CN104539261A - Arbitrary sampling rate conversion interpolation filtering processing method - Google Patents
Arbitrary sampling rate conversion interpolation filtering processing method Download PDFInfo
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- CN104539261A CN104539261A CN201410745446.7A CN201410745446A CN104539261A CN 104539261 A CN104539261 A CN 104539261A CN 201410745446 A CN201410745446 A CN 201410745446A CN 104539261 A CN104539261 A CN 104539261A
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Abstract
The invention relates to an arbitrary sampling rate conversion interpolation filtering processing method. The method comprises a first step of generating a finite impulse response (FIR) filter tap coefficient table according to a bandwidth requirement and a filtering precision coefficient of an input signal; a second step of generating a doubled data clock signal by a numerically controlled oscillator (NCO), and acquiring a clock phase-Phase of the clock signal; a third step of receiving a signal by the doubled data clock signal; a fourth step of extracting corresponding filtering coefficient from the FIR filter coefficient table according to the clock phase-Phase; and a fifth step of applying the extracted filtering coefficient in the FIR filter, filtering the received signal, so as to convert the sampling rate of the input signal into system working frequency fs to realize sampling rate conversion interpolation filtering processing. An interpolation filter in the method comprises a transverse FIR filter and a read only memory (ROM) table with the filter coefficient, thereby being simple to realize, costing few hardware source, and having strong practicability.
Description
Technical field
The present invention relates to digital filtering technique field, particularly a kind of interpolation filtering processing method of any sample rate conversion.
Background technology
In existing digital interpolation design of filter, signal sampling rate is changed to system works clock, in order to adapt to the variable requirement of data rate, a kind of method is the speed according to transmission data, employing reconfigures clock chip to change DA work clock, and this method limits by hardware platform; Another method adopts multiple filter to carry out integral multiple filtering interpolation for specific several speed, and this method filter order is many, complex structure, consumes resources are huge, and data rate can not continuous variable, and practicality is not strong.
Summary of the invention
The object of the invention is to overcome the deficiencies in the prior art, provide a kind of interpolation filtering processing method of any sample rate conversion, the interpolation filter adopted in the method is shown to form by the ROM of filter coefficient by a horizontal FIR filter and a bookbinding, within each system works clock fs cycle, interpolation filter coefficient table is searched according to the clock phase phase after quantizing, real-time update FIR filter coefficient also carries out filtering operation, obtaining sample rate is signal after the interpolation of fs, this interpolation filtering method realizes simple, expend hardware resource few, practical.
Above-mentioned purpose of the present invention is mainly achieved by following technical solution:
An interpolation filtering processing method for any sample rate conversion, comprises the following steps:
1, an interpolation filtering processing method for any sample rate conversion, is characterized in that comprising the following steps:
(1), according to the bandwidth B w of input signal and the signal resolution parameter K of setting, generate K group FIR filter coefficient, and described K group filter coefficient is kept in FIR filter tap coefficient table; Wherein, described signal resolution parameter K=2
l, L is positive integer;
(2), according to code check Rb and the system clock frequency fs of input signal, NCO is adopted to produce 1 haplotype data clock signal, the frequency Rs=Rb of described data clock signal, the clock phase Phase of described data clock signal equals the high L position intercepting value of described NCO accumulated value, and namely the span of described clock phase Phase is 0 ~ K-1; Wherein, the bit wide of described NCO is M and M >=L;
(3) the 1 haplotype data clock signal, according to step (2) produced receives input signal, obtains Received signal strength;
(4), according to the value of the clock phase Phase of Signal reception clock, the tap coefficient of FIR filter is extracted in the FIR filter tap coefficient table that step (1) produces, wherein, if described clock phase Phase=k-1, then in described FIR filter tap coefficient table extract obtain kth group low-pass FIR filter coefficient h '
k(n), wherein, k=1,2 ..., K, n=1,2 ..., N, N are the tap number of described FIR filter;
(5), by step (4) extracting the FIR filter coefficient obtained is applied in FIR filter, carries out interpolation filtering process to the Received signal strength obtained in step (3), obtains signal after interpolation filtering.
The interpolation filtering processing method of above-mentioned any sample rate conversion, in step (1), according to the bandwidth B w of input signal and the signal resolution parameter K of setting, generate K group FIR filter coefficient, and described K group filter coefficient is kept in FIR filter tap coefficient table, specific implementation process is as follows:
(1a), according to signal bandwidth Bw, tap coefficient h (n) that a group meets the FIR filter of filtering requirements in described signal bandwidth is generated, wherein, n=1,2 ..., N, N are the tap number of described FIR filter;
(1b), according to the signal resolution parameter K of setting obtain K proportion function, wherein, a kth described proportion function is
k=1,2 ..., K, n=1,2 ..., N;
(1c), leaf transformation in N point discrete Fourier is carried out to FIR filter tap coefficient h (n) that step (1a) obtains, obtain FIR filter response function H (jw)=DFT (h (n)), wherein, DFT () represents discrete Fourier transform; N number of value of described response function H (jw) is respectively h
1, h
2..., h
n..., h
n;
(1d) the response function H (jw) that K the proportion function, according to step (1b) obtained and step (1c) obtain, obtain K new response function, wherein, a kth described new response function is H '
k(jw), H '
k(jw) N number of value is respectively h
1', h
2' ..., h
n' ..., h
n', wherein, h
n'=h
n× f
k(n), k=1,2 ..., K, n=1,2 ..., N;
(1e) K the new response function, to step (1d) obtained carries out inverse Fourier transform and obtains K group filter coefficient, and wherein, filter coefficient described in kth group is h '
k(n)=IDFT (H '
k(jw)), IDFT represents inverse discrete Fourier transform, k=1, and 2 ..., K;
(1f), K group filter coefficient will be obtained in step (1e) successively stored in tables of data, obtain FIR filter tap coefficient table.
The interpolation filtering processing method of above-mentioned any sample rate conversion, the bookbinding of FIR filter tap coefficient table is in ROM table.
The present invention's advantage is compared with prior art:
(1), the present invention has the ROM of filter coefficient to form fraction double interpolation filter by a horizontal FIR filter and a bookbinding, the sample rate that can be realized different rates signal by this fraction double interpolation filter by signal frequency to system operating frequency sample rate conversion, implementation structure is simple, and the continuous variable requirement of input signal can be met, practical.
(2) fraction double interpolation filter of the present invention is shown to form by the ROM of filter coefficient by a horizontal FIR filter and a bookbinding, within each system works clock fs cycle, internal filter coefficients table is searched according to the clock phase phase after quantizing, real-time update FIR filter coefficient also carries out filtering operation, and obtaining sample rate is signal after the interpolation of fs.This filter implementation method is simple, and hardware resource used is few, effectively can overcome that prior art is simple by the interpolation filter structure in hardware platform restriction, the inventive method, operand is little;
(3) the ROM table size of the bookbinding filter coefficient used in the present invention can adjust flexibly according to the requirement of input signal resolution, can meet performance requirement, again can saving resource, and flexibility is strong.
Accompanying drawing explanation
Fig. 1 is the process flow block diagram of interpolation filtering processing method of the present invention.
Embodiment
Below in conjunction with the drawings and specific embodiments, the present invention is described in further detail:
Shown in process flow block diagram of the present invention as shown in Figure 1, the interpolation filtering processing method of any sample rate conversion of the present invention, comprises the following steps:
(1), according to the bandwidth B w of input signal and the signal resolution parameter K of setting, generate K group FIR filter coefficient, and described K group filter coefficient is kept in FIR filter tap coefficient table; Wherein, described signal resolution parameter K=2
l, L is positive integer; Specific implementation step is as follows:
(1a), according to signal bandwidth Bw, tap coefficient h (n) that a group meets the FIR filter of filtering requirements in described signal bandwidth is generated, wherein, n=1,2 ..., N, N are the tap number of described FIR filter;
(1b), according to the quality coefficient K of setting obtain K proportion function, wherein, a kth described proportion function is
k=1,2 ..., K, n=1,2 ..., N;
(1c), leaf transformation in N point discrete Fourier is carried out to FIR filter tap coefficient h (n) that step (1a) obtains, obtain FIR filter response function H (jw)=DFT (h (n)), wherein, DFT () represents discrete Fourier transform; N number of value of described response function H (jw) is respectively h
1, h
2..., h
n..., h
n;
(1d) the response function H (jw) that K the proportion function, according to step (1b) obtained and step (1c) obtain, obtain K new response function, wherein, a kth described new response function is H '
k(jw), H '
k(jw) N number of value is respectively h
1', h
2' ..., h
n' ..., h
n', wherein, h
n'=h
n× f
k(n), k=1,2 ..., K, n=1,2 ..., N;
(1e) K the new response function, to step (1d) obtained carries out inverse Fourier transform and obtains K group filter coefficient, and wherein, filter coefficient described in kth group is h '
k(n)=IDFT (H '
k(jw)), IDFT represents inverse discrete Fourier transform, k=1, and 2 ..., K;
(1f), K group filter coefficient will be obtained in step (1e) successively stored in tables of data, obtain FIR filter tap coefficient table, this FIR filter tap coefficient table can be bound and be shown at ROM, be convenient to hardware implementing, can with horizontal FIR filter conbined usage, realize the filtering interpolation process of variable sampling rate.
In the present embodiment, FIR filter is set as the transversal filter on 32 rank, namely has 32 delay cells, altogether N=33 tap coefficient; And the signal resolution parameter K=256 of setting, i.e. positive integer L=8;
(2), according to code check Rb and the system clock frequency fs of input signal, NCO is adopted to produce 1 haplotype data clock signal, the frequency Rs=Rb of described data clock signal, the clock phase Phase of described data clock signal equals the high L position intercepting value of described NCO accumulated value, and namely the span of described clock phase Phase is 0 ~ K-1; Wherein, the bit wide of described NCO is M and M >=L; The operating frequency of this NCO is fs;
In the present embodiment, the bit wide of NCO is M=32, and when the input signal resolution parameter K=256 set, clock phase phase is the most-significant byte intercepting value of NCO accumulated value, and that is the value of clock phase is 0 ~ 255; In the present invention, adopt this clock phase to obtain the extraction sequence number of FIR filter coefficient exactly, the coefficient realizing filtering interpolation extracts.
(3) the 1 haplotype data clock signal, according to step (2) produced receives input signal, obtains Received signal strength; Namely the sample rate of this Received signal strength is Rs, and object of the present invention is exactly be converted to systematic sampling rate by unified for the sample rate of this signal, and ensures that signal is undistorted;
(4), according to the value of the phase place Phase of Signal reception clock, the tap coefficient of FIR filter is extracted in the FIR filter tap coefficient table that step (1) produces, wherein, if described clock phase Phase=k-1, then in described FIR filter tap coefficient table extract obtain kth group low-pass FIR filter coefficient h '
k(n), wherein, k=1,2 ..., K, n=1,2 ..., N, N are the tap number of described FIR filter;
(5), step (4) being extracted the FIR filter coefficient obtained is applied in FIR filter, interpolation filtering process is carried out to the Received signal strength obtained in step (3), obtain signal after interpolation filtering, the sample rate of this signal is fs, namely be that the Interpolation of signals of Rs is filtered into the signal that sample rate is fs through to process sample rate above, thus realize the conversion of sample rate.
In the present embodiment, interpolation filter of the present invention is shown to form by the ROM of filter coefficient by a horizontal FIR filter in 32 rank and a bookbinding.Within each system works clock fs cycle, according to the clock phase phase after quantizing, in ROM table, search filter coefficient, real-time update FIR filter coefficient also carries out filtering operation, and obtaining sample rate is signal after the interpolation of fs.If quantized by 16 each filter factor, clock phase phase quantizes by 8, then the memory space of binding the ROM table of FIR filter coefficient is 33*16*2
8=135168bit.
The present invention adopts the fraction double interpolation filter of variable coefficient, realizes the filtering of different rates signal interpolation, and whole function can adopt FPGA to realize.
The above; be only the embodiment of the best of the present invention, but protection scope of the present invention is not limited thereto, is anyly familiar with those skilled in the art in the technical scope that the present invention discloses; the change that can expect easily or replacement, all should be encompassed within protection scope of the present invention.
The content be not described in detail in specification of the present invention belongs to professional and technical personnel in the field's known technology.
Claims (3)
1. an interpolation filtering processing method for any sample rate conversion, is characterized in that comprising the following steps:
(1), according to the bandwidth B w of input signal and the signal resolution parameter K of setting, generate K group FIR filter coefficient, and described K group filter coefficient is kept in FIR filter tap coefficient table; Wherein, described signal resolution parameter K=2
l, L is positive integer;
(2), according to code check Rb and the system clock frequency fs of input signal, NCO is adopted to produce 1 haplotype data clock signal, the frequency Rs=Rb of described data clock signal, the clock phase Phase of described data clock signal equals the high L position intercepting value of described NCO accumulated value, and namely the span of described clock phase Phase is 0 ~ K-1; Wherein, the bit wide of described NCO is M and M >=L;
(3) the 1 haplotype data clock signal, according to step (2) produced receives input signal, obtains Received signal strength;
(4), according to the value of the clock phase Phase of Signal reception clock, the tap coefficient of FIR filter is extracted in the FIR filter tap coefficient table that step (1) produces, wherein, if described clock phase Phase=k-1, then in described FIR filter tap coefficient table extract obtain kth group low-pass FIR filter coefficient h '
k(n), wherein, k=1,2 ..., K, n=1,2 ..., N, N are the tap number of described FIR filter;
(5), by step (4) extracting the FIR filter coefficient obtained is applied in FIR filter, carries out interpolation filtering process to the Received signal strength obtained in step (3), obtains signal after interpolation filtering.
2. the interpolation filtering processing method of a kind of any sample rate conversion according to claim 1, it is characterized in that: in step (1), according to the bandwidth B w of input signal and the signal resolution parameter K of setting, generate K group FIR filter coefficient, and described K group filter coefficient is kept in FIR filter tap coefficient table, specific implementation process is as follows:
(1a), according to signal bandwidth Bw, tap coefficient h (n) that a group meets the FIR filter of filtering requirements in described signal bandwidth is generated, wherein, n=1,2 ..., N, N are the tap number of described FIR filter;
(1b), according to the signal resolution parameter K of setting obtain K proportion function, wherein, a kth described proportion function is
k=1,2 ..., K, n=1,2 ..., N;
(1c), leaf transformation in N point discrete Fourier is carried out to FIR filter tap coefficient h (n) that step (1a) obtains, obtain FIR filter response function H (jw)=DFT (h (n)), wherein, DFT () represents discrete Fourier transform; N number of value of described response function H (jw) is respectively h
1, h
2..., h
n..., h
n;
(1d) the response function H (jw) that K the proportion function, according to step (1b) obtained and step (1c) obtain, obtain K new response function, wherein, a kth described new response function is H '
k(jw), H '
k(jw) N number of value is respectively h
1', h
2' ..., h
n' ..., h
n', wherein, h
n'=h
n× f
k(n), k=1,2 ..., K, n=1,2 ..., N;
(1e) K the new response function, to step (1d) obtained carries out inverse Fourier transform and obtains K group filter coefficient, and wherein, filter coefficient described in kth group is h '
k(n)=IDFT (H '
k(jw)), IDFT represents inverse discrete Fourier transform, k=1, and 2 ..., K;
(1f), K group filter coefficient will be obtained in step (1e) successively stored in tables of data, obtain FIR filter tap coefficient table.
3. the interpolation filtering processing method of a kind of any sample rate conversion according to claim 1, is characterized in that: the bookbinding of FIR filter tap coefficient table is in ROM table.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105306008A (en) * | 2015-11-13 | 2016-02-03 | 北京遥测技术研究所 | Interpolation filtering processing method of arbitrary sampling rate conversion |
| CN108366320A (en) * | 2018-01-08 | 2018-08-03 | 联创汽车电子有限公司 | Vehicle-mounted feedforward active noise reduction system |
| CN108871385A (en) * | 2017-05-12 | 2018-11-23 | 西门子公司 | Encoder, motor, encoder data processing method and storage medium |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1192609A (en) * | 1997-01-10 | 1998-09-09 | 哈里公司 | Re-sampling circuit and associated method |
| CN1226888C (en) * | 2001-09-07 | 2005-11-09 | 三星Thales株式会社 | Block interpolating filter structure using seeking table |
| CN103650445A (en) * | 2011-03-09 | 2014-03-19 | 联邦科学技术研究组织 | Arbitrary sample rate conversion for communication systems |
-
2014
- 2014-12-08 CN CN201410745446.7A patent/CN104539261B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1192609A (en) * | 1997-01-10 | 1998-09-09 | 哈里公司 | Re-sampling circuit and associated method |
| CN1226888C (en) * | 2001-09-07 | 2005-11-09 | 三星Thales株式会社 | Block interpolating filter structure using seeking table |
| CN103650445A (en) * | 2011-03-09 | 2014-03-19 | 联邦科学技术研究组织 | Arbitrary sample rate conversion for communication systems |
Non-Patent Citations (3)
| Title |
|---|
| 叶双应 等: ""一种用于符号同步的奈奎斯特滤波器优化设计"", 《电子器件》 * |
| 朱雪阳: ""基于Gardner算法的位定时同步研究"", 《中国优秀硕士学位论文全文数据库 信息科技辑》 * |
| 杨霖: ""基于FPGA的EDSL系统QAM解调器的研究与实现"", 《中国优秀硕士学位论文全文数据库 信息科技辑》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105306008A (en) * | 2015-11-13 | 2016-02-03 | 北京遥测技术研究所 | Interpolation filtering processing method of arbitrary sampling rate conversion |
| CN108871385A (en) * | 2017-05-12 | 2018-11-23 | 西门子公司 | Encoder, motor, encoder data processing method and storage medium |
| CN108366320A (en) * | 2018-01-08 | 2018-08-03 | 联创汽车电子有限公司 | Vehicle-mounted feedforward active noise reduction system |
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