TW527768B

TW527768B - Polyphase filter

Info

Publication number: TW527768B
Application number: TW91105801A
Authority: TW
Inventors: Chung-Chiang Ku; Jen-Chiou Bo
Original assignee: Mediatek Inc
Priority date: 2002-03-22
Filing date: 2002-03-22
Publication date: 2003-04-11

Abstract

A polyphase filter is disclosed. The polyphase filter comprises two differential units for receiving complex input signals Xr and Xi to generate complex output signals Yr and Yi, respectively. Each differential unit includes a plurality of differential components. The polyphase filter employees a plurality of feedback units to feedback the complex output signals Yr and Yi to the input terminals and the intermediate points of the differential units. Since the coefficients of the differential units and the feedback units are calculated by shifting the frequency on a real low pass filter, the feedback units can be implemented by resisters and capacitors flexibly.

Description

527768527768

五、發明說明（1) [發明之技術領域] 本發明係關於多相濾波器電路，特別是關於利用頻率偏移並簡化高階低通濾波器而實施之多相濾波器電路 [習知技術] 在高性能之低中頻（low Intermediate-Frequency， low- IF)無線接收器中，鏡射頻帶（image)可由多相淚波器 (poly-phase filter)來濾除。美國第3, 559, 042 號專利「多相對稱式網路（poly phase symmetrical network) 提出一種被動式（passive)電阻電容網路來濾除鏡射頻帶。圖1所示為該被動式電阻電容網路之一個例子。如今圖所示，該電阻電容網路接收多相位輸入訊號v丨、〗v j : -VI、- jVl，並輸出多相位輸出訊號V2、jV2、-V2、 _jV2。因為該網路由電阻與電容等被動元件所構成，雖然可濾除鏡射頻帶’但同時會對訊號造成衰減，例如會衰 6db的功率。因此，在使用該濾波電路時，必須在後加放大器，使成本提高且電路複雜。曰另外，A.S. Sedra 在 1 985 IEEE 期刊，ISCAS 第 1 223- 1 226頁中提出一種主動式（active)多相位濾波器。該濾波器將實數（real)之低通濾波器（1〇w pass fUte〇作頻率線性位移而形成複數帶通濾波器（c〇mplex band pass filter)。圖2為該主動式多相位濾波器之架構圖。如該圖所示，輸入訊號义（幻經過一轉移函數（Transfer funCti〇n)T(s)後，形成輸出訊號Y(s)。轉移函數T(s)、V. Description of the Invention (1) [Technical Field of the Invention] The present invention relates to a polyphase filter circuit, and more particularly to a polyphase filter circuit implemented using a frequency offset and simplifying a high-order low-pass filter. [Known Technology] In a high-performance low-intermediate-frequency (low-IF) wireless receiver, the mirror radio frequency band (image) can be filtered by a poly-phase filter. U.S. Patent No. 3,559,042 "poly phase symmetrical network proposes a passive resistor-capacitor network to filter the RF band of the mirror. Figure 1 shows this passive resistor-capacitor network An example. As shown in the figure, the resistor-capacitor network receives multi-phase input signals v 丨, 〖vj: -VI,-jVl, and outputs multi-phase output signals V2, jV2, -V2, _jV2. Because the network routing It is composed of passive components such as resistors and capacitors. Although it can filter the RF band of the mirror, it will attenuate the signal at the same time, for example, it will attenuate 6dB of power. Therefore, when using this filter circuit, an amplifier must be added after the filter to increase the cost. And the circuit is complicated. In addition, AS Sedra proposed an active polyphase filter in 1 985 IEEE Journal, ISCAS pages 1 223-1 226. This filter is a real low-pass filter ( 10w pass fUte〇 linear frequency shift to form a complex band-pass filter (complex band pass filter). Figure 2 is the architecture diagram of the active polyphase filter. As shown in the figure, the input signal (Magic via a rear transfer function (Transfer funCti〇n) T (s), to form an output signal Y (s). The transfer function T (s),

第5頁 527768 五、發明說明（2) 分別如式輸入訊號X(S)與輸出訊缺v ⑴、式⑺與式（3)V^Y(^為複數型式 T(s)=TR(s)+jTl(s) X(s) =XR(S) +jXj(s) ·.··0) Y(s)=T(s)^X(s) ….(2) =yr(0 + j'Y^s) ….(3) 示，該複數帶通濾波哭Μ 愿及裔之貫施例。如圖3所器31、電阻R與電容‘成轉：波器，其利用QP放大為轉移函數T〗（S)來執人Τ ·多Μ數7“3)，且利用電阻R作個一階之複數帶通濾波口同相位之訊號。雖然可串聯兩方式僅能用電阻來；合；：成二階濾波，。•是，此種大，且必須一階一階；接σ目位之訊號’實施上限制較 [發明概要] 且實組微接輸元，號U 數個一端有繁於上述問題，太 =有彈性的多相“器ΐ:的是提出—種易於實施分單in:·本發明多相濾波器電路包含入訊號Xr，而；之複數個微分項，輪入端；係包含串l輸出為輸出訊號卜；第m八連 =接連接之複數個微分 ::放分單 :輸㈣為輪出訊號Yl ; 一回授=連接輪入訊連接至第-組以均連接至輸出訊號hΖ 支刀早凡之各串接微分項的輪入端而; ^//68 五、發明說明⑶ -------- 〜回授單元，係包含_ 敌大器之輸入端連接向放大器與複數個電阻，該反向端連接至各電阻之輪出訊號以，而反向放大器之輸出分單元之各串接微分=各電阻之輸出端連接至第一組微複數個電阻，每個電阻的，入端；第三回授單元，係包含另一端連接至第二組二=f 7端均連接至輸出訊號Yi，而以及第四回授單元，=單元之各串接微分項的輸入端；端均連接至輸出訊含複，=電•，每個電阻之第-之各串接微分項的^入端而另一端連接至第二組微分單元單元!=:各=3=:容取代，並回授到微分 =率偏移後求的，且回授麵合時器經，阻、電容或兩者來實施…“施階 [實施例] 以下參考圖式詳細說明本發明多相濾波器電路。一般二階的低通濾波器之轉移函數經過拉普杈 CLaplace Transformation)後，其通式如式（4)所示·欠換聊= .肩其中，當= 時為實數Butterworth低通濾波 (LPF)。若將式（4)的頻域偏移一個量，即\ ^Page 5 527768 V. Description of the invention (2) The input signal X (S) and the output signal lack v ⑴, formula ⑺ and formula (3) V ^ Y (^ is a complex type T (s) = TR (s) ) + jTl (s) X (s) = XR (S) + jXj (s) ··· 0) Y (s) = T (s) ^ X (s)…. (2) = yr (0 + j'Y ^ s)…. (3) shows that the complex band-pass filtering method is consistent with the embodiment. As shown in Fig. 3, the resistor R and the capacitor are converted: a wave filter, which uses QP to amplify the transfer function T (S) to perform the T · M number 7 "3), and uses the resistor R to make a one The order of the complex bandpass filter port is the same phase signal. Although the two methods can be connected in series, only the resistor can be used; combined ;: a second-order filter. • Yes, this type is large, and must be first-order first-order; The implementation of the signal is more limited than the [Summary of the Invention], and the real group is micro-connected to the input element. There are several ends of the signal U that are complicated by the above problems. Too = flexible multi-phase. : · The polyphase filter circuit of the present invention includes an input signal Xr, and; a plurality of differential terms, a round-in terminal; includes a string l output as an output signal; the eighth connection = a plurality of differentials connected :: put Ordering: the input is the round signal Yl; one feedback = connected to the round-in signal connected to the-group to be connected to the round-in end of each of the serial differential items of the output signal hZ branch knife; ^ // 68 V. Description of the invention ⑶ -------- ~ The feedback unit contains the input terminal of the _ enemy device connected to the amplifier and a plurality of resistors, the reverse Connected to the output signal of each resistor, and the series differential of the output subunit of the inverting amplifier = the output terminal of each resistor is connected to the first group of micro-complex resistors, each of which is the input terminal; The feedback unit includes the other end connected to the second group of two = f 7 terminals are connected to the output signal Yi, and the fourth feedback unit, = the input terminal of each serial derivative of the unit; the terminals are connected to the output signal Containing complex, = electricity •, the-of each resistor is connected in series with the ^ input end of the differential term and the other end is connected to the second set of differential unit units! =: Each = 3 =: capacity replacement, and feedback to the differential = Calculated after the rate offset, and implemented by feedback loops, resistors, capacitors, or both ... "Ordering [Example] The following describes the polyphase filter circuit of the present invention in detail with reference to the drawings. General second-order After the transfer function of the low-pass filter has undergone the Laplacian transformation (CLaplace Transformation), its general formula is as shown in formula (4): Under-replacement =. Where, when = is a real Butterworth low-pass filter (LPF). An offset in the frequency domain of equation (4), that is, \ ^

第7頁 527768 五、發明說明（4)Page 7 527768 V. Description of the invention (4)

。則式（4 )變成：哪-碑—义)+1 __1_ -..(5) …(6) …C7). Then the formula (4) becomes: which- tablet-right) +1 __1_-.. (5)… (6)… C7)

"S2 i-aS + \+S\-{a + 2S)S?i —雨 _Zl±ZL 总+成因此，從式（5 )可求的 Χγ =7,[(^2 + c^ + (^2m +1)))+2¾^ 4 = g [ (f + W + (此 +1))] Κ7χ) 其中，s\={j〇}y = -ω\ 。根據式（6)與式（7)，若將Yr 與Yi移到左邊，可變換成式（8)與式（9): 根據式（8)與式（9)，Yr與Yi分別包含5個項目，Yr包 1 π、 av , S\+\v ^ 2ωΆ ν αωκ ν 含斤一一~^~ r 一了 ^ 與一^^ ，而Yi包含 v、S 、 ^2«+lv 2¾ v 咖ητ7 丄 y 其中，可以 S2 s 與 s" S2 i-aS + \ + S \-{a + 2S) S? i —Rain_Zl ± ZL total + result. Therefore, from the formula (5), χγ = 7, [(^ 2 + c ^ + (^ 2m +1))) + 2¾ ^ 4 = g [(f + W + (this +1))] Κ7χ) where s \ = {j〇} y = -ω \. According to equations (6) and (7), if Yr and Yi are moved to the left, they can be transformed into equations (8) and (9): According to equations (8) and (9), Yr and Yi respectively contain 5 Items, Yr package 1 π, av, S \ + \ v ^ 2ωΆ ν αωκ ν contains jin ~~~~ r one ^ and one ^^, and Yi contains v, S, ^ 2 «+ lv 2¾ v Coffee ητ7 丄 y where S2 s and s

第一微分單元來實施、P 可以第二微分單元來實施First differential unit to implement, P can be implemented to second differential unit

¥Xr' 〜s2«+lv 2〇}及 ν (Χωη ν s r s2 r S、S2 1 …⑻ 丄JT - S2 1 a S H +1 2¾ ， s 2 s2 2 S s2 r …(9) 第8頁 527768 五、發明說明（5) ^ A +1 s2 y可以第 2ωΜ 回授單元來實施、s 可以第二回授單元來實施〜 ^+1 2%與與 S i輿一 $可以第三回授單元來實施、以及 κ 丄— ^ ^〜可以第四回授單構根據式(8) #式⑼，即可設計出如圖4 圖4所示為本發明多相遽波器之第—實施例的架構圖。如該圖所7 ’輸人信號包含實數與虛數以部分，輸出信號亦包含實數Yr與虛數Yi兩部分。由於回授單元可回授到不同位置，目此回授單元之元件可以電阻或電容實施。圖4中係利用加法器將回授單元所回授的信號加入迴路信號。圖5所示為圖4架構圖之電路，該電路中的回授單元之元件均以電阻貫施。如圖5所示，式（5)之1/s項（第一微分單元）是由0P放大器41、42與一電容Cl、C2所構成、Yr之負回授（第一回授單元）是由電阻以、R2來耦合、而Yi之正回技（苐、一回授單元）是由電阻R3、R4與反向放大器45來|馬合。而式（6)之Ι/s項（第二微分單元）是由〇p放大器43、44 與一電容C3、C4所構成、Yi之負回授（第三回授單元）是由電阻R 5、R6來耦合、而“之負回授（第四回授單元）是由電阻R7、R8來耦合。式（8)與式（9)還可變換成式（1〇)與式（11):¥ Xr '~ s2 «+ lv 2〇} and ν (χωη ν sr s2 r S, S2 1… ⑻ TJT-S2 1 a SH +1 2¾, s 2 s2 2 S s2 r… (9) page 8 527768 V. Description of the invention (5) ^ A +1 s2 y can be implemented by the second ωΜ feedback unit, s can be implemented by the second feedback unit ~ ^ + 1 2% and a third feedback can be made with S i The unit can be implemented, and κ 丄 — ^ ^ ~ The fourth feedback single structure can be designed according to formula (8) # Formula ⑼, and the design of the multi-phase wave wave generator of the present invention can be designed as shown in FIG. 4 and FIG. 4. The architecture diagram of the example. As shown in the figure, the input signal contains real and imaginary numbers, and the output signal also contains two parts: real number Yr and imaginary number Yi. Since the feedback unit can feedback to different locations, the feedback unit The components can be implemented by resistors or capacitors. In Figure 4, the signal returned by the feedback unit is added to the loop signal by using an adder. Figure 5 shows the circuit of the architecture diagram of Figure 4, and the components of the feedback unit in the circuit are all based on Resistance is applied. As shown in Fig. 5, the 1 / s term (the first differential unit) of equation (5) is composed of 0P amplifiers 41, 42 and a capacitor Cl, C2, and the negative return of Yr (The first feedback unit) is coupled by resistors R2, and Yi's positive feedback technique (苐, a feedback unit) is by resistors R3, R4 and the inverting amplifier 45 | Mahe. (6 The 1 / s term (second differential unit) is composed of oop amplifiers 43, 44 and a capacitor C3, C4, and the negative feedback of Yi (third feedback unit) is coupled by resistors R 5, R6 The negative feedback (the fourth feedback unit) is coupled by resistors R7 and R8. Equations (8) and (9) can also be transformed into equations (10) and (11):

第9頁 527768 五、發明說明（6) …(1。） γ「-..01) 式（1 〇 )、（ 11)與式（8 )、（ 9 )之差異是將一部份的回授項目合併。因此，根據式（1 〇 )、（ 1 1)即可設計出如圖6之電路架構。圖7所示為圖6架構圖之電路，該電路中的回授單元之元件以電阻與電容實施。如圖7所示，式（1〇)之i/s 項（第一微分單元）是由0P放大器41、42與一電容Cl、C2所構成、Yr之負回授（第一回授單元）是由電阻R1、r2來耦合、而Yi之正回授（第二回授單元）是由電阻R9、電容C5與反向放大态45來搞合。而式（11)之i/s項（第一微分單元）是由0P放大器43、44與一電容C3、C4所構成、Yi之負回授 (第三回授單元）是由電阻R5、R6來耦合、而Yr之負回授 (第四回授單元）是由電阻Rl〇、C6來耦合。、當然’亦可將式（10)右邊之兩個Yr項的係數合併，同時將式（1 1)右邊之兩個Y i項的係數合併。如此，圖7之^ 負回授可由電阻與電容來耦合，同時^之負回授亦可由% 阻與電容來耦合。斯變換後以下敘述為四階多相濾波器電路之實施例。另外，其他高階多相濾波器電路之實施例亦可參照此四階之實施八例。四階的低通濾波器之轉移函數經過拉普妆白 ^ 其通式如式（Α1)所示：Page 9 527768 V. Explanation of the invention (6)… (1.) γ "-.. 01) The difference between formulas (10) and (11) and formulas (8) and (9) is to return a part of Therefore, the circuit structure shown in Fig. 6 can be designed according to equations (10) and (1 1). Fig. 7 shows the circuit of the structure diagram of Fig. 6. The components of the feedback unit in this circuit are The resistor and capacitor are implemented. As shown in Figure 7, the i / s term (the first differential unit) of equation (10) is composed of OP amplifiers 41 and 42 and a capacitor Cl and C2, and the negative feedback of Yr (No. A feedback unit) is coupled by resistors R1 and r2, while the positive feedback of Yi (the second feedback unit) is combined by resistor R9, capacitor C5, and the reverse amplification state 45. Whereas (11) The i / s term (the first differential unit) is composed of 0P amplifiers 43, 44 and a capacitor C3, C4. The negative feedback of Yi (the third feedback unit) is coupled by the resistors R5 and R6, and the Yr The negative feedback (the fourth feedback unit) is coupled by the resistors R10 and C6. Of course, the coefficients of the two Yr terms on the right side of equation (10) can also be combined, and the two on the right side of equation (1 1) can be combined. Coefficients of Yi terms, such as Therefore, the negative feedback of FIG. 7 can be coupled by a resistor and a capacitor, and the negative feedback of ^ can also be coupled by a% resistance and a capacitor. The following description is an example of a fourth-order polyphase filter circuit after the Sri Lankan transformation. In addition, Other examples of high-order polyphase filter circuits can also refer to this fourth-order implementation of eight examples. The transfer function of the fourth-order low-pass filter has passed through the Laplace makeup ^ Its general formula is shown in formula (Α1):

第10頁 527768Page 10 527768

、發明說明（7) _1______ +^1 - ^3 +^2 · (A1)Description of the invention (7) _1______ + ^ 1-^ 3 + ^ 2 · (A1)

—S+^+i). (FT^7TJ _ 式(/丨）是將四階的函式拆成兩個二階函數相乘，亦即則項與後項。若將式（A1)的頻域偏移一個量，即則式（A1)變成式（A2)—S + ^ + i). (FT ^ 7TJ _ Formula (/ 丨) is a multiplication of the fourth-order function into two second-order functions, that is, the term and the latter term. If the frequency domain of the formula (A1) By an amount, the formula (A1) becomes the formula (A2)

(亦即 > —X (A2) ^+^ + 1 + ^-(^+2^ Y2 + 深 + \ + S\ - [β + 23]3及，n〇s) r2〇g) ^ri(S)' X2(S) —+^2 xr2+jxi2 因此，從式（A2)可求的 = ^ri[(^2 +^+(^2» + ΐ))]+2ωκ^1 …(A3) ^ίΐ =^ii[(^2 +〇ώ? + (^2Μ +1)))-(2^^7^ +αωκΥγ])…(Α4) ^2=^2 +/^+{s\ +1))1+2¾¾ +βωηΥί2 ...(Α3.1) = ^[(^2 +^ + (^+ΐ))]-(2^2 +βωηΥγ2) ...(Α4.1) 其中，SKjmJ: 一ω\ ，且前項之輸出信號Yr 1、Yi 1 作為後項之輸入信號Xr2、Xi2。所以，根據式（A3)、 (A4)、（Α3.1)、（Α4·1)可轉換成式（A5)、（A6)、（A5.1)(I.e. --X (A2) ^ + ^ + 1 + ^-(^ + 2 ^ Y2 + depth + \ + S \-[β + 23] 3 and, n〇s) r2〇g) ^ ri (S) 'X2 (S) — + ^ 2 xr2 + jxi2 Therefore, what can be obtained from the formula (A2) = ^ ri [(^ 2 + ^ + (^ 2 »+ ΐ))] + 2ωκ ^ 1… ( A3) ^ ίΐ = ^ ii [(^ 2 + 〇ώ? + (^ 2Μ +1)))-(2 ^^ 7 ^ + αωκΥγ]) ... (Α4) ^ 2 = ^ 2 + / ^ + {s \ +1)) 1 + 2¾¾ + βωηΥί2 ... (Α3.1) = ^ [(^ 2 + ^ + (^ + ΐ))]-(2 ^ 2 + βωηΥγ2) ... (Α4.1) Among them, SKjmJ: -ω \, and the output signals Yr 1, Yi 1 of the preceding item are used as the input signals Xr2, Xi2 of the latter item. Therefore, according to formulas (A3), (A4), (Α3.1), (Α4 · 1), it can be converted into formulas (A5), (A6), (A5.1)

第11頁 527768 五、發明說明（8) (A6.1)： -f ^^...(A5) ^ - f 4 - +争4 +安心 …· (A6) ^ t - ft - -争匕-令匕 ·.. (A5.1) -(A6.1) 如上所述，四階多相濾波器可由式（A 5 )、（ A 6 )、（ A 5 ·Page 11 527768 V. Description of the invention (8) (A6.1): -f ^^ ... (A5) ^-f 4-+ contend 4 + peace of mind ... (A6) ^ t-ft--contend for dagger -Let .. (A5.1)-(A6.1) As mentioned above, the fourth-order polyphase filter can be expressed by equations (A 5), (A 6), (A 5 ·

1)、（ A 6 · 1)所表示，亦即四階多相遽波器可由兩個串接之二階多相濾波器實施。圖8所示為本發明四階多相濾波器之架構圖。如該圖所示，四階多相濾波器包含兩個串接之二階多相濾波器8 1、82，二階多相濾波器8 1接收包含實數 Xr與虛數Xi之輸入信號，且將輸出信號輸入至二階多相濾波器8 2。二階多相濾波器8 2則產生包含實數Yr與虛數Y i之輸出信號。該等二階多相濾波器8 1、8 2之參數α與/5可以設計成不同之數值。由於二階多相濾波器8 1、8 2與上述之第一實施例之二階多相濾波器相同，不再重複說明。1), (A 6 · 1), that is, the fourth-order polyphase chirp wave filter can be implemented by two second-order polyphase filters connected in series. FIG. 8 is a structural diagram of a fourth-order polyphase filter according to the present invention. As shown in the figure, the fourth-order polyphase filter includes two serially connected second-order polyphase filters 8 1, 82, and the second-order polyphase filter 8 1 receives an input signal including a real number Xr and an imaginary number Xi, and outputs an output signal. Input to second-order polyphase filter 8 2. The second-order polyphase filter 8 2 generates an output signal including a real number Yr and an imaginary number Yi. The parameters α and / 5 of the second-order polyphase filters 8 1 and 8 2 can be designed to different values. Since the second-order polyphase filters 8 1 and 8 2 are the same as the second-order polyphase filter of the first embodiment described above, the description will not be repeated.

圖9所示為本發明四階多相濾波器之另一實施例的架構圖。如該圖所示，四階多相濾波器包含兩個串接之二階多相濾波器9 1、92，二階多相濾波器9 1接收包含實數Xr與虛數X i之輸入信號，且將輸出信號輸入至二階多相濾波器 9 2。二階多相濾波器9 2則產生包含實數Y r與虛數Y i之輸出信號。該等二階多相濾波器9 1、9 2之參數α與/3可以設計Fig. 9 is a block diagram showing another embodiment of a fourth-order polyphase filter according to the present invention. As shown in the figure, the fourth-order polyphase filter includes two serially connected second-order polyphase filters 9 1, 92, and the second-order polyphase filter 9 1 receives an input signal including a real number Xr and an imaginary number X i and outputs The signal is input to a second-order polyphase filter 9 2. The second-order polyphase filter 92 generates an output signal including a real number Y r and an imaginary number Y i. The parameters α and / 3 of the second-order polyphase filters 9 1 and 9 2 can be designed.

第12頁 527768 五、發明說明（9) 成不同之數值。由於二階多相濾波器9 1、9 2與上述之第二實施例之二階多相濾波器相同，不再重複說明。由於本發明直接將高階（例如2階、3階、…）之實數低通濾波器經過頻率偏移後，產生多相位帶通濾波器。因此，可直接從高階轉移函數合成，不須對每一階進行I /Q 耦合。同時，回授耦合時僅在需要回授耦合之階數由電阻、電容或兩者來實施耦合。Page 12 527768 V. Description of the invention (9) Different values. Since the second-order polyphase filters 9 1 and 92 are the same as the second-order polyphase filters of the second embodiment described above, the description will not be repeated. Because the present invention directly performs a high frequency (for example, 2nd, 3rd, ...) real number low-pass filter after frequency offset, a polyphase bandpass filter is generated. Therefore, it can be synthesized directly from higher-order transfer functions without the need for I / Q coupling for each order. At the same time, the feedback coupling is performed by resistor, capacitor or both only when the order of feedback coupling is needed.

以上雖以實施例說明本發明，但並不因此限定本發明之範圍，只要不脫離本發明之要旨，該行業者可進行各種變形或變更。Although the present invention has been described by way of examples, the scope of the present invention is not limited thereby, and those skilled in the art can make various modifications or changes without departing from the gist of the present invention.

第13頁 527768 圖式簡單說明【圖式之簡要說明】圖1為被動式電阻電容網路之濾波器。圖2為主動式多相位濾波器之架構圖。圖3所示為圖2複數帶通濾波器之實施例。圖4所示為本發明二階多相濾波器之第一實施例的架構圖。圖5所示為圖4架構圖之實施電路。圖6所示為本發明二階多相濾波器之第二實施例的架構圖。Page 13 527768 Brief description of the diagram [Brief description of the diagram] Fig. 1 is a filter of a passive resistor-capacitor network. FIG. 2 is a structural diagram of an active polyphase filter. FIG. 3 shows an embodiment of the complex band-pass filter of FIG. 2. Fig. 4 is a block diagram showing a first embodiment of a second-order polyphase filter according to the present invention. FIG. 5 shows an implementation circuit of the architecture diagram of FIG. 4. Fig. 6 is a block diagram showing a second embodiment of the second-order polyphase filter of the present invention.

圖7所示為圖4架構圖之實施電路。圖8所示為本發明四階多相濾波器之第一實施例的架構圖。圖9所示為本發明四階多相濾波器之第二實施例的架構圖。【圖式編號】 41、42、43、44 0P 放大器 45 反向放大器FIG. 7 shows an implementation circuit of the architecture diagram of FIG. 4. Fig. 8 is a block diagram showing a first embodiment of a fourth-order polyphase filter according to the present invention. Fig. 9 is a block diagram showing a second embodiment of a fourth-order polyphase filter according to the present invention. [Pattern number] 41, 42, 43, 44 0P amplifier 45 Inverting amplifier

81、82、91、92 二階多相濾波器81, 82, 91, 92 second-order polyphase filters

第14頁Page 14

Claims

527768 六、申請專利範圍 1 · 一種多相濾波器電路，出預設頻帶範圍之輸出訊號yr盥Yi j入訊號計與h，輪含·· /、垓多相濾波器電路包第一組微分單元，係包含串接輪入端連接前述輸入訊號Xr，而輪禝數個微分項，第二組微分單元，係、包含串^輸出訊號h ; 輸入端連接前述輸入訊號Xi，而輸 2數個微分項，第-回授單元，係包含複數個電：為，出訊號η ; 端均連接至前述輸出訊號Yr 鱼母個電阻之第— 微分單元之各串接微分項的輸入端；-連接至前述第—組第二回授單元，係包含一反該反向放大器之輸入端連接至前述輪出=复數個電随，大器之輸出端連接至各電阻之一端，，而反向放至前，一組，分單元之各串接微分項：：：：出端連接山第二回授單70，係包含複數個電阻，每個電阻端均連接至前述輸出訊號Yi，而另一端、=第一微分單元之各串接微分項的輸入端；以及别述第二組第四回授單元，係包含複數個電阻，端均連接至前述輸出訊號Yr，而另一端之第一微分單元之各串接微分項的輸入端。則第二組 2?申請專利範圍第i項所記載之多相渡波其中則述第一組微分單元與第二組微分單元电路，放大器與電容所構成。 A 77項係由 3·如申請專利範圍第2項所記載之多相濾波器電路，第15頁 527768 六、申請專利範圍第四回授單元，係由電阻與電容所構成，每個電阻與電容之第一端均連接至前述輸出訊號Yr，而另一端連接至前述第二組微分單元之部分微分項的輸入端。 6. 如申請專利範圍第5項所記載之多相濾波器電路，其中前述第一組微分單元與第二組微分單元之微分項係由放大器與電容所構成。 7. 如申請專利範圍第6項所記載之多相濾波器電路，其中該多相濾波器電路為二階之多相濾波器電路，且前述第一組微分單元與第二組微分單元均包含兩個串接之微分項。 8. 如申請專利範圍第7項所記載之多相濾波器電路，其中前述第一回授單元包含一電阻與一電容，且該電阻與電容的另一端連接至第一組微分單元之輸入端。 9. 如申請專利範圍第7項所記載之多相濾波器電路，其中前述第二回授單元包含一電阻與一電容，且該電阻與電容的另一端連接至第一組微分單元之輸入端。 1 0.如申請專利範圍第7項所記載之多相濾波器電路，其中前述第三回授單元包含一電阻與一電容，且該電阻與電容的另一端連接至第二組微分單元之輸入端。 11.如申請專利範圍第7項所記載之多相濾波器電路，其中前述第四回授單元包含一電阻與一電容，且該電阻與電容的另一端連接至第二組微分單元之輸入端。 1 2.如申請專利範圍第7項所記載之多相濾波器電路，其中可串接複數個前述多相濾波器電路，藉以構成更高階527768 VI. Application for patent scope 1 · A polyphase filter circuit, output signal of preset frequency range yr Y Yi j input signal meter and h, wheel containing · / / 垓 polyphase filter circuit package first set of differential The unit includes a serial input terminal connected to the aforementioned input signal Xr, and a plurality of differential terms. The second set of differential units includes a serial output signal h; the input terminal is connected to the aforementioned input signal Xi, and outputs 2 digits. Each differential term, the-feedback unit, includes a plurality of electric power: is, the output signal η; the terminals are connected to the aforementioned output signal Yr, the first resistor of the resistor unit in series-the input terminal of the differential term;- It is connected to the second feedback unit of the first group, which includes an input terminal of the inverting amplifier connected to the aforementioned round-out = a plurality of electrical relays, the output terminal of the amplifier is connected to one of the resistors, and the Put to the front, one set, each series of sub-differentials of the sub-unit :::: The second terminal is connected to the second feedback order 70, which contains a plurality of resistors, each of which is connected to the aforementioned output signal Yi, One end, = of the first differential unit The input terminal of the differential term is connected in series; and the second group of the fourth feedback unit, which includes a plurality of resistors, is connected to the output signal Yr, and each of the first differential unit of the other end is connected to the differential term in series. Input. The second group 2? Polyphase wave described in item i of the scope of patent application. Among them, the first group of differential units and the second group of differential units are composed of circuits, amplifiers and capacitors. A 77 item is composed of 3. Polyphase filter circuit as described in item 2 of the scope of patent application, page 15 527768 6. The fourth feedback unit of the scope of patent application is composed of resistors and capacitors, each resistor and The first terminal of the capacitor is connected to the aforementioned output signal Yr, and the other terminal is connected to the input terminal of a part of the differential term of the aforementioned second set of differential units. 6. The polyphase filter circuit described in item 5 of the scope of patent application, wherein the differential term of the first group of differential units and the second group of differential units is composed of an amplifier and a capacitor. 7. The polyphase filter circuit described in item 6 of the scope of patent application, wherein the polyphase filter circuit is a second-order polyphase filter circuit, and the aforementioned first group of differential units and the second group of differential units each include two Differential term in series. 8. The polyphase filter circuit described in item 7 of the scope of patent application, wherein the first feedback unit includes a resistor and a capacitor, and the other end of the resistor and the capacitor is connected to the input terminal of the first group of differential units. . 9. The polyphase filter circuit described in item 7 of the scope of patent application, wherein the second feedback unit includes a resistor and a capacitor, and the other end of the resistor and the capacitor is connected to the input terminal of the first group of differential units. . 10. The polyphase filter circuit described in item 7 of the scope of the patent application, wherein the third feedback unit includes a resistor and a capacitor, and the other end of the resistor and the capacitor is connected to the input of the second group of differential units. end. 11. The polyphase filter circuit described in item 7 of the scope of patent application, wherein the fourth feedback unit includes a resistor and a capacitor, and the other end of the resistor and the capacitor is connected to the input terminal of the second group of differential units. . 1 2. The polyphase filter circuit described in item 7 of the scope of patent application, wherein a plurality of the aforementioned polyphase filter circuits can be connected in series to form a higher order

527768 六、申請專利範圍之多相濾波器電路。 _I_H527768 6. Polyphase filter circuit with patent application scope. _I_H