WO2001011785A2 - Kaskadierter sigma-delta-modulator - Google Patents
Kaskadierter sigma-delta-modulator Download PDFInfo
- Publication number
- WO2001011785A2 WO2001011785A2 PCT/DE2000/002604 DE0002604W WO0111785A2 WO 2001011785 A2 WO2001011785 A2 WO 2001011785A2 DE 0002604 W DE0002604 W DE 0002604W WO 0111785 A2 WO0111785 A2 WO 0111785A2
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- sigma
- delta modulator
- cascade
- signal
- delta
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M7/00—Conversion of a code where information is represented by a given sequence or number of digits to a code where the same, similar or subset of information is represented by a different sequence or number of digits
- H03M7/30—Compression; Expansion; Suppression of unnecessary data, e.g. redundancy reduction
- H03M7/3002—Conversion to or from differential modulation
- H03M7/3004—Digital delta-sigma modulation
- H03M7/3015—Structural details of digital delta-sigma modulators
- H03M7/302—Structural details of digital delta-sigma modulators characterised by the number of quantisers and their type and resolution
- H03M7/3022—Structural details of digital delta-sigma modulators characterised by the number of quantisers and their type and resolution having multiple quantisers arranged in cascaded loops, each of the second and further loops processing the quantisation error of the loop preceding it, i.e. multiple stage noise shaping [MASH] type
Definitions
- the invention relates to a cascaded sigma- delta modulator, in particular for converting time-discrete samples or samples m corresponding analog signals in digital radio communication reception devices, each with an error signal representing the quantization noise of a sigma-delta modulator of the cascade next sigma-delta modulator is fed to this cascade.
- a digital input signal with 2 "signal states and a fixed sampling frequency ⁇ is usually converted into an analog signal which is in the frequency range -f a / 2 to + f a / 2 should match the digital signal as well as possible.
- bit width n the number of signal states to be realized by analog circuit technology is a major problem.
- a digital signal is interpolated by digital filters, and so-called sigma-delta modulators are used that contain the bit width n significantly reduce the digital signal at an increased sampling frequency.
- the quantization noise generated in the process is transformed into previously unused frequency ranges. Structures that achieve a shaping of the noise signal by using a higher-order IIR filter (Infinite Impulse Response Filter) are particularly efficient for this.
- IIR filter Infinite Impulse Response Filter
- a digital-to-analog converter using an IIR filter as an interpoller element and one or more sigma-delta modulators for converting the interpolated signals is included. for example described in US 5 786 779.
- a cascaded sigma-delta modulator for a digital-to-analog converter is also shown in DE 197 22 434 Cl.
- a detailed Dar ⁇ position of the structure and mode of action of sigma-delta modulators is m SR Norswothy, R. Schreier and G. Temes:
- the invention has for its object to combine a sigma-delta modulator with the advantages of stability in operating behavior and the simpler feasibility of a cascaded approach with the advantages of a small number of stages of a higher order feedback loop.
- the task is characterized by
- the invention is based on a cascaded sig a delta modulator. By adding additional logic, the number of signal states is reduced to up to 2 - corresponding to 1 bit. Elaborate Clippmg circuits are not necessary without that the stability of the circuit would be endangered.
- the circuit is modular, can be an existing De ⁇ sign of a sigma-delta modulator order l.-ter by adding ⁇ add an additional stage in a circuit l + Procedure L. ter-m easily be converted.
- Another advantage of the invention is that the logic of a sigma-delta modulator, its decision maker and the additions of the decision output signals do not affect the lowermost bits of a number representation.
- Numerical values are usually coded as a sum of powers of two (e.g. two's complement representation).
- the sum terms that are larger in terms of the amount do not influence the result of the sum terms that are smaller in terms of the amount.
- the decision-maker output signal according to the exemplary embodiments according to the invention has a high numerical value. This does not affect the low-order sum elements (bits), which can be calculated very efficiently separately.
- the overflows resulting from the calculation, the decision-maker output signal and the high-quality part of the input signal of the sigma-delta modulator can then be calculated in a second part of a sigma-delta modulator.
- Fig. 4 A second exemplary embodiment
- Fig. 5 A linear replacement model to explain the second exemplary embodiment.
- a Sig ⁇ ma-delta modulator Ml 1st or 2nd order is used conventional execution. From a digital input signal sequence x ⁇ k), this generates on the one hand an output signal sequence y ⁇ k) with a small number of stages and on the other hand an error signal sequence e ⁇ k) representing the quantization noise.
- the error signal e ⁇ k is fed to the input of a second sigma-delta modulator M2.
- This generates a low-level replica of the signal e (k), which is spectrally shaped by a digital filter F2 such that the error e ⁇ k) at the output of a summer S1 is compensated and also a quantization error e_ (J), which affects the input of a third sigma-delta modulator M3.
- the summer S1 has two positive inputs, one positive input being connected to the output of the first sigma-delta modulator M1 and the second positive input being connected to the output of the digital filter F2 of the second sigma-delta modulator M2.
- the output of the summer S1 supplies the compensated signal y (Je) and is connected to the positive input of a further summer S2, to which the output signal of a digital filter F3 of a third sigma-delta modulator M3 is fed at a second positive input.
- Both the output signal of the second sigma-delta modulator M2 and the subsequent spectral shaping in the filter F2 increase the number of stages of the signal y ⁇ ⁇ k). The same happens analogously with the downstream sigma-delta modulator M3.
- the output signal of the 11 sigma-delta modulators fed to the decision-making process of the i-th sigma-delta modulator This is highlighted in Fig. 1 by the dashed lines.
- the output of the sigma-delta modulator Ml is additionally led to the decision input of the sigma-delta modulator M2 of the second stage and the output of the adder S1, to which the compensated signal y_ ⁇ k) is present, is additionally routed to the decision input of the third-stage sigma-delta modulator M3. It is within the scope of the invention to connect further sigma-delta modulators in this way.
- the output signals y - (k) of all preceding cascade stages can be fed to the decision maker of the i-th sigma-delta modulator of the cascade. This is shown in Fig. 1 for the third cascade stage M3 by the dotted connections from the output of the sigma-delta modulators M1, M2 to the decision input of the third sigma-delta modulator M3.
- FIG. 2 shows a cascaded second-order cascaded sigma-delta modulator with a two-stage output signal (1 bit).
- the first stage is a conventional first-order sigma-delta modulator Ml with a 1-bit output signal (-1, 1), which operates stably with an input signal x (Je) in the range: -1 ⁇ x ⁇ +1 which a decision maker El and a delay VI are referred to in more detail.
- the magnitude of the error signal e (Je) is always less than 1, so that an input signal limited in terms of number is available for the second stage.
- the A ⁇ output signal can of Figure 2 does not close the filter shown in the second sigma-delta modulator M2 are selected such that the output signal J (JE), the above-mentioned condition he ⁇ filled..
- the output signal J (JE) the above-mentioned condition he ⁇ filled..
- Fig. 2 the one function of the filter F2 of Fig. Ver with the function of the second sigma-delta modulator M2 ⁇ be linked.
- the output signal y ⁇ k) of the first sigma-delta modulator Ml is fed to the decision maker E2 of the second sigma-delta modulator M2 (dashed line), the output signal of the decision maker E2 is integrated into an integrator 12 and the integration result is approximated Signal compared.
- the integrator 12 and the decision maker E2 together form an expanded decision maker with the output signal y_ ⁇ k).
- the equations used for the decision-making process are for the output signal y ⁇ k) of the first stage:
- the integration result ⁇ Je) of the integrator takes 12 at the time Only one of the three numerical values (-2.0, +2).
- the integration result y 2 (k) is subtracted from the signal ⁇ A (Je) to be approximated and thus the approximation error e 2 (Je) is calculated.
- the delay element V2 delays the approximation error e_ (Je) by one clock cycle, so that in the next clock cycle it is added to the input signal of the second stage e (k + l) and the signal x : (k + l) is calculated.
- the first delta-sigma modulator Ml adds an error signal e (Je) representing the quantization noise to the original signal x (Je), which is high-pass-shaped in accordance with a first-order FIR filter (filter Dl).
- This error signal e (Je) also forms the input signal of the second sigma-delta modulator M2, which in turn adds a first-order colored quantization error signal.
- the spectral shaping of the error signal is shown by the filter D2 / 1. Due to the architecture of the second decision maker, not shown in FIG. 3, the differentiated output signal of the second sigma-delta modulator M2 at the differentiator D2 / 2 is available. It consists of the differentiated error signal of the first stage, which compensates for the error m y (k), and a second-order colored noise signal.
- FIG. 4 shows, as a further exemplary embodiment, a three-stage cascaded 3rd order sigma-delta modulator with the sigma-delta modulators M1 to M3 and a three-stage output signal y 3 (Jc) of 1.5 bits.
- the output signal y (A of the first sigma-delta modulator Ml is, in addition to a positive input of the summer S1, according to the invention to an input of the decision maker E2 of the second sigma-delta modulator M2 of analog design (dashed line) whose Output is led via a differentiator D2 to a second positive input of the summer S1, the error signal at the output of the summer S1 y 2 (Je) at which, in addition to a positive input of a Summie ⁇ RERS S2 to form the output error signal y k) erfm- dungsgebound decider also formed on the from the decision E3 and the integrator 13 of the third sigma-delta -Modulator M3 is led.
- a dither signal sequence r ⁇ k is added in the summer S3 for the purpose of suppressing discrete memories and is applied to the input of the third sigma-delta modulator M3.
- the output of the third sigma-delta modulator M3 is led via a differentiator D3 to the second positive input of the summer S2.
- the output signal y 3 ⁇ k) is present at the output of the summer S2 for further processing, for example amplification.
- FIG. 5 shows the imearized model of the modulator according to FIG. 4.
- the quantization error e 2 (Je) generated in the second sigma-delta modulator M2 is summed up in the summer S3 with a dither signal r (Je) and fed to the input of the third sigma-delta modulator M3.
- the output signal y (k) generated in the third sigma-delta modulator M3 is differentiated m D3 and added to the signal y 2 ⁇ k) m the summer S2 for the purpose of error compensation.
- the output of the third sigma-delta modulator M3 is led via a differentiator D3 to the second positive input of the summer S2.
- a low-level output signal sequence yA k) is present at the output of summer S2 for further processing, for example amplification.
Landscapes
- Engineering & Computer Science (AREA)
- Theoretical Computer Science (AREA)
- Compression, Expansion, Code Conversion, And Decoders (AREA)
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2001515542A JP2004500745A (ja) | 1999-08-06 | 2000-08-03 | カスケード・シグマデルタ変調器 |
US09/806,927 US6518904B1 (en) | 1999-08-06 | 2000-08-03 | Cascade sigma-delta modulator |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19937246A DE19937246B4 (de) | 1999-08-06 | 1999-08-06 | Kaskadierter Sigma-Delta-Modulator |
DE19937246.2 | 1999-08-06 |
Publications (2)
Publication Number | Publication Date |
---|---|
WO2001011785A2 true WO2001011785A2 (de) | 2001-02-15 |
WO2001011785A3 WO2001011785A3 (de) | 2001-09-27 |
Family
ID=7917507
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/DE2000/002604 WO2001011785A2 (de) | 1999-08-06 | 2000-08-03 | Kaskadierter sigma-delta-modulator |
Country Status (5)
Country | Link |
---|---|
US (1) | US6518904B1 (de) |
JP (1) | JP2004500745A (de) |
CN (1) | CN1135706C (de) |
DE (1) | DE19937246B4 (de) |
WO (1) | WO2001011785A2 (de) |
Families Citing this family (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1335494A1 (de) | 2001-12-19 | 2003-08-13 | Siemens Aktiengesellschaft | Sigma-Delta-Wandler mit Rauschunterdrückung |
DE10162565A1 (de) * | 2001-12-19 | 2003-07-17 | Siemens Ag | Breitbandiger Sigma-Delta-Modulator |
EP1333583A1 (de) | 2001-12-19 | 2003-08-06 | Siemens Aktiengesellschaft | Breitbandiger Sigma-Delta-Modulator |
US6842128B2 (en) * | 2003-02-28 | 2005-01-11 | Texas Instruments Incorporated | Higher order sigma-delta analog-to-digital converter based on finite impulse response filter |
US7561635B2 (en) * | 2003-08-05 | 2009-07-14 | Stmicroelectronics Nv | Variable coder apparatus for resonant power conversion and method |
GB2440192B (en) * | 2006-07-17 | 2011-05-04 | Ubidyne Inc | Antenna array system |
US7460046B2 (en) * | 2006-12-22 | 2008-12-02 | Infineon Technologies Ag | Sigma-delta modulators |
CN102340314A (zh) * | 2010-07-28 | 2012-02-01 | 中兴通讯股份有限公司 | 一种∑-δ调制器 |
US20120128040A1 (en) | 2010-11-23 | 2012-05-24 | Peter Kenington | Module for an Active Antenna System |
US9231614B2 (en) * | 2014-04-07 | 2016-01-05 | Analog Devices, Inc. | Cancellation of feedback digital-to-analog converter errors in multi-stage delta-sigma analog-to-digital converters |
JP5997803B2 (ja) * | 2015-05-22 | 2016-09-28 | 株式会社日立製作所 | 無線送信機、無線受信機、無線通信システム、昇降機制御システムおよび変電設備制御システム |
US9385746B1 (en) * | 2015-07-28 | 2016-07-05 | Avago Technologies General Ip (Singapore) Pte. Ltd. | Dynamic offset cancellation in sigma-delta converter |
US9742426B2 (en) * | 2015-12-15 | 2017-08-22 | Analog Devices, Inc. | Signal transfer function equalization in multi-stage delta-sigma analog-to-digital converters |
US9838031B2 (en) | 2015-12-16 | 2017-12-05 | Analog Devices Global | Dither injection for continuous-time MASH ADCS |
US9768793B2 (en) * | 2015-12-17 | 2017-09-19 | Analog Devices Global | Adaptive digital quantization noise cancellation filters for mash ADCs |
US9503120B1 (en) | 2016-02-29 | 2016-11-22 | Analog Devices Global | Signal dependent subtractive dithering |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5648779A (en) * | 1994-12-09 | 1997-07-15 | Advanced Micro Devices, Inc. | Sigma-delta modulator having reduced delay from input to output |
Family Cites Families (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100219021B1 (ko) * | 1990-04-06 | 1999-09-01 | 제이 엘. 차스킨, 버나드 스나이더, 아더엠. 킹 | 성분 감도가 낮은 오버샘플된 3차 시그마 델타 아날로그-디지탈 변환기 네트워크 |
NL9001441A (nl) * | 1990-06-22 | 1992-01-16 | Philips Nv | Sigma-delta modulator. |
US5225787A (en) * | 1991-05-10 | 1993-07-06 | U.S. Philips Corporation | Sampling frequency converter including a sigma-delta modulator |
US5144308A (en) * | 1991-05-21 | 1992-09-01 | At&T Bell Laboratories | Idle channel tone and periodic noise suppression for sigma-delta modulators using high-level dither |
US5392040A (en) * | 1992-02-24 | 1995-02-21 | Sanyo Electric Co., Ltd. | Bit compression circuit used for a delta sigma type digital-to-analog converter |
DE4208232A1 (de) * | 1992-03-14 | 1993-09-16 | Siegbert Prof Dr Ing Hentschke | Kompensierender digital-analog-wandler mit aufloesungserhoehender rauschfilterung |
JPH05284033A (ja) * | 1992-03-31 | 1993-10-29 | Yokogawa Electric Corp | Σδ変調器 |
US5274375A (en) * | 1992-04-17 | 1993-12-28 | Crystal Semiconductor Corporation | Delta-sigma modulator for an analog-to-digital converter with low thermal noise performance |
US5414424A (en) * | 1993-08-26 | 1995-05-09 | Advanced Micro Devices, Inc. | Fourth-order cascaded sigma-delta modulator |
JP3367800B2 (ja) * | 1994-09-30 | 2003-01-20 | 株式会社東芝 | 選択装置およびこれを用いたa/d変換器並びにd/a変換器 |
US5760722A (en) * | 1995-01-31 | 1998-06-02 | The United States Of America As Represented By The Secretary Of The Navy | Distributed quantization noise transmission zeros in cascaded sigma-delta modulators |
KR100189525B1 (ko) * | 1995-08-08 | 1999-06-01 | 윤종용 | 시그마 델타 변조방식의 디지탈/아나로그 변환장치 |
DE19722434C1 (de) * | 1997-05-28 | 1998-10-01 | Siemens Ag | Vorrichtung zur Digital-Analog-Wandlung mit hoher Linearität |
JP4209035B2 (ja) * | 1999-05-28 | 2009-01-14 | 株式会社ルネサステクノロジ | Δςモジュレータ、daコンバータ、および、adコンバータ |
-
1999
- 1999-08-06 DE DE19937246A patent/DE19937246B4/de not_active Expired - Fee Related
-
2000
- 2000-08-03 WO PCT/DE2000/002604 patent/WO2001011785A2/de active Application Filing
- 2000-08-03 US US09/806,927 patent/US6518904B1/en not_active Expired - Lifetime
- 2000-08-03 JP JP2001515542A patent/JP2004500745A/ja active Pending
- 2000-08-03 CN CNB008021155A patent/CN1135706C/zh not_active Expired - Fee Related
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5648779A (en) * | 1994-12-09 | 1997-07-15 | Advanced Micro Devices, Inc. | Sigma-delta modulator having reduced delay from input to output |
Non-Patent Citations (2)
Title |
---|
DUNN C ET AL: "EFFICIENT LINEARISATION OF SIGMA-DELTA MODULATORS USING SINGLE-BIT DITHER" ELECTRONICS LETTERS,GB,IEE STEVENAGE, Bd. 31, Nr. 12, 8. Juni 1995 (1995-06-08), Seiten 941-942, XP000528826 ISSN: 0013-5194 * |
FISCHER G ET AL: "ALTERNATIVE TOPOLOGIES FOR SIGMA-DELTA MODULATORS - A COMPARATIVE STUDY" IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II: ANALOG AND DIGITAL SIGNAL PROCESSING,US,IEEE INC. NEW YORK, Bd. 44, Nr. 10, 1. Oktober 1997 (1997-10-01), Seiten 789-797, XP000738779 ISSN: 1057-7130 * |
Also Published As
Publication number | Publication date |
---|---|
CN1135706C (zh) | 2004-01-21 |
DE19937246B4 (de) | 2005-12-22 |
WO2001011785A3 (de) | 2001-09-27 |
JP2004500745A (ja) | 2004-01-08 |
CN1338152A (zh) | 2002-02-27 |
US6518904B1 (en) | 2003-02-11 |
DE19937246A1 (de) | 2001-03-22 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
DE19937246B4 (de) | Kaskadierter Sigma-Delta-Modulator | |
EP1224739B1 (de) | Sigma-delta-modulator | |
DE4311259C2 (de) | Analog/Digital-Wandler mit Kalibrierung und Verfahren zur Ausführung einer Analog/Digital-Wandlung | |
DE60007087T2 (de) | Verfahren und gerät zur korrektur von delta-sigma-wandlern hoher ordnung | |
DE3021012A1 (de) | Verallgemeinertes interpolativers verfahren zur digital-analog-umsetzung von pcm signalen | |
DE4237875C2 (de) | Delta-Sigma-Konverter n-ter Ordnung und Verfahren zur Delta-Sigma-Konvertierung | |
DE3047447C2 (de) | Digitaler Verstärker zum bedarfsweisen Erweitern bzw. Einengen des Dynamikbereiches eines an den Verstärker gelegten digitalen Eingangssignals | |
DE60212440T2 (de) | Bandpass-sigma-delta-modulator mit antiresonanzaufhebung | |
DE2638534A1 (de) | Codierer zum umwandeln eines analogen eingangssignals in ein digitales ausgangssignal | |
DE4127078A1 (de) | Phasenentzerrer fuer einen digital/analog-wandler | |
EP1001538A2 (de) | Sigma-Delta-Modulator und Verfahren zur Unterdrückung eines Quantisierungsfehlers in einem Sigma-Delta-Modulator | |
DE19521609B4 (de) | Dezimationsfilter mit wählbarem Dezimationsverhältnis und Verfahren zur Dezimationsfilterung | |
DE69923259T2 (de) | Digitaler Filter | |
DE10153309B4 (de) | Digital-Analog-Umsetzer-Vorrichtung mit hoher Auflösung | |
DE19722434C1 (de) | Vorrichtung zur Digital-Analog-Wandlung mit hoher Linearität | |
DE69434276T2 (de) | Datenwandler mit Skalierung der Verstärkung zusammen mit einem Zittersignal | |
WO2000035096A2 (de) | Analog-digital-umsetzer | |
DE19521610B4 (de) | Dezimationsfilter unter Verwendung einer Nullfüllschaltung zur Lieferung eines wählbaren Dezimationsverhältnisses sowie Verfahren zur Dezimationsfilterung | |
WO2006024317A1 (de) | Sigma-delta-analog-digital-wandler für eine xdsl-multistandard-eingangsstufe | |
DE102008064744B3 (de) | Empfängeranordnung | |
EP1184783B1 (de) | Verlustleistungsarme Addierer- und Saturierungsschaltung | |
EP1456955B1 (de) | Breitbandiger sigma-delta modulator | |
EP1129523A1 (de) | Schaltungsanordnung zur quantisierung digitaler signale und filterung des quantisierungsrauschens | |
EP1048112A2 (de) | Sigma-delta-d/a-wandler | |
WO2002061950A2 (de) | Sigma-delta-modulator zur digitalisierung von analogen hochfrequenzsignalen |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 00802115.5 Country of ref document: CN |
|
AK | Designated states |
Kind code of ref document: A2 Designated state(s): CN JP US |
|
AL | Designated countries for regional patents |
Kind code of ref document: A2 Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE |
|
ENP | Entry into the national phase |
Ref document number: 2001 515542 Country of ref document: JP Kind code of ref document: A |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
WWE | Wipo information: entry into national phase |
Ref document number: 09806927 Country of ref document: US |
|
AK | Designated states |
Kind code of ref document: A3 Designated state(s): CN JP US |
|
AL | Designated countries for regional patents |
Kind code of ref document: A3 Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE |
|
122 | Ep: pct application non-entry in european phase |