can equal output HIGH voltage, promptly in logic 1.So representing this radiofrequency signal when AND assembly 530 exports 1 is the FM signal, representing this radiofrequency signal non-when AND assembly 530 exports 0 is the FM signal.Those skilled in the art can do suitable variation to comparator 420.
The present invention avoids using SNR as the foundation of this radiofrequency signal of judgement as the FM signal, and utilizes AFC control voltage as basis for estimation, thereby can save the SNR calculator, and the AFC circuit just is the circuit of necessary existence in the FM receiver originally.Therefore, the present invention can reduce the system complexity and the cost of FM receiver, and realizes judging whether this radiofrequency signal is the purpose of FM signal.
Though the present invention discloses as above with preferred embodiment; so it is not in order to limit scope of the present invention; those skilled in the art can do some changes and retouching under the premise without departing from the spirit and scope of the present invention, so protection scope of the present invention is as the criterion with claim of the present invention.
Claims (18)
1. frequency modulation(FM) receiver comprises:
One automatic frequency controller, receiving demodulation are controlled voltage to control the concussion frequency of a local oscillator from a frequency modulation(FM) restituted signal of a radiofrequency signal according to this frequency modulation(FM) restituted signal output one; And
One signal determining device is coupled to this automatic frequency controller, receives this control voltage, judges according to this a control voltage and a preset range whether this radiofrequency signal is a frequency modulated signal.
2. frequency modulation(FM) receiver as claimed in claim 1, wherein this signal determining device also comprises:
One average circuit is coupled to this automatic frequency controller, receives this control voltage, exports a mean value of this control voltage.
3. frequency modulation(FM) receiver as claimed in claim 2, wherein this mean value is derive from interior this control voltage max of a very first time and minimum value average.
4. frequency modulation(FM) receiver as claimed in claim 2, wherein this signal determining device also comprises:
One voltage comparator is coupled to this average circuit, in this mean value drops on this preset range, judges that then this radiofrequency signal is this frequency modulated signal, outside this mean value drops on this preset range, then judges non-this frequency modulated signal of this radiofrequency signal.
5. frequency modulation(FM) receiver as claimed in claim 4, wherein this voltage comparator also comprises:
One first operational amplification circuit is coupled to this average circuit, exports one first comparative result according to this mean value and one first reference voltage;
One second operational amplification circuit is coupled to this average circuit, exports one second comparative result according to this mean value and one second reference voltage; And
One AND assembly is coupled to this first and second operational amplification circuit, judges signal according to this first and second comparative result output one, represents whether this radiofrequency signal is this frequency modulated signal.
6. frequency modulated signal method of reseptance comprises:
Receiving demodulation is controlled voltage to control the concussion frequency of a local oscillator from a frequency modulation(FM) restituted signal of a radiofrequency signal according to this frequency modulation(FM) restituted signal output one; And
Judge according to this a control voltage and a preset range whether this radiofrequency signal is a frequency modulated signal.
7. frequency modulated signal method of reseptance as claimed in claim 6, wherein this determination methods also comprises the mean value according to this control voltage, judges whether this radiofrequency signal is this frequency modulated signal.
8. frequency modulated signal method of reseptance as claimed in claim 7, wherein this mean value is derive from interior this control voltage max of a very first time and minimum value average.
9. frequency modulated signal method of reseptance as claimed in claim 7, this determination methods also comprises:
In this mean value drops on this preset range, judge that then this radiofrequency signal is this frequency modulated signal, and
Outside this mean value drops on this preset range, then judge non-this frequency modulated signal of this radiofrequency signal.
10. frequency modulation(FM) receiver comprises:
One antenna receives a radiofrequency signal;
One radio frequency amplifier amplifies this radiofrequency signal;
One frequency mixer receives a radiofrequency signal and a local oscillator signal after this amplification, and the rf frequency modulation signal after will amplifying with this this locality oscillator signal is reduced to intermediate frequency, exports an intermediate-freuqncy signal;
One frequency modulation demodulator is coupled to this frequency mixer, receives this intermediate-freuqncy signal, and this intermediate-freuqncy signal is carried out demodulation and exported a frequency modulation(FM) restituted signal;
One automatic frequency controller is coupled to this frequency modulation demodulator, receives this frequency modulation(FM) restituted signal, controls voltage to control the concussion frequency of a local oscillator according to this frequency modulation(FM) restituted signal output one;
One signal determining device is coupled to this automatic frequency controller, receives this control voltage, judges according to this a control voltage and a preset range whether this radiofrequency signal is a frequency modulated signal; And
One local oscillator is exported this this locality oscillator signal according to this control voltage.
11. frequency modulation(FM) receiver as claimed in claim 10, wherein this signal determining device also comprises:
One average circuit is coupled to this automatic frequency controller, receives this control voltage, exports a mean value of this control voltage.
12. frequency modulation(FM) receiver as claimed in claim 11, wherein this average signal is derive from interior this control voltage max of a very first time and minimum value average.
13. frequency modulation(FM) receiver as claimed in claim 11, wherein this channel determining device also comprises:
One voltage comparator is coupled to this average circuit, in this mean value drops on this preset range, judges that then this radiofrequency signal is this frequency modulated signal, outside this mean value drops on this preset range, then judges non-this frequency modulated signal of this radiofrequency signal.
14. frequency modulation(FM) receiver as claimed in claim 13, wherein this voltage comparator also comprises:
One first operational amplification circuit is coupled to this average circuit, exports one first comparative result according to this mean value and one first reference voltage;
One second operational amplification circuit is coupled to this average circuit, exports one second comparative result according to this mean value and one second reference voltage; And
One AND assembly is coupled to this first and second computing circuit, judges signal according to this first and second comparative result output one, represents whether this radiofrequency signal is this frequency modulated signal.
15. a frequency modulated signal method of reseptance comprises:
Receive a radiofrequency signal;
Amplify this radiofrequency signal;
Radiofrequency signal after will amplifying with a local oscillator signal is reduced to intermediate frequency, exports an intermediate-freuqncy signal;
This intermediate-freuqncy signal is carried out demodulation and exported a frequency modulation(FM) restituted signal;
According to this frequency modulation(FM) restituted signal, output one control voltage is to control the concussion frequency of a local oscillator;
According to this a control voltage and a preset range, judge whether this radiofrequency signal is a frequency modulated signal.
16. frequency modulated signal method of reseptance as claimed in claim 15, wherein this determination methods also comprises the mean value according to this control voltage, judges whether this radiofrequency signal is this frequency modulated signal.
17. frequency modulated signal method of reseptance as claimed in claim 16, wherein this mean value is derive from interior this control voltage max of a very first time and minimum value average.
18. frequency modulated signal method of reseptance as claimed in claim 16, this determination methods also comprises:
In this mean value drops on this preset range, judge that then this radiofrequency signal is this frequency modulated signal, and
Outside this mean value drops on this preset range, then judge non-this frequency modulated signal of this radiofrequency signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009101618180A CN101989885A (en) | 2009-08-03 | 2009-08-03 | Frequency modulation receiver and receiving method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009101618180A CN101989885A (en) | 2009-08-03 | 2009-08-03 | Frequency modulation receiver and receiving method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN101989885A true CN101989885A (en) | 2011-03-23 |
Family
ID=43746256
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2009101618180A Pending CN101989885A (en) | 2009-08-03 | 2009-08-03 | Frequency modulation receiver and receiving method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101989885A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105229928A (en) * | 2013-05-22 | 2016-01-06 | 德克萨斯仪器股份有限公司 | The method estimated for signal quality and control and circuit |
| CN111490839A (en) * | 2020-04-20 | 2020-08-04 | 吉林省广播电视研究所(吉林省广播电视局科技信息中心) | Frequency modulation broadcasting frequency measurement demodulation electronic system |
| US11362870B2 (en) * | 2020-07-03 | 2022-06-14 | Richwave Technology Corp. | Frequency modulation demodulation device and control method of frequency modulation demodulation device |
-
2009
- 2009-08-03 CN CN2009101618180A patent/CN101989885A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105229928A (en) * | 2013-05-22 | 2016-01-06 | 德克萨斯仪器股份有限公司 | The method estimated for signal quality and control and circuit |
| CN105229928B (en) * | 2013-05-22 | 2017-11-24 | 德克萨斯仪器股份有限公司 | The method and circuit estimated for signal quality and controlled |
| CN111490839A (en) * | 2020-04-20 | 2020-08-04 | 吉林省广播电视研究所(吉林省广播电视局科技信息中心) | Frequency modulation broadcasting frequency measurement demodulation electronic system |
| CN111490839B (en) * | 2020-04-20 | 2021-11-30 | 吉林省广播电视研究所(吉林省广播电视局科技信息中心) | Frequency modulation broadcasting frequency measurement demodulation electronic system |
| US11362870B2 (en) * | 2020-07-03 | 2022-06-14 | Richwave Technology Corp. | Frequency modulation demodulation device and control method of frequency modulation demodulation device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR101665923B1 (en) | Power amplifier saturation detection | |
| KR102332682B1 (en) | Frequency selective logarithmic amplifier with intrinsic frequency demodulation capability | |
| US7072632B2 (en) | Fast signal detection process | |
| AU727017B2 (en) | Variable-gain control | |
| US6253067B1 (en) | Transmitter/receiver having an antenna failure detection system | |
| US8615213B2 (en) | Reducing power consumption of a filter | |
| US8121572B2 (en) | Signal strength detecting device and related method | |
| CN103503312A (en) | Receiver of radiofrequency signals | |
| JPH11187463A (en) | Mobile radio receiver | |
| JPH09162773A (en) | Radio transmitter-receiver with consumed current reduction function | |
| US20230032217A1 (en) | Preamble Signal for Wakeup Communication in a Wireless Communication System | |
| CN101989885A (en) | Frequency modulation receiver and receiving method thereof | |
| US10187122B2 (en) | Near field communications device | |
| US6928273B2 (en) | Radio transmission apparatus for communication using microwave signal | |
| CN214675207U (en) | Device for recognizing pulse amplitude modulation signal based on level control | |
| US4484358A (en) | Receiver having switched capacitor filter | |
| JPH11298348A (en) | Receiver | |
| US8588718B2 (en) | Frequency modulated broadcasts | |
| JP3643364B2 (en) | Receiver | |
| KR100651493B1 (en) | Apparatus and method for controllin gain in receiver | |
| US6141538A (en) | Transmit detection circuit | |
| CN108880587B (en) | Receiver for receiving radio frequency signal, processing method and wireless communication equipment | |
| EP1003284A2 (en) | AGC circuit | |
| GB2393052A (en) | Control of the bias in an amplifier or mixer of a receiver for improved dynamic range, noise performance and efficiency | |
| US20240146357A1 (en) | Dynamic bba gain for near-field radio frequency signal processing |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C12 | Rejection of a patent application after its publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20110323 |