CN1518246A - Infrared receiver - Google Patents
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- CN1518246A CN1518246A CNA2004100001994A CN200410000199A CN1518246A CN 1518246 A CN1518246 A CN 1518246A CN A2004100001994 A CNA2004100001994 A CN A2004100001994A CN 200410000199 A CN200410000199 A CN 200410000199A CN 1518246 A CN1518246 A CN 1518246A
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Abstract
An infrared-ray receiver includes an infrared-ray receiving portion including a photodiode and converting an optical signal to an electric signal, a first amplifier amplifying the converted electric signal, an automatic gain control amplifier receiving an output of the first amplifier and capable of controlling gain, a band pass filter filtering an electric signal of a frequency, a comparator comparing a preset reference DC voltage and an output of the band pass filter, a demodulator demodulating an output of the comparator, an output portion outputting an output signal of the demodulator, a gap time detection portion receiving one of the output of the demodulator and the output of the comparator and detecting a gap time of a signal; and a gain control portion designed to detect the length of a signal detected by the gap time detection portion and control gain of the automatic gain control amplifier according to whether a sustaining time of a gap time included in the detected signal exceeds a preset reference time value.
Description
Technical field
The present invention relates to a kind of infrared receiver, particularly a kind of have according to the characteristic of input signal determine that input signal is the infrared receiver that noise signal or normal signal are removed the noise signal function.
Background technology
Disclose a kind of typical technology as the traditional infrared line receiver in Korean Patent No.322520, this patent is filed an application and is authorized by Korea S AD Tech Co., Ltd..Do following description for this conventional art with reference to Fig. 1.
According to conventional art shown in Figure 1, infrared ray receiving unit 11 comprises the outside infrared ray input signal that receives of a detection and infrared signal is changed into the photodiode of the signal of telecommunication.Because the signal of telecommunication after transforming is faint, this signal is amplified to suitable grade by first amplifier 12.First amplifier 12 is used for the small-signal at each circuit is amplified to the grade that this signal can suitably be controlled, and will be illustrated this after a while.
The single step of releasing large-signal of being amplified by first amplifier 12 is by being used for the automatic gain control amplifier (AGC amp) 13 of ride gain, and wherein the gain of signal is suitably controlled.In a circuit, by the gain controlling that control particular current or voltage are carried out, its detail operations is explanation with reference to the accompanying drawings after a while.
Signal by AGC amp13 is exaggerated and once more finally by limiting amplifier 14.The operation of infrared ray amplifier does not have limiting amplifier 14 can normally carry out yet.The output signal of limiting amplifier 14 is by the band pass filter (BPF) 15 of the carrier wave in the filtering infrared signal.
One passive device that is called coupling capacitor is plugged between said units, is included in the flip-flop in the output signal of each amplifier with filtering.Yet for the convenience of narrating, the brief description of this passive device will be omitted at this.The output of BPF 15 inputs to gain controller 16 and comparator 17.Gain controller 16 is noise signal or normal signal (for example signal that produces from remote controllers) according to the signal from BPF 15 outputs, produces a gain controlling electric current or a gain-controlled voltage, with the gain of control AGC amp 13.
In Fig. 1, the output of photodiode is imported among the BPF 15 that average frequency is approximately tens of or hundreds of KHz by different amplifiers.To be confirmed as be the voltage a little more than the average voltage of BPF 15 output to the level of the Vref signal of one of input signal of device 17 as a comparison.When one was higher than the voltage input BPF 15 of Vref, comparator 17 was the signal of a Transistor-Transistor Logic level with this voltage transitions, and exports this switching signal.This output signal is by demodulator 18 and remove carrier frequency therein, so the part that is known as " envelope " of this signal is left, and the demodulating process of this signal is finished.
One input signal that is input to infrared receiver generally includes undesired external disturbance, for example the light of fluorescent lamp or sunlight except the infrared ray composition.It is noise contribution that this external intervention light is taken as, and does not want because it is not the designer.
Because noise contribution also is transmitted by the circuit in the infrared receiver, a kind of may be exactly because the increase of noise causes the infrared receiver fault.For infrared receiver can stably move, the said external noise must be removed or suitably restriction.
For this purpose, in conventional art as shown in Figure 1, use gain controller 16 and AGC amplifier 13 to remove noise.When the signal that is input to gain controller 16 is noise signal, gain controller 16 operations, so the gain of AGC amplifier 13 reduces.Like this, noise just has been limited by the transmission of AGC amplifier 13.When input signal is normal signal rather than noise signal, gain controller 16 operations, so the gain of AGC amplifier 13 keeps or increase.Correspondingly, the noise in the output signal of demodulator 18 or schmitt circuit part 19 is suitably removed by above operation, thereby only exports normal signal.
Illustrate with reference to the signal waveform shown in Fig. 2 that detection is separated to be in harmonious proportion by remote controllers and for example input to that the signal of infrared receiver is the noise signal or the method for normal signal.
Fig. 2 represents that infrared receiver is separated and is in harmonious proportion the noise signal 21 of input and the waveform that normal signal 22 is amplified.The amplitude of noise signal 21 reality is littler than the normal signal.Yet, similar for the amplitude that makes things convenient for noise signal 21 of setting forth in Fig. 2 with the amplitude of normal signal 22.Although the noise signal part may be included in the normal signal 22,, this part is no longer illustrated for ease of explaining.
As shown in Figure 2, the waveform of normal signal 22 for example can be distinguished from the waveform of noise signal clearly from the type signal output of remote controllers.Under typical remote control signal situation, the period (being blanking time 25) that a pulse signal input period 23 that the normal signal of carrying on the carrier signal is transfused to and a carrier signal are not imported can clearly be distinguished each other.
Typically, the pulse signal input period 23 was compared with blanking time 25, and the period of blanking time 25 is longer relatively.Correspondingly, the pulse signal input ratio of period 23 in the whole signal period is no more than 50%.Under the situation of noise signal, the period of blanking time 25 does not exist or unlike normal signal but short yet as shown in Figure 2.Conventional patents invention described above is based on infrared signal and has different duty ratios with noise signal.
According to conventional art, for normal remote control signal, gain controller 16 moves like this: in the period of signal input, and the capacitor charging in the gain controller 16; In blanking time, the capacitor discharge.Because when the signal of input infrared receiver when being noise signal, blanking time is short or do not exist, and capacitor continues charging, so the voltage at capacitor two ends surpasses predetermined voltage.
The gain of AGC amplifier 13 by the voltage control between the capacitor two ends.13 operations of AGC amplifier are to reduce gain when capacitor voltage at both ends increases; 13 operations of AGC amplifier are to increase gain when capacitor voltage at both ends reduces.
The increase of the gain of the corresponding to AGC amplifier 13 of direction that increases and reduce with capacitor voltage at both ends and the direction of minimizing can be converted.Therefore, when noise signal was passed through AGC amplifier 13, noise signal will be limited according to above operation.
Under normal remote control signal situation, capacitor is recharge and discharge in the one-period that comprises pulse signal period and blanking time, and the voltage at capacitor two ends is no more than predetermined voltage.Therefore, the normal signal by AGC amplifier 13 can correctly keep its amplitude.
Sum up the operation of gain controller 16, whether gain controller 16 at first determines in capacitor charge or discharge and exports an output signal and control the gain with control amplifier of the charge/discharge of AGC amplifier 13.
The technical characterictic of conventional art is, because an input signal just is confirmed as a normal signal when the ratio of maintenance period modulated and that be input to the pulse signal of infrared receiver is no more than 50% with respect to the whole signal period, otherwise be exactly a noise signal, correspondingly, the gain of AGC is controlled to the limit noise signal.
Yet, in conventional art, to be modulated more strongly because result from the sunlight noise of the external intervention light ratio routine of an electronic fluorescent lamp, it is about 50% that the ratio of pulse signal is lower than, so duty ratio wherein is similar with the duty ratio of normal signal.Therefore, in an infrared receiver circuit, external intervention light is not considered to a kind of noise signal but a kind of normal signal, so the infrared receiver circuit produces misoperation.
Summary of the invention
In order to overcome the above problems, the purpose of this invention is to provide a kind of infrared receiver that can effectively limit or remove the various noise contributions of input, improve its reliability thus.
According to an aspect of the present invention, a kind of infrared receiver comprises: comprise a photodiode and light signal is converted to the infrared ray receiving unit of the signal of telecommunication; Be used to amplify first amplifier of the signal of telecommunication after the conversion; Be used to receive the output of first amplifier and second amplifier of energy ride gain; Be used for filtering and export the band pass filter of the signal of telecommunication of the characteristic frequency that comprises at second amplifier; The comparator that is used for the output of default reference direct voltage of comparison one and band pass filter; The demodulator that is used for the output of demodulation comparator; Be used for the output signal of demodulator is exported the output of the outside of infrared receiver; Be used for one of the output of receiving demodulation device output and comparator also test section blanking time of the blanking time of detection signal; Be used for detecting the length that is spaced apart the detected signal of time detecting part, and whether surpass a predetermined reference time value according to being included in holding time of blanking time in the detection signal, control the gain controlling part of the gain of automatic gain control amplifier.
According to another aspect of the present invention, a kind of infrared receiver with noise remove function comprises: the infrared detection part that is used to detect infrared signal and detected infrared signal is converted into the signal of telecommunication; Be used to amplify first amplifier of the signal of telecommunication after the conversion that results from infrared detection part; Be used to receive the output of first amplifier and second amplifier of energy ride gain; The band pass filter of special component of various compositions that is used for the output signal of filtering second amplifier; Compare the output signal of band pass filter and the comparator of a preset reference voltage; The demodulator that is used for the output signal of demodulation comparator; Be used for the output signal of demodulator is outputed to the output of the outside of infrared receiver; With an automatic gain controller, be used for output signal according to demodulator, the utilization FEEDBACK CONTROL is controlled second Amplifier Gain, and comprises the particular comparator of a Control and Feedback and the circuit of control capacitor operation.
Handle in the process of output signal at infrared receiver according to the present invention, be different from traditional method, consider the characteristic of input signal, just, noise signal is different with normal signal each other, according to noise signal and normal signal can be in infrared receiver the gain of control amplifier.Therefore, can provide a reliable infrared receiver, thereby improve the reliability of the electronic installation that comprises infrared receiver of the present invention.
Description of drawings
Fig. 1 is the block diagram of a traditional infrared line receiver;
Fig. 2 is the view of example of the waveform of a noise signal and a normal signal;
Fig. 3 is the block diagram according to an infrared receiver of one embodiment of the present invention;
Fig. 4 A is an oscillogram of gain controller when importing a normal signal;
Fig. 4 B is an oscillogram of gain controller when importing a noise signal;
Fig. 5 is the block diagram according to an infrared receiver of another preferred embodiment of the present invention;
Fig. 6 is the circuit diagram of an automatic gain controller, a rating unit, a demodulator and an output circuit part according to infrared receiver of the present invention;
Fig. 7 is for explaining a flow chart of operation that has the infrared receiver of noise remove function according to the present invention;
Fig. 8 finishes the view of the preferred embodiment of the normal signal that is input to infrared receiver and a signal for the explanation demodulation;
Fig. 9 is by modulation and the chart that is input to the preferred embodiment of the fluorescent lamp noise signal in the infrared receiver;
Figure 10 is for by weak modulation be input to the chart of the preferred embodiment of the fluorescent lamp noise signal in the infrared receiver;
Figure 11 is the circuit diagram of an AGC interface section;
Figure 12 is the sequential chart of Figure 11;
Figure 13 is the gain of an automatic gain control amplifier and a chart of the relation between control voltage.
Implement best mode of the present invention
With reference to Fig. 3, infrared receiver according to a preferred embodiment of the present invention comprises an infrared ray receiving unit 31, one first amplifier 32, one automatic gain control amplifier, 33, one limiting amplifiers, 34, one band pass filters 35, one gain controller 36, one comparator 37, one demodulators, 38, one outputs 39 and one blanking time detector 40.
Infrared ray receiving unit 31 comprises a photodiode, and converts an input signal to a signal of telecommunication.
First amplifier 32 is used to amplify the signal of telecommunication after the conversion, and is called as preamplifier.
Automatic gain control amplifier 33 receives the output of first amplifier 32, and can pass through gain controller 36 ride gains.
Limiting amplifier 34 amplifies the signal by automatic gain control amplifier 33 once more and finally.
Band pass filter 35 is the signal of telecommunication of the characteristic frequency that comprises in the output of automatic gain control amplifier 33 or limiting amplifier 34 of filtering only.
Gain controller 36 is designed to detector 40 detected detection signals blanking time of one of output that receives comparator 37 and demodulator 38 are carried out length detection, and whether surpass a default reference time value according to the duration of the blanking time in the output signal that is included in output signal in the demodulator 38 or comparator 37, control the gain of automatic gain control amplifier 33.
Comparator 37 compares a default reference direct voltage and band pass filter 15 outputs.
The output of demodulator 38 modulation comparators 37.
Output 39 outputs to the output signal of demodulator 38 outside of infrared receiver.
Blanking time detector 40 receiving demodulation devices 38 and comparator 37 one of output, and blanking time of detection signal.
The waveform of the component units of Fig. 4 A and 4B presentation graphs 3 is below described its operating process.
Fig. 4 A represents that a normal remote control signal is input to infrared receiver.When the time interval of signal is approximately 20ms-25ms, resembling natural daylight, for example under the situation of the white noise of sunlight or an incandescent lamp and so on, exist blanking time hardly.Under the situation of the fluorescent lamp of electronic fluorescent lamp and frequency tripling, because signal has the frequency of a 50Hz or 60Hz, can not surpass about 4ms-5ms the blanking time of modulation signal.
Comparator 37 is passed through in signal output from filter, and by demodulator 38 demodulation.Because needn't be to the demodulation of a signal not necessarily, this signal can not pass through demodulator 38.
In the case, blanking time, detector 40 input needn't be connected to the output of demodulator 38, but was connected to the output of comparator 37.To explain demodulator 38 reason why not necessarily after a while.
Signal after demodulation is imported into detector 40 blanking time, determines promptly input signal has a blanking time how long (i.e. " low " period).If a blanking time is shorter than the default scheduled time, this input signal is confirmed as noise signal.Otherwise input signal is confirmed as normal remote control signal, correspondingly by the method for above description the charge/discharge operation of gain controller 36 is controlled.
As mentioned above, there are the different of length blanking time in noise signal with normal remote control signal, therefore in determining, be set in noise signal and the normal value between blanking time of remote control signal with Preset Time for referencial use, preferably, be the median between the interval betwixt.
For example, be 20ms the blanking time of supposing remote control signal, and noise signal blanking time is 4ms, is set to 12ms with the time for referencial use in decision.When blanking time detector 40 only be designed to when low period of the output of demodulator 38 when when determining, setting the reference value of doing a reference and grow, the capacitor of charge/discharge current part is just carried out charging, then can operate according to the desired normal charge/discharge that carries out like that.
Reference value in circuit is set and can be realized with diverse ways like this.For example, can in providing the method for time constant of charging of a capacitor device and this capacitor of control in the detector 40 blanking time, set reference value.The reference time value of designer's expectation also can be set with the mode of a clock signal sets one specific clock number.The method of more than setting reference value only is the several examples in numerous establishing methods, can carry out various changes and combination to them.
As mentioned above, demodulator 38 not necessarily.Shown in Fig. 4 A and 4B, no matter the output of the signal of comparator 37 still is the signal output of demodulator 38 is imported into detector 40 blanking time, blanking time, detector 40 operation kept same.This is to be defined in millisecond (ms) level because determine the setting reference value of noise signal and normal signal, is considered to same signal in blanking time in the detector 20 so comprise the signal after signal before the demodulation of carrier wave and carrier wave are by the demodulation of filtering.
In addition, blanking time, detector 40 input signal can be from band pass filter 35 outputs, preferably, and from comparator 37 or demodulator 38 outputs.
In other words, even the output signal of comparator 37 is not necessarily by demodulation, because it is shorter to be inserted in the reference value of promptly hanging down period ratio setting the little blanking time of the signal between pulse signal, blanking time, detector 40 charge kept same (the low period is defined as a little blanking time especially, because it may determine obscure mutually the blanking time of a noise signal with described above).
According to the signal that how to continue blanking time of input signal to determine to be input to infrared receiver is noise signal or normal signal, thereby decision is charge/discharge one voltage between the two ends of the capacitor of gain controller 36 normally, still only continues charging.
According to designer's the convenience and the environment of work of the present invention, the degree of the charge or discharge of the voltage between the capacitor two ends of gain controller 36 can suitably change.The numerical value that is used for the capacitor of charge or discharge by change is controlled a charge constant, obtains this variation at an easy rate.
Fig. 5 represents the infrared receiver according to another preferred embodiment of the present invention.This infrared receiver according to another preferred embodiment of the invention comprises an infrared detector 51, one first amplifiers 52, one second amplifiers 53, one band pass filter 54, one comparator 55, one demodulators, 56, one automatic gain controllers 57 and output circuit part R11 and TR11.
Infrared detector 51 detects infrared signal and by photodiode detected conversion of signals is become a signal of telecommunication.
First amplifier 52 amplifies the signal of telecommunication that results from infrared detector 51 generations.
The output signal of being amplified first amplifier 52 again automatically by second amplifier 53 that is called automatic gain control amplifier (AGC amplifier) of automatic gain controller 57 ride gains.In the following description of the present invention, use automatic gain control amplifier to replace second amplifier 53.
54 pairs of output signals from automatic gain control 57 of band pass filter are carried out filtering, and the signal that allows to have a certain frequency bandwidth passes through.Special component in the various compositions of the output signal of band pass filter 54 filtering automatic gain amplifiers 53.
The output signal of 55 pairs of band pass filters 54 of comparator and a preset reference voltage compare.
Output circuit part R11 and TR11 and demodulator 56 are electrically connected and the output signal of demodulator 56 are outputed to the outside of infrared receiver.
The automatic gain controller 57 that constitutes one of unit as core of the present invention is circuit of the gain of a control automatic gain control amplifier 53.When the light signal that is input to infrared receiver is a noise signal.The Vagc voltage of automatic gain controller 57 outputs one on the direction that reduces automatic gain control amplifier 53 gains in infrared receiver is with the limit noise signal.In other cases, the Vagc voltage of automatic gain controller 57 outputs one on increase or maintenance automatic gain control amplifier 53 gain direction.
Followingly describe the present invention with reference to Fig. 6 and respectively constitute the operation of unit and operating characteristic wherein.
At first, Fig. 6 has at length shown automatic gain controller 57, comparator 55, demodulator 56 and output current part R11 and TR11.
The operation of each modular unit in automatic gain controller 57 is described below.
Clock signal generating module 61 receives an output and produces dissimilar internal clock signal clock1-clockN from an oscillator module 60.
Surpass Preset Time the blanking time in being included in demodulator 56 output signals, 25ms for example, blanking time, detector module 62 made output signal GapTimeSig for " height " and export this signal, otherwise making output signal is " low ".
Shown in the waveform of the normal signal among Fig. 8, this normal signal comprises that an information is carried in period blanking time that pulse period on the carrier signal and a carrier wave temporarily are not transfused to.
Be that from the characteristic of the normal signal of remote controllers inputs be the period of about tens microseconds blanking time, and more longer relatively than noise signal.Yet, as shown in Figure 9, an interfering noise signal modulation and being input in the fluorescent lamp noise signal of infrared receiver for example externally, " low " period that is considered to blanking time of this signal is than short.
The amplitude that Fig. 9 is illustrated in noise signal signal in the period is relatively little compared with other periods, and just, can be construed to is that period of blanking time approximately is 4ms.The signal that can determine to be input to infrared receiver by the duration difference of utilizing blanking time is a noise signal or a normal signal.
Figure 10 represents from a signal of fluorescent lamp output.With reference to Figure 10, the period that can be considered to the blanking time of signal does not show it is a feature of fluorescent lamp signal significantly.
As mentioned above, the blanking time of noise signal short relatively than normal signal.Signal detection module 63 distinguishes that the output signal of demodulator 56 is a normal signal or a noise signal.
As shown in Figure 8, in the present invention, " low " period of restituted signal is corresponding to the pulse period of photodiode input signal, and " height " period the keeping the period corresponding to the photodiode input signal of restituted signal.Shorter than a preset length when " low " period of restituted signal, signal detector 63 determines that signals are noise signals and the output signal NOSIG of signal detector 63 is converted to " height ".Longer than preset width when " low " period of restituted signal, the output signal NOSIG of signal detector 63 is output as " low ".In other words, hold time the output signal difference of signal detector 63 according to " low " that in the output signal of signal detector module 63, comprise.
When wherein an input signal is " height " or " low " continuously, NOPULSE detector 64 outputs one output signal NOPULSE is " height ".When a pulse type signal is imported continuously, NOPULSE detector 64 makes the NOPULSE signal be " low ".Just, in NOPULSE detector 64, " high/low " state of output signal is to determine according to the characteristic of input signal.
One charge/discharge controller 65 receives the output of detectors 62 blanking time, signal detector 63 and NOPULSE detector 64, and produces the signal C-ch and the C-dis of the operation that is used to control AGC interface 66 and be used for the sleep signal GapTimeRst of detector 62 blanking time, signal detector 63 and NOPULSE detector 64.
With reference to a circuit diagram of simplifying of AGC interface 66 with at the figure of the time sequential routine shown in Figure 11,12, the operation of charge/discharge controller 65 and AGC interface 66 is described below.
When the signal that is input to infrared receiver is a noise signal because from blanking time detector 62 to produce an output signal GapTimeSig be " low ", the signal C-ch that results from charge/discharge controller 65 is " height ".Switch SW 1 is switched on, so 66 pairs of capacitor C that wherein are provided with of AGC interface are charged.Correspondingly, an output signal Vagc of AGC interface 66 is increased.As signal GapTimeSig when being " height " synchronous signal NOSIG, there are following two kinds of situations for " height ".
First kind of situation is that a noise signal is transfused to, and at this moment, signal NOPULSE is " low ".In this case, signal C_ch becomes " height ", and therefore the electric capacity in AGC interface 66 is recharged.Second kind of situation is the input signal that does not have from the outside.Signal NOPULSE becomes " height " and signal C_dis becomes " height ".Switch SW 2 is opened, and therefore the capacitor C in AGC interface 66 is discharged.
If signal GapTimeSig is that " height " and signal NOSIG are " low ", it means that the signal from the infrared receiver outside is a normal signal.In this case, signal C_ch and C_dis keep " low " state, no matter therefore switch SW 1 or SW2 is closed.Correspondingly, the capacitor C in AGC interface unit 66 is not recharged or discharges, so the gain of automatic gain control amplifier 53 is not changed, and keeps intact.
Concise and to the point operation of concluding AGC interface 66, AGC interface 66 receive the output signal C_ch and the C_dis of charge/discharge controller 65 and produce the gain of control voltage Vagc with control automatic gain control amplifier 53.In the present invention of above narration,, different modification designs can be arranged in the type of automatic gain control amplifier 53 although explanation is the gain minimizing of automatic gain control amplifier 53 when voltage Vagc increases.
The quantity that is used in the amplification end in the infrared receiver of the present invention ought can increase in case of necessity.In addition, the degree of voltage charging between the capacitor C two ends in AGC interface 66 or discharge can suitably be changed according to designer's the convenience or the environment of work of the present invention.This change can be controlled a time constant by the numerical value that change is used in the electric capacity in the charge or discharge and obtain at an easy rate.
Circuit operation of the present invention is described with reference to function and the interactional Fig. 6 about each module, is expressed in flow chart Fig. 7.
Figure 13 represent to gain and the AGC (automatic gain control) voltage Vagc of automatic gain control amplifier 53 between relation.Can find out that automatic gain control amplifier 53 designs like this by increase the Amplifier Gain minimizing as voltage Vagc.
Though the present invention is represented particularly with reference to preferred embodiment wherein and is described, yet, it should be appreciated by those skilled in the art that the different variation that can obtain in the form and details, and do not leave the spirit and scope of the present invention of appended entitlement definition.For example, blanking time, detector can detect blanking time greater or less than 20-25ms.Reference in the detecting operation of signal detector or NOPULSE detector can be changed, or the reference voltage of comparator can be changed.
Claims (10)
1. infrared receiver comprises:
The infrared ray receiving unit comprises a photodiode, and light signal is converted to the signal of telecommunication;
First amplifier is used to amplify the described signal of telecommunication after the conversion;
Second amplifier is used to receive the output of described first amplifier, and the energy ride gain;
Band pass filter is used for the characteristic frequency that comprises is exported in filtering at described second amplifier the signal of telecommunication;
Comparator is used for a reference direct voltage of presetting and the output of described band pass filter are compared;
Demodulator is used for the output of the described comparator of demodulation;
Output is used for the output signal of described demodulator is exported the outside of described infrared receiver;
Blanking time, the test section was used for receiving one that described demodulator is exported and described comparator is exported, and the blanking time of detection signal; With
The gain controlling part, be used for detecting length by the detected signal in described blanking time of test section, and whether surpass a preset reference time value according to being included in holding time of blanking time in the detection signal, control the gain of described automatic gain control amplifier.
2. infrared receiver as claimed in claim 1 is characterized in that, described reference time value is one capacitor device is provided in the test section and controls in the method for time constant of charging of described capacitor and set in blanking time.
3. infrared receiver as claimed in claim 1 is characterized in that, described reference time value is set at littler than the blanking time of the normal signal that is input to infrared receiver.
4. infrared receiver as claimed in claim 1, it is characterized in that, described blanking time, the test section only was designed to liken the reference value of setting for the reference when determining to when long when the scheduled time slot in the output of described demodulator, and a capacitor is carried out discharge.
5. infrared receiver with noise remove function comprises:
The infrared detection part is used to detect infrared signal and detected infrared signal is converted into the signal of telecommunication;
First amplifier is used to amplify the described signal of telecommunication after the conversion that results from described infrared detection part;
Second amplifier is used to receive the output of described first amplifier, and the energy ride gain;
Band pass filter is used for the special component of various compositions of the output signal of described second amplifier of filtering;
Comparator is used for the output signal and a preset reference voltage of described band pass filter are compared;
Demodulator is used for the output signal of the described comparator of demodulation;
Output is used for the output signal of described demodulator is outputed to the outside of described infrared receiver; With
Automatic gain controller is used for the output signal according to described demodulator, and the utilization FEEDBACK CONTROL is controlled described second Amplifier Gain, and comprises the particular comparator of the described feedback of a control and the circuit of the described capacitor operation of a control.
6. infrared receiver as claimed in claim 5 is characterized in that, described FEEDBACK CONTROL uses a switching circuit and to be used for the current source circuit of described capacitor charge/discharge.
7. infrared receiver as claimed in claim 5 is characterized in that, described automatic gain controller comprises:
Detector detected a transmission of exporting from the signal of demodulator and was no less than or the no more than predetermined reference time blanking time;
Signal detector, detect from described blanking time detector signal output be a normal signal or a noise signal;
The NOPULSE detector, according to the characteristic of the input signal of described signal detector, the state of decision output signal;
The charge/discharge controller, receive the output of described blanking time of detector, described input part and described NOPULSE detector, and produce the operation of control automatic gain control (AGC) interface and the signal C-ch and the C-dis that need and be used for the reset signal GapTimeRst of described blanking time of detector, described signal detector and described NOPULSE detector; With
The automatic gain control interface receives the described output signal C_ch and the C_dis of described charge/discharge controller, and produces the control voltage Vagc that can control described second Amplifier Gain.
8. infrared receiver as claimed in claim 7, it is characterized in that, when an external signal that is input to infrared receiver is a noise signal, the capacitor charging of automatic gain control (AGC) interface to wherein providing is provided described charge/discharge controller, controls the voltage of the described output signal Vagc of (AGC) interface to increase automatic gain.
9. infrared receiver as claimed in claim 7, it is characterized in that, when there not being external signal to be input to described infrared receiver, the described capacitor discharge of described automatic gain control (AGC) interface to wherein providing is provided described charge/discharge controller, controls the voltage of the described output signal Vagc of (AGC) interface to reduce described automatic gain.
10. infrared receiver as claimed in claim 7, it is characterized in that, when an external signal that is input to described infrared receiver is a normal signal, described charge/discharge controller makes the not charge or discharge of described capacitor that are provided with in described automatic gain control (AGC) interface, constant to keep described second Amplifier Gain.
Applications Claiming Priority (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR10-2003-0001127 | 2003-01-08 | ||
| KR1020030001130A KR100575351B1 (en) | 2003-01-08 | 2003-01-08 | Infrared-ray recceiver capable of removing noise |
| KR1020030001127 | 2003-01-08 | ||
| KR1020030001130 | 2003-01-08 | ||
| KR1020030001127A KR100576094B1 (en) | 2003-01-08 | 2003-01-08 | Infrared-ray recceiver |
| KR10-2003-0001130 | 2003-01-08 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1518246A true CN1518246A (en) | 2004-08-04 |
| CN1316766C CN1316766C (en) | 2007-05-16 |
Family
ID=34315795
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2004100001994A Expired - Lifetime CN1316766C (en) | 2003-01-08 | 2004-01-06 | Infrared receiver |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN1316766C (en) |
| TW (1) | TWI240501B (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1983876B (en) * | 2005-12-15 | 2010-06-16 | Ad技术有限公司 | An infrared-ray receiver |
| CN101859486A (en) * | 2009-04-10 | 2010-10-13 | Ad技术有限公司 | An infrared-ray receiver having a gain control unit of mode transformation type |
| US8126088B2 (en) | 2008-12-04 | 2012-02-28 | Beken Corporation | Demodulator with signal preconditioner |
| CN102546002A (en) * | 2010-12-14 | 2012-07-04 | 无锡华润矽科微电子有限公司 | Infrared receiving circuit |
| CN104530781A (en) * | 2014-12-24 | 2015-04-22 | 常熟市亨达电子器材厂 | Mining infrared receiver |
| CN105869382A (en) * | 2015-02-10 | 2016-08-17 | 东莞德可森电子科技有限公司 | Infrared remote control receiver |
| CN106941358A (en) * | 2017-01-23 | 2017-07-11 | 厦门思力科电子科技有限公司 | A kind of infrared radiation receiving circuit with fast charge mode |
| CN109709559A (en) * | 2017-10-26 | 2019-05-03 | 奥特润株式会社 | Ultrasonic sensor and its control method |
| CN112671422A (en) * | 2020-12-24 | 2021-04-16 | 广州市慧芯电子科技有限公司 | Infrared receiving chip with reusable test port |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2151487A1 (en) * | 1993-10-28 | 1995-05-04 | Joshua Zhu | Remote control system, lighting system and filter |
| US5548833A (en) * | 1994-06-03 | 1996-08-20 | Transwitch Corporation | Data independent automatic gain control circuit for telecommunication applications |
| US5781588A (en) * | 1994-11-10 | 1998-07-14 | Matsushita Electric Industrial Co., Ltd. | FSK signal receiver |
| KR200179443Y1 (en) * | 1999-10-21 | 2000-04-15 | 주식회사에이디텍 | Infrared receiver |
-
2003
- 2003-12-31 TW TW92137623A patent/TWI240501B/en not_active IP Right Cessation
-
2004
- 2004-01-06 CN CNB2004100001994A patent/CN1316766C/en not_active Expired - Lifetime
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1983876B (en) * | 2005-12-15 | 2010-06-16 | Ad技术有限公司 | An infrared-ray receiver |
| US8126088B2 (en) | 2008-12-04 | 2012-02-28 | Beken Corporation | Demodulator with signal preconditioner |
| CN101859486A (en) * | 2009-04-10 | 2010-10-13 | Ad技术有限公司 | An infrared-ray receiver having a gain control unit of mode transformation type |
| CN101859486B (en) * | 2009-04-10 | 2012-07-04 | Ad技术有限公司 | An infrared-ray receiver having a gain control unit of mode transformation type |
| CN102546002A (en) * | 2010-12-14 | 2012-07-04 | 无锡华润矽科微电子有限公司 | Infrared receiving circuit |
| CN102546002B (en) * | 2010-12-14 | 2014-09-24 | 无锡华润矽科微电子有限公司 | Infrared receiving circuit |
| CN104530781A (en) * | 2014-12-24 | 2015-04-22 | 常熟市亨达电子器材厂 | Mining infrared receiver |
| CN105869382A (en) * | 2015-02-10 | 2016-08-17 | 东莞德可森电子科技有限公司 | Infrared remote control receiver |
| CN106941358A (en) * | 2017-01-23 | 2017-07-11 | 厦门思力科电子科技有限公司 | A kind of infrared radiation receiving circuit with fast charge mode |
| CN106941358B (en) * | 2017-01-23 | 2019-05-14 | 厦门思力科电子科技有限公司 | A kind of infrared radiation receiving circuit with fast charge mode |
| CN109709559A (en) * | 2017-10-26 | 2019-05-03 | 奥特润株式会社 | Ultrasonic sensor and its control method |
| CN109709559B (en) * | 2017-10-26 | 2023-12-26 | 现代摩比斯株式会社 | Ultrasonic sensor and control method thereof |
| CN112671422A (en) * | 2020-12-24 | 2021-04-16 | 广州市慧芯电子科技有限公司 | Infrared receiving chip with reusable test port |
Also Published As
| Publication number | Publication date |
|---|---|
| TW200514367A (en) | 2005-04-16 |
| CN1316766C (en) | 2007-05-16 |
| TWI240501B (en) | 2005-09-21 |
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Effective date of registration: 20190104 Address after: North Chungcheong Province Patentee after: ADTECH Co.,Ltd. Address before: Chungbei Qingzhou City, South Korea Patentee before: AD TECH Co.,Ltd. |
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