CN103457619A - Digital tuning receiving device and control method thereof - Google Patents
Digital tuning receiving device and control method thereof Download PDFInfo
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- CN103457619A CN103457619A CN2013103093840A CN201310309384A CN103457619A CN 103457619 A CN103457619 A CN 103457619A CN 2013103093840 A CN2013103093840 A CN 2013103093840A CN 201310309384 A CN201310309384 A CN 201310309384A CN 103457619 A CN103457619 A CN 103457619A
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Abstract
The invention provides a digital tuning receiving device. The digital tuning receiving device comprises an analog-digital converter, a real-time digital processing logic, a digital-to-analog converter and a low pass filter, wherein the analog-digital converter is used for quantization, the real-time digital processing logic is used for filtering and frequency converting, the digital-to-analog converter is used for converting a processed real-time digital intermediate frequency signal to an analog intermediate frequency signal, and the low pass filter is used for filtering out an image frequency component. The digital tuning receiving device is achieved by adopting a digital method, the stability is good, and by means of the digital tuning and digital filtering method, any intermediate frequency can be output, a ghost signal is prevented from occurring, intermediate frequency bandwidth can be changed at random, and the selectivity and out-of-band rejection capability of intermediate filtering are improved.
Description
Technical field
The present invention relates to electronic technology field, particularly a kind of digital tuning receiving system, also relate to a kind of control method of digital tuning receiving system.
Background technology
Tuner is mainly used in radiofrequency signal is converted on required intermediate frequency, comprises the functions such as amplification, frequency conversion, filtering.Tuner is widely used in fields such as radar, communication, electronic reconnaissance, environmental monitoring, thermometricallies.
It is one of critical function of tuned receiver that the RF/Microwave signal is become to intermediate-freuqncy signal output, and typical output IF-FRE commonly used has 10.7MHz, 21.4MHz, 70MHz, 140MHz, 160MHz etc.As shown in Figure 1, in this scheme, common the first local oscillator is tunable oscillator LO to typical tuning reception programme schematic diagram
1, through the first frequency converter, by input signal frequency conversion fixed intermediate frequency, this IF-FRE is called the first intermediate frequency F
iF1.The second local oscillator is fixed oscillator LO
2, through the second frequency converter by the first intermediate frequency (F
iF1) signal is converted on a certain fixed intermediate frequency frequency again, then externally exports this intermediate-freuqncy signal F
iFout.In order to obtain tuning receptivity preferably, this scheme adopts repeatedly conversion system usually.The intermediate frequency output of this receiver is fixed, and can't realize any IF-FRE output, the bandwidth varying filtering that more can't realize exporting intermediate frequency.
In order to realize any intermediate frequency output, existing common technology scheme is that the technical scheme shown in Fig. 1 is modified into to the technical scheme shown in Fig. 2, and the second local oscillator is designed to tunable oscillator F
lO2', the tuned frequency of the second local oscillator is F
lO2'=F
iFout± F
iF1.In order to realize F
iFoutthe filtering of signal can also increase a tunable bandpass filters after the second intermediate frequency amplifier, and the centre frequency of this filter is along with F
iFoutdifference and change, filter bandwidht is intermediate frequency output bandwidth B
iF.Technical scheme shown in Fig. 2 adopts analog circuit to realize, the circuit structure complexity, and poor stability, can produce a large amount of glitches, and the common selectivity of tunable optic filter and Out-of-band rejection ability are poor in addition, and can't realize the variable arbitrarily of intermediate-frequency bandwidth.
Summary of the invention
The invention discloses a kind of digital tuning receiving system and control method thereof, having solved receiver intermediate frequency output frequency can't adjust arbitrarily, the problem that output intermediate-frequency bandwidth can't change flexibly.
Technical scheme of the present invention is achieved in that
A kind of digital tuning receiving system, comprise: for the analog to digital converter quantized, carry out the real-time digital processing logic of filtering and frequency conversion, for the real-time digital intermediate-freuqncy signal by after processing, convert the digital to analog converter of analog if signal to and for the low pass filter of filtering image frequency component; The first digital copy in described real-time digital processing logic is shaken, will to receive signal frequency conversion be zero intermediate frequency signals for the first frequency mixer and the second frequency mixer, first many speed of adaptive-bandwidth digital filter and second many speed of adaptive-bandwidth digital filter carry out filtering to zero intermediate frequency signals, and the first fader and the second fader carry out gain-adjusted to zero intermediate frequency signals; The second digital copy is shaken, three-mixer and the 4th frequency mixer are up-converted into zero intermediate frequency signals the digital medium-frequency signal of output; Adder is by the two paths of signals sum operation generated after three-mixer and the 4th frequency mixer mixing; Control unit controls that the first digital copy is shaken and two duplicates shaking of the second digital copy shake signal output frequency, control the bandwidth of the first bandwidth varying wave digital lowpass filter and the second bandwidth varying wave digital lowpass filter, control the amount of gain of the first fader and the second fader.
Alternatively, generate the two-way orthogonal signalling after described the first frequency mixer and the second frequency mixer mixing.
Alternatively, described first many speed of bandwidth varying wave digital lowpass filter is the digital filter that two-way is identical with second many speed of bandwidth varying wave digital lowpass filter.
Alternatively, described first many speed of bandwidth varying wave digital lowpass filter and second many speed of bandwidth varying wave digital lowpass filter adopt the filtering extraction structure.
Alternatively, described first many speed of bandwidth varying wave digital lowpass filter and second many speed of bandwidth varying wave digital lowpass filter adopt the interpolation filtering structure.
Alternatively, described first many speed of bandwidth varying wave digital lowpass filter and second many speed of bandwidth varying wave digital lowpass filter adopt the variable coefficient filter structure.
The present invention also provides a kind of control method, is applicable to above-mentioned digital tuning receiving system, comprises the following steps:
Step (a), according to tuning frequency input signal, the output signal frequency that the first digital copy is shaken is arranged to identical with frequency input signal;
Step (b), configure the parameter of first many speed of bandwidth varying digital filter and second many speed of bandwidth varying digital filter according to required output intermediate-frequency bandwidth, first many speed of bandwidth varying digital filter is identical with the parameter that second many speed of bandwidth varying digital filter arranges;
Step (c), according to the gain requirement of tuning filtering, arrange the first fader and the second fader;
Step (d), the IF-FRE value of tuning operation as required, the output signal frequency that the second digital copy is shaken is arranged to export IF-FRE identical;
Step (e), start to process, complete by frequency input signal be tuned to the output of IF-FRE.
The invention has the beneficial effects as follows: adopt digital form to realize, good stability, adopt digital tuning and digital filtering mode, not only can realize any intermediate frequency output, avoided the glitch generation, can also realize exporting the variable arbitrarily of intermediate-frequency bandwidth, improve selectivity and the Out-of-band rejection ability of intermediate frequency filtering.
The accompanying drawing explanation
In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, below will the accompanying drawing of required use in embodiment or description of the Prior Art be briefly described, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain according to these accompanying drawings other accompanying drawing.
The control block diagram that Fig. 1 is existing tuning receiving system;
The control block diagram of the tuning receiving system that Fig. 2 is existing any intermediate frequency output;
The control block diagram that Fig. 3 is digital tuning receiving system of the present invention.
embodiment
Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is clearly and completely described, obviously, described embodiment is only the present invention's part embodiment, rather than whole embodiment.Embodiment based in the present invention, those of ordinary skills, not making under the creative work prerequisite the every other embodiment obtained, belong to the scope of protection of the invention.
As shown in Figure 3, the digital tuning receiving system that the present invention proposes comprises: for by inner certain the one-level intermediate-freuqncy signal f of superheterodyne reception measuring instrument
mthe analog to digital converter 2 quantized, carry out the real-time digital processing logic 15 of filtering and Up/Down Conversion, for the real-time digital intermediate-freuqncy signal by after processing, converts the digital to analog converter 12 of analog if signal to and for the low pass filter 13 of filtering image frequency component.Wherein shake the 4, first frequency mixer 51 and the second frequency mixer 52 of the first digital copy in real-time digital processing logic 15 is zero intermediate frequency signals for receiving signal frequency conversion, first many speed of adaptive-bandwidth digital filter 61 and 62 pairs of zero intermediate frequency signals of second many speed of adaptive-bandwidth digital filter are carried out filtering, and the first fader 71 and the second fader 72 are for carrying out gain-adjusted to zero intermediate frequency signals.The second digital copy shakes 8, three-mixer 91 and the 4th frequency mixer 92 be for being up-converted into zero intermediate frequency signals the digital medium-frequency signal f of output
0.Control unit 10 is for the 4 and second digital copy that the first digital copy is shaken shake control of signal output frequency of two duplicates of 8 of shaking, simultaneously also for controlling the bandwidth of the first bandwidth varying wave digital lowpass filter 61 and the second bandwidth varying wave digital lowpass filter 62, also for controlling the amount of gain of the first fader 71 and the second fader 72.
The input 1 of this device can be gathered by ADC transducer 2 for a certain fixed intermediate frequency signal in the superhet frequency conversion system, becomes zero intermediate frequency signals 3.This zero intermediate frequency signals 3 is divided into two-way and enters the first frequency mixer 51 and the second frequency mixer 52, with shake 4 signal of the first frequency controlled digital copy, carries out mixing, and the first digital copy is shaken and 4 is called NCO1.The first digital copy shakes 4, and by controlling, can to produce frequency be f
mmultiple sinusoidal signal sequence 41 and multiple sinusoidal signal sequence 42, be respectively cos (2 π f
mn) and-jsin (2 π f
mn).The signal of the two-way quadrature obtained after mixing, be called I road signal and Q road signal.The two paths of signals of 62 pairs of the first frequency mixers 51 of the first bandwidth varying wave digital lowpass filter 61 and the second bandwidth varying wave digital lowpass filter and the second frequency mixer 52 outputs carries out filtering, completes the intermediate-frequency bandwidth filtering needed.The first fader 71 and the second fader 72 are respectively to the adjustment that gains of filtered signal 611 and signal 612.Shake 8 signal of two paths of signals after gain is adjusted and the second frequency controlled digital copy carries out mixing.The second digital copy is shaken and 8 is called NCO2, and by controlling, can to produce frequency be f for it
0multiple sinusoidal signal sequence 81 and multiple sinusoidal signal sequence 82, be respectively cos (2 π f
0n) and-jsin (2 π f
0n).Wherein, frequency f
0be the intermediate-freuqncy signal frequency that needs output.The two paths of signals generated after mixing is respectively signal 911 and signal 912.Adder 11 is for carrying out sum operation to signal 911 and signal 912, and the burst obtained becomes analog if signal by DAC transducer 12.Low pass filter 13 carries out filtering for the analog if signal to converting to, and the filtering image frequency signal obtains the final analog if signal 14 of exporting.Control unit 10 is for controlling the first digital copy shake output frequency value of 8 of the 4 and second digital copy of shaking, also for controlling the bandwidth of the first bandwidth varying wave digital lowpass filter 61 and the second bandwidth varying wave digital lowpass filter 62, also for controlling the amount of gain of the first fader 71 and the second fader 72.Wherein first many speed of bandwidth varying wave digital lowpass filter 61 is digital filters that two-way is identical with second many speed of bandwidth varying wave digital lowpass filter 62, one of effect is to realize required intermediate-frequency bandwidth filtering, two of effect is output data rates, thereby the speed of output data rate and DAC conversion is complementary, identical with the speed of DAC conversion.This filter is not limited to the one-level filter, can require and the structures realizations such as the filtering of input and output rate requirement selecting extraction, interpolation filtering or variable coefficient filtering according to intermediate-frequency bandwidth.The digital processing part of the digital tuning filtering device of the present invention can adopt universal programmable chips to realize.
The present invention gives the control method of above-mentioned digital tuning filtering device, comprises the following steps:
Step (a), according to tuning frequency input signal f
m, shake 4 output signal frequency of the first digital copy is arranged to f
m, identical with frequency input signal;
Step (b), configure the parameter of first many speed of bandwidth varying digital filter 61 and second many speed of bandwidth varying digital filter 62 according to required output intermediate-frequency bandwidth, first many speed of bandwidth varying digital filter 61 is identical with the parameter that second many speed of bandwidth varying digital filter 62 arranges;
Step (c), according to the gain requirement of tuning filtering, arrange the first fader 71 and the second fader 72;
Step (d), the IF-FRE value f of tuning operation as required
0, shake 8 output signal frequency of the second digital copy is arranged to f
0, identical with the output IF-FRE;
Step (e), start and process, and can complete frequency input signal f
mbe tuned to IF-FRE be f
0output;
Step (f), when the output IF-FRE changes, reset to (e) according to step (a).
Digital tuning receiving system of the present invention and control method adopt digital form to realize, good stability, adopt digital tuning and digital filtering mode, not only can realize any intermediate frequency output, avoided the glitch generation, can also realize exporting the variable arbitrarily of intermediate-frequency bandwidth, improve selectivity and the Out-of-band rejection ability of intermediate frequency filtering.
The foregoing is only preferred embodiment of the present invention, in order to limit the present invention, within the spirit and principles in the present invention not all, any modification of doing, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.
Claims (7)
1. a digital tuning receiving system, it is characterized in that, comprise: for the analog to digital converter quantized, carry out the real-time digital processing logic of filtering and frequency conversion, for the real-time digital intermediate-freuqncy signal by after processing, convert the digital to analog converter of analog if signal to and for the low pass filter of filtering image frequency component;
Described real-time digital processing logic comprises: the first digital copy is shaken, the first frequency mixer and the second frequency mixer, and will receive signal frequency conversion is zero intermediate frequency signals; First many speed of adaptive-bandwidth digital filter and second many speed of adaptive-bandwidth digital filter carry out filtering to zero intermediate frequency signals; The first fader and the second fader carry out gain-adjusted to zero intermediate frequency signals; The second digital copy is shaken, three-mixer and the 4th frequency mixer are up-converted into zero intermediate frequency signals the digital medium-frequency signal of output; Adder is by the two paths of signals sum operation generated after three-mixer and the 4th frequency mixer mixing; Control unit controls that the first digital copy is shaken and two duplicates shaking of the second digital copy shake signal output frequency, control the bandwidth of the first bandwidth varying wave digital lowpass filter and the second bandwidth varying wave digital lowpass filter, control the amount of gain of the first fader and the second fader.
2. a kind of digital tuning receiving system as claimed in claim 1, is characterized in that, generates the two-way orthogonal signalling after described the first frequency mixer and the second frequency mixer mixing.
3. a kind of digital tuning receiving system as claimed in claim 2, is characterized in that, described first many speed of bandwidth varying wave digital lowpass filter is the digital filter that two-way is identical with second many speed of bandwidth varying wave digital lowpass filter.
4. a kind of digital tuning receiving system as claimed in claim 3, is characterized in that, described first many speed of bandwidth varying wave digital lowpass filter and second many speed of bandwidth varying wave digital lowpass filter adopt the filtering extraction structure.
5. a kind of digital tuning receiving system as claimed in claim 3, is characterized in that, described first many speed of bandwidth varying wave digital lowpass filter and second many speed of bandwidth varying wave digital lowpass filter adopt the interpolation filtering structure.
6. a kind of digital tuning receiving system as claimed in claim 3, is characterized in that, described first many speed of bandwidth varying wave digital lowpass filter and second many speed of bandwidth varying wave digital lowpass filter adopt the variable coefficient filter structure.
7. a control method, be applicable to the described digital tuning receiving system of claim 1 to 6 any one, it is characterized in that, comprises the following steps:
Step (a), according to tuning frequency input signal, the output signal frequency that the first digital copy is shaken is arranged to identical with frequency input signal;
Step (b), configure the parameter of first many speed of bandwidth varying digital filter and second many speed of bandwidth varying digital filter according to required output intermediate-frequency bandwidth, first many speed of bandwidth varying digital filter is identical with the parameter that second many speed of bandwidth varying digital filter arranges;
Step (c), according to the gain requirement of tuning filtering, arrange the first fader and the second fader;
Step (d), the IF-FRE value of tuning operation as required, the output signal frequency that the second digital copy is shaken is arranged to export IF-FRE identical;
Step (e), start to process, complete by frequency input signal be tuned to the output of IF-FRE.
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| CN105490691A (en) * | 2014-09-19 | 2016-04-13 | 成都振芯科技股份有限公司 | Bandwidth-adjustable zero-intermediate-frequency narrow-band receiving circuit |
| CN105490692A (en) * | 2014-09-19 | 2016-04-13 | 成都振芯科技股份有限公司 | Bandwidth-adjustable zero-intermediate-frequency narrow-band receiving processing method |
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| CN105490692A (en) * | 2014-09-19 | 2016-04-13 | 成都振芯科技股份有限公司 | Bandwidth-adjustable zero-intermediate-frequency narrow-band receiving processing method |
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| CN103457619B (en) | 2016-12-28 |
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Effective date of registration: 20190312 Address after: 266000 No. 98 Xiangjiang Road, Huangdao District, Qingdao City, Shandong Province Patentee after: China Electronics Technology Instrument and Meter Co., Ltd. Address before: 266555 No. 98 Xiangjiang Road, Qingdao economic and Technological Development Zone, Shandong Patentee before: The 41st Institute of CETC |
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Address after: Huangdao Xiangjiang Road 266555 Shandong city of Qingdao Province, No. 98 Patentee after: CLP kesiyi Technology Co.,Ltd. Address before: 266000 No. 98 Xiangjiang Road, Huangdao District, Shandong, Qingdao Patentee before: CHINA ELECTRONIC TECHNOLOGY INSTRUMENTS Co.,Ltd. |
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