TW589812B - Frequency offset estimation for communication systems method and device for inter symbol interference - Google Patents

Abstract

A frequency offset estimation based on state-based differential accumulation and the device thereof are disclosed. The concept of the sate-based operation is introduced by mathematical derivations. The knowledge of received data symbols and timing is utilized. Then the detailed operations are also given by both equations and conceptual descriptions. It is unnecessary to estimate the channel jointly or concurrently, while the differential operation over the received samples of the same state is performed. Such operation is obviously much simpler and easier to implement in VLSI than all the other techniques.

Description

V. Description of the invention (1) The technical field to which the invention belongs The invention relates to the field of communication systems, in particular to an architecture for estimating the frequency offset (requency offset), and is applicable to channels having the symbol mterfe (e) channel). Untersymbol's previous technology The universal communication channel for 4 ”wireless communication is often affected by channel defects such as multipath transmission and additional noise. For carrier-modulated systems, = offset is generally caused by the difference between the transmitter and the receiver in this type of system. Le (DQp ㈣ offset and more heart-shaped. The importance of receiving information in the front code _ lies in receiving Wei Lusu's capture frequency and tracking phase,-like silk, large solution offset will produce far more than the receiver's fast phase _ The tracking ability causes serious degradation of the efficiency. Therefore, how to estimate and compensate for the frequency offset in the demodulated W of the receiver is an important task to determine the system performance. At present, many additional white Gaussian noise n. Off, AWGN) frequency offset estimation method developed based on ideal conditions, but in some applications, such as the environment of multiple paths, the distortion of the received signal will cause a considerable degree of intersymbol interference (Referred to as ISI). This phenomenon causes additional noise and reduces the performance of frequency offset estimation, so the ISI problem is particularly difficult in wireless communications. When designing an architecture for estimating frequency offset, it must be solved ISI is problematic, in view of this, according to non-linear operation performed on the received signal, Scott et al punch frequency offset estimation algorithm is one kind, see: ,, Simultane〇us C1〇ck phase and Fre level ㈣y

Offset Estimation ", IEEE Trans, on Commun ·, Vol. 43, ρρ · 2263-2270,

July 1995. This architecture must calculate the Fourier transform and make some approximations based on the impulse response of the channel (impnlseresponse ^ hypothesis. In contrast, Fechte; ^ reveals an algorithm to estimate the frequency offset and obtain the channel, please refer to : ,, Fast Frame 589812 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 B7 V. Invention Description (2)

Synchronization, Frequency Offset Estimation and Channel Acquisition for Spontaneous Transmission over Unknown Frequency-Selective Radio Channels ", Proc · IEEE PIMRC, pp. 229-233, Sep 1993. Based on the maximum-likelihood criterion, Fechtel The method scans the data segments of the received signal to achieve the frequency offset estimation, but the operation of this architecture must be based on an understanding of the received symbols and their timing. In addition, Bahai et al. Show The frequency offset value can be estimated by the phase rotation of the channel coefficients, please refer to: "A Frequency Offset Estimation Technique for Wireless Channels", in 1997 IEEE Workshop on Signal Processing Advances in Wireless Communications 9 Paris' Apr · 1997, pp. 397_4 〇〇. Bahai's algorithm still relies on transmitting known symbol samples. Viswanathan et al. Published a method called maximum state-based accumulation (MSA) estimation method, see: A Frequency

Offset Estimation Technique for Frequency-Selective Fading Channels 55 ^ IEEE Commun. Letters, Vol. 5, pp. 166-168, Apr. 20 (U. However, the operation of this technology must first know the modulation data in the received signal. … Overviewing the conventional ISI channel estimation technology, the disadvantage is that it requires highly complex calculations, which makes it difficult to implement the integrated circuit. SUMMARY OF THE INVENTION The object of the present invention is to provide a frequency offset estimation device suitable for the ISI channel. Since the lion degree of the required operation is low, it is very suitable for applying the integrated circuit. Another object of the present invention is to provide a solution offset estimation architecture that is suitable for ISI communication symbols and its timing. U Received at Jiaowu (please read the precautions on the back before filling in this page) Φ -------- Order W This kind of depolarization miscellaneous meter device, which is turned on the channel of Fuyuan liver disturbance, basin. Bag = storage area , -Difference unit, -power operator, -accumulate n, extract the benefit i and put the material. The storage area has _ units to input in series and receive

This paper Α7 Α7 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. 5. Description of the Invention (3) ----- Sampling phase: rhyme solution element * translation m samples, thus forming a delay 8. Set / '. The sub-unit I makes a difference between the receiving sampling phase and the delayed sampling phase and arrives at the initial value sequence. The power operator receives the preliminary value f =, shoots the number of P filaments, and corrects the preliminary value of the sequential power. Yi input from the transfer accumulator heterologous sequences exponentiation initial value, with respect to the M-sequence reception sampling, between samples, the total rotation of the power take ^ obtained, bonus, and the accumulated value of the plural. The angle is used to obtain the angle of the accumulated value, and the inspection unit further reduces the angle by the proportion of the impulse 'to estimate the frequency offset value of the received sampling sequence. 4 In another aspect, the present invention also discloses a frequency offset estimation device composed of a status indicator, a status library, a difference unit, a weight operator, and a plurality of unique counting terms. Status indicator = Difficult-㈣symbol sequence to generate a status signal representing the status of the symbol. The status of the symbol is defined by a current data symbol and the data symbol received by M recently. length. The state secret has the first end of the input-receiving sampling sequence, the second end of the input target index, and the third end of the above-mentioned status signal. The current index is associated with the data symbol before disk 1. According to the status signal, the status database stores the _current receiving samples of the current data symbols input by the second terminal and the current data symbols input by the-terminal, and = the operation and the current data symbols are the same as the symbol status. Previously received samples and their associated previous months) index, which is expected to be a positive integer. The difference unit performs a differential operation on the M currently received samples in the received sampling sequence, and the difficulty of obtaining the same symbol state. The difference unit is used to obtain a preliminary value sequence. , &Amp; According to the index difference between the current index associated with the above M current receiving samples and the previous index associated with the aforementioned M first receiving samples of the same symbol, each calculation order 4 is indexed by Ke input. Sequence of preliminary values of the difference. In addition, each computing unit preferably includes -accumulating H, _shade extractor, and -scaling unit. Between M 'samples relative to the received fetch sequence, each accumulator takes the sum of the sequence of preliminary values, and accumulates the sum of the difference of the same index to generate a cumulative value, and the accumulated value is a complex number. Every angle Γ -------- tl --------- CPlease read the notes on the back before filling in this page j

57 ^: 4 specifications (210 297 mm) 589812 5. Description of the invention (4 The extractor is used to obtain the angle corresponding to the accumulated value, and each zoom unit then uses the corresponding angle as -spin and then outputs it as-preliminary frequency Offset value, where the factor system corresponds to the above-mentioned index difference, and these different calculation units generate a plurality of preliminary frequency offset values. The weighted transporter then performs a weighted average operation on these preliminary frequency offset values, and estimates the frequency by: Lai Jian. Printed by the Intellectual Property Bureau of the Ministry of Economic Affairs

Implementation methods make the above-mentioned objects, features, and advantages of the present invention more comprehensible. The preferred embodiments are described in detail below with reference to the accompanying drawings, and are described in detail as follows: 1. The disclosure of the present invention-a so-called " The state-based differential accumulation (secret encounter alaccumulat leg, SDA for short) algorithm is used to estimate the frequency offset. The introduction of the lion performance and its scale derivation will begin. Assuming that the channel change is slow enough, the channel can be regarded as unchanged during the observation period. When continuous, the received signal ^ is expressed as dO = Ae ^ e ^^ g (t ~ kr) + w (t) k = --Oo A represents the channel gain and is scalar (scaiar) Θ represents the phase shift represents the angular frequency offset dk represents the kth data symbol transmitted (symb () 1) g (t) represents the comprehensive transmission The equivalent impulse response of the receiver, receiver, and channel τ represents the symbol period " w (t) represents the additional complex noise at the sampling rate = sampling _, strict_bu receive sampling (received bridging sequence rW where

/ 1 η 'Τ ~ Μ

Aeibe j (〇d " BU X. τ 'Μ

589812 A7

* =-〇〇 Ae e M kg \ nkM \ + w \ n \

\ + W r Τ λ η · -— J V M J where

Ω " represents the angular offset of a symbol period g [nhg {t \ represents the discrete-time signal paid by § (t) Anhw {tjtjL U 丨 ^ represents the discrete-time signal obtained from w⑴ , The impulse response will be limited by the length of the 灿 can double symbol period. In the case of, suppose ^ ^] = 〇, V ^ {〇, l, 2r .., (ZM-l)} if + W 啦 2, · ._ '(Μ-1)}, then the received sampling sequence becomes r [M + /] = AeJseJ ^ ^^ g [(/ _ k) M + ζ ·] + U-l τ LJC Please read the note on the back first Fill out this page again for matters} · _ Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs where X {Sl} i) = AejB Υ ^ ά ^ [(ΐ ~ k) M + i] k: 卜 L 合 '而 ， _ίΓ ~ Is defined as the state of the first symbol period, that is, the symbol is formed by the data symbols of the past_poor material Fu Zhougu. Qingmuguan item I can be seen that it depends only on these L + 1 data symbols. The same i and the same state receive # can be used to remove the influence of the channel and the offset of the estimation rate. If the noise term is ignored, for any & = \ /, in the pair loose + '.] And also μ 4 After performing the difference operation between the two, we get = Αΐ2Μ + i \ r% M + z] =. \ X (siifi) 2 ^ ^

The f-degree applies to the country ’s domestic fresh (CNS) A4 specification (2if 297 mm) :) Which 12 V. Description of the invention (6), ^ indicates that the transport rate of the complex conjugate is shifted, so it depends on In the following formula, the angular frequency offset is η-1. The angle contains the frequency Δ / Άλ / and the missing t-Zl is called the index difference. Estimation management; the operation process contains noise factors, in order to reduce the addition of a differential operation caused by the noise term === the estimated accuracy of the setting can accumulate the difference results before taking the angle for different financial introductions (not coh⑽) The reason for the magic is that the above-mentioned meter and Chuan's cable are accumulated separately, so the accumulated value κ (Δ /) can be obtained from " °, for the same △ / M- \ where 'internal sum,'-! , The 'external sum' of the same shape J is combined between the M samples of the solid data symbols, and the Σ§ 'accumulates the value of the phase difference, which is the sum of the index difference △ / of the internal sum table. Therefore, the estimated frequency offset can be calculated from the cumulative (Δ /) spoon cumulative force W ± ν (Αή ¥ out of the column accuracy caused by phase wrap (PhaSeWrap.und), the angle is limited to π and Y , So that the domain analysis surface of the estimation device has only △ / with too large difference value to avoid the case where the analyzable range is too small and the frequency offset is small. The reasoning is large: the difference △ / obtained by different The weighted average calculation of the frequency offset estimation value is as follows: ΥΑ 晴 The paper size is suitable for the standard (CNS) A4 specification ⑵g x 29 ^ 7 ^-

▲ --- ^ -------- (Please read the notes on the back before filling this page) _ ·

589812 A7 B7 V. Description of the invention (7) Among them, C (A /) represents the cable corresponding to Δ / = 1; ···· t said; 丄, difference, the weighting coefficient of the surface, and choose Δ / dirty, Restrictions on financial statements must be considered. In today's Hu Shidou fighters & ^ 隹 ° and estimation device, not only must consider the complexity of the implementation of the weighted average operation, but also urge the use of Θ practical training coefficients to reduce the estimation error, take an early Ways to describe _ equal weights, or prostitute weighting coefficients are proportional to the number of occurrences of the corresponding △ /. If the data can be used, the weighting system / 2 t is 1 otherwise, the counter is used to dynamically obtain the number of occurrences of each △ /, and then the value provided by the count Θ is applied. To generate weighting factors. When the size of the data symbol set is <, the possible symbol state reaches < ， RR [lM + i] = d] · r [lM + /],

k = l—L coffee + z] A1 · RJ, where = (d; d, L, d; d, L +], ..., d: di} = d;. {dii di ^ (... > ^} = J; ^

It is known from the above that rotating the receiving sampling sequencer will cause the same phase rotation of the symbol element, and the state after rotation becomes I di-L > d] d, _L + x r-, d; d] =, d: d} _L +] r-, \ d \ 2)

R.I

S As far as phase shift keying (pSK) modulation is concerned, the last term in ^ is constant ^ so the number of symbol states is reduced by a factor of time. The more common way is to use the data & _ mapping function (mapping funetiQn) instead of coherent numbers. In the Spread SpeCtrUm communication system, if the periodic spreading code or spreading waveform and the frame of Lai Gang, the job priesthood can be regarded as a part of the pulse wave filter (1se shaPing) and is incorporated into Equivalent impulse response. Because the proposed structure of the present invention does not know the pulse wave shaping or the impulse response of the channel, the present invention can also be applied to exhibition (cns) a4 (210 X 297 mm)

589812 A7 V. Description of the invention (9) The current receiving samples and their associated current indexes, namely r [/ 2M + z ·] and / 2, are used to update the storage area of a relatively large amount. Next, the difference unit 13 performs a differential operation on 4 μ + (^ 7, [/ ιΜ + ζ ·]) for the same symbol state, so as to obtain a sequence of preliminary values as intermediate data. As shown in FIG. 1, the difference unit 130 includes a conjugate complex operator 132 and a complex multiplier 134. The conjugate complex operator 132 performs an operation on each of its input samples to generate a generalized complex number of previously received samples, that is, 〆 The heart + (1; complex multiplier 134 is compiled in the conjugate complex number operator 132, and the same is performed on each sample of its input. Complex multiplication cry 134 calculates the product of 4M + / I and +, as follows : 口 口 ～ 二 4 心 · Μ / # Μ, for 1KU,…, where represents the initial value sequence, and M is a positive integer. On the other hand, the current index / 2 and the previous index (will be sent to the subtractor) 190 to obtain the index difference between the two, that is, in the i-th figure, the distributor 160 is connected between the difference unit 130 and the plurality of calculation units 14o. According to the index difference Δ /, the distributor 160 will come from the difference unit 13 〇 preliminary value sequence ~ / forwarded to the corresponding calculation unit 14〇 In this way, each computing unit 14 is allowed to input corresponding to the current index difference Δ / of 1 ^. ~ Referring to Figure 3, each computing unit includes an accumulator 343, an angle extractor, and a scaling unit. 347. The accumulator 343 takes the initial value sequence relative to M of each data symbol in the received sampling sequence, the sum between the samples, and accumulates all the sums belonging to the same index difference to generate an accumulated value. According to the present invention, It is best to set a power operator 34 before the accumulator 343 to strengthen the frequency offset estimation device and improve its performance. The multiplication operation is 341, which is used to calculate the power of p power of each preliminary value (power) : Heart M /, heart t, for ㈣ 丄 ... heart, where P represents the power used to find the power and is an integer greater than 丨, for example, but limits the present invention, p 22 2. According to the above formula U is the power of the initial value sequence, so the accumulator doubles (U

(Please read the notes on the back before filling this page) __-------- Order --------- line

A7

589812 Accumulated value material Σλϊ (~ Λ / = 〇M'-ly Σ (%) P 'accumulates the internal sum of the same * △ /, and the accumulation of _generation difference △' =. According to the present invention, 'M, cannot be greater than M, and M, is equal to M She Gong and then 'transmits the heart to the angle, the extractor 345 serves as the above-mentioned intermediate angle earthenware 345 to obtain the cumulative value KΔZ) of the angle Zρ (Δ /) monthly. Ear H: Sum: Λ: and the number of scenes P'Al, and -π < ZP (Δ /) < π where " represents the initial offset value of the corresponding index difference Δ /. Some calculation sheets in the estimation device are used to obtain a preliminary offset value at 4 o'clock. The estimation device records-plus calculation! It is necessary to calculate the chain step offset money in 15 steps. The weighting operator 15 takes the weighted average according to the following formula: $ Shift value: eccentricity Ω ′ × ^ Τ)? ° (Δ /) 允 / Δ / where A represents the estimated frequency offset and c (A /) Represents the weighting coefficient of deer for each index. In this way, the estimation device can estimate the received sample phase offset value in the aforementioned manner. Fig. 4 shows a frequency offset estimation device in a reduced state according to the present invention. The same symbols as those shown in Fig. 1 represent similar components, and will not be described here. In order to reduce the number of symbol states, a special conjugate device and two phase inversions: 420 and 430 are added. The total destruction 410 is used to generate the current complex number of data symbols, that is, the phase rotation of the data symbol sequence of the phase conversion device 4 and the phase rotation of the data symbol sequence of the county. cns) A4 size (21ϋ χ 29γ public love j

ί ---------- φ -------- Order -------- "-face c, please read the precautions on the back before filling in this page) ⑽812 A7 Five Inventions (U) Applied to the status indicator 110 to receive the powerful material symbol sequence, and recognize the data symbol _ hate capitalist; In, multiply the conjugate complex number with the beautiful material symbol. After the postal mail M, the symbolic status after the conversion can be expressed as

RJ's fresh copy of Fu Yan. Transmitter sets the 42G wire to receive the sampling sequence as the second phase. The sample sequence receives the sampling sequence, and it is the same as the current complex number of Beco Fufan's. Apply the phase-received received sampling phase to the terminal. Suppose that the asset t is small, and the number of Fufu can be caused by

… The current Λ system is usually unable to know the received data character and timing information when estimating the solution offset, so it needs a non-data-assisted (track other than d, abbreviated = DA) type frequency offset An estimation device performs initial estimation for the off-channel. Since the received data symbols cannot be known, the demultiplexer training and multiplexer details of the state library at 12 can be deleted, and a shift register is reserved to store the received sampling sequence, although it is the first embodiment ^ In the modified form of the present invention, the _nda-type frequency offset estimation device mentioned above is still used. FIG. 5 shows the NDA-type frequency offset estimation area of the present invention, the difference single lake, the power operator 541, the accumulator 543, and Newty == $ 放 早 伍 547. The storage area 52 has M units to input the receiving sampling sequence in series. After receiving the M units, the receiving sampling sequence 7 is as follows: [translation of M samples to form a delayed sampling sequence] In this embodiment, The storage area 520 is a shift register of M units. The difference unit 530 is used to perform a difference operation between the two and + -M], so as to obtain the preliminary value of the f column +] as intermediate data. As shown in the figure, the difference unit so is operated by the conjugate complex number ## 532 and the complex number Multiplier 534, conjugate complex operator 532 is used to generate the delay 589812 A7 B7 V. Description of the invention (12) The conjugate complex number of the sampling order, namely 〆 [«-M]; The product of the two is as follows: and +] 二 «厂 士 一 Af] where 'η represents a discrete point in time. The angle extractor 545 can directly obtain the angle of this intermediate data, but it is better to add a power operator 541 after the difference unit 530, and set the accumulator 543 between the power operator 541 and the angle extractor 545. The power operation is used to calculate each preliminary value from the difference unit 530? The power of the power is (〃 [4 factory, where P is a power number, taking the output 2 as an example, the power operator 541 calculates the square of each preliminary value, such as ^ to produce a sequence of preliminary square values: 〇 卜 Μ ]) 2, assuming ρ = 2 Of course, the power operator 541 used in the present invention can be applied to yang. The accumulator 输入 inputs ′ from the operation difference to 541 and takes the sum of +] as the accumulative value: v = z ^ w / ί = 0 where ‘accumulate force V is a complex number. In other words, the accumulated value V combines individual samples relative to the received sample sequence M. Then, v is passed to the angle extractor 545 as the aforementioned material 'angle extractor 545 to obtain the angle of the accumulated value v, that is, π. Scaling σσ reduces the size of the / factory by 1 / p, that is, then:

-ZF

P Printed by the Intellectual Property Bureau of the Ministry of Economic Affairs and Consumer Affairs Co., Ltd. In this way, the frequency offset value Ω " can be estimated. In summary, the present invention has a relatively low computational complexity and can be easily implemented in integrated circuit chips. Furthermore, the present invention proposes a new hanging NDA-type fresh offset device, suitable for money series. Deflection_Preliminary, Although the present invention has been disclosed as above with a specific embodiment, the policy is not clear. The technical content of the hair, rather than narrowly limiting the present invention to this embodiment, any person skilled in the art, without departing from the spirit and scope of the present invention, can do this. The scale of the stretch is appropriate—use the national standard of China (CNS) A4 2g ^ Public Love) 589812 Printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 B7 V. The description of the invention (13) The attached patent application shall be as defined by the scope of the application (please read the precautions on the back before filling this page) Φ -------- Order ---------

16 This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 public love) 589812 Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 B7 V. Description of the invention (14) Brief description of the diagram The first diagram is the invention Block diagram of the frequency offset estimation device; Figure 2 is a detailed block diagram of the state library in Figure 1; Figure 3 is a detailed block diagram of a calculation unit in Figure 1; Figure 4 is a reduction according to the present invention A block diagram of a state-based frequency offset estimation device; and FIG. 5 is a block diagram of another embodiment of the present invention. Symbol description 101 ~ Sequence of symbol states; 110 ~ Status indicator; 120 ~ State library; 121 ~ First end of state library 123 ~ Second end of state library; 125 ~ Third end of state library 130 ~ Differential unit 132 ~ conjugate complex number operator 134 ~ complex multiplier; 140 ~ calculation unit; 150 ~ weighted operator; 160 ~ distributor; 170 ~ counter; 180 ~ shift register; 190 ~ subtractor; 210 ~ solution Multiplexer; 220 ~ multiplexer; 230 ~ storage area, 341 ~ power operator; 343 ~ accumulator; 345 ~ angle extractor; 347 ~ scaling unit; 410 ~ conjugate device; 420, 430 ~ phase inversion Device 520 ~ storage area; 530 ~ differential unit; 532 ~ conjugate complex number operator; 534 ~ complex multiplier; 541 ~ power multiplier; 543 ~ accumulator; 545 ~ angle extractor; 547 ~ scaling unit; ~ receive Sampling sequence; 4 ~ current data symbol; L ~ current index. This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) (Please read the precautions on the back before filling this page)

Claims (1)

: 、 Applicable patent scope ^ Frequency offset estimation-storage area suitable for inter-symbol interference channels, with M units input in series—take less include: Sampling of miscellaneous samples is used for -Positive integers; Na _ column, where M series-the first difference "Shan Fan 'Ri Lai access sample Lai and proceed-difference county, _ 剌-# 步 值 序 取 # 作 = an angle extractor between the two , Used to obtain the intermediate data and 2. If the scope of the patent application is the first and the last, it is used as a frequency offset value. The unit to m has the right solution to the miscellaneous set, the above-mentioned difference, and the -total number of complex operators, use To generate the total number of annihilation of the above delayed sampling sequence; : Power frequency; partial T device 'at least includes: The upper frequency of the Lele phase can be multiplied by /: material, the rib is calculated from the above sub-unit {u [n] jp = (r [n \ r [n where ^ Table finds the power of _ power and is greater than the integer; and I ------ —____ 18 paper size 589812 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs ^ ~~ Σ (7 ^ 72) 'r * \ n ~ M ^ f is the frequency offset estimation device described in item 3 of the patent application of Weiyue, where the above Power number p 6—A kind of _offset estimation device suitable for the liver and bribery, including at least: the state indicator “receives a sequence of status signals from one of the ancestors, the state, and the symbol element status by # ^ ^ Table—Symbol-like symbols are defined, of which, a first positive integer # 付 Wu and L are close to the received data-"Library, with input-the _th_end, input of the receiving sample sequence The third end of the status signal of the person and the input person, the current index is the same as J == coffee from the butterfly-maid's head _ correct ^ to take == New Γ and the current number of data symbols with the same M state Previous Received Sampling and Previous Indexes, where M is the second positive integer, and He Yuan 'uses the above received samples in the received sampling phase. The current received samples are equal to the above, and the same state as the library fetched. The M samples receive a difference / knife difference between the two, and then obtain a preliminary value sequence to be used as intermediate data. · A number of computing departments, according to the above The M quotes associated with the current receiving samples and the Wei Wei index difference with the previous symbol status. The above calculation unit receives the preliminary value sequence corresponding to the index difference, each-the above calculation unit Contains at least an angle extractor, which is used to obtain the corner data of the intermediate data (please read the precautions on the back before filling this page) # -------- tr --------- The dimensions of this paper are ingenious ;: Fresh (CNS) A4 specification ㈣ 589812 VI. Patent application scope Frequency offset 2 is-preliminary frequency offset value 'These calculation units are used to generate a plurality of preliminary one weighting operations ϋ, # 初 钱The frequency offset generates an estimated frequency offset. Ding Jiazheng's average calculation is based on production and inventory, and the system is based on the detailed information. _Estimation Set, it is expected that the above state is hard and hard, and 11 is stored in each storage area. Samples of M first secrets and their previous materials; read% 'and take on the above-explained multiple jobs n' according to the above-mentioned status, the above-mentioned current down-sampling and systemic alliances are referred to as the transfer of wealth. Above; one of the above status signals represents the meta status :: == :: £ election: the above status signal _ previously received samples and their associated first 4 ^ above quoted the output of this storage area depends on the above The above-mentioned difference is the same as the above_fine__ 8. The frequency offset estimation device unit described in item 6 of the scope of the patent application at least includes: ^ 'complement generator' for generating the sequence center from the above scales A total of the above-mentioned previously received samples; from the uncovering method 11, followed by the listening operation 11, use the M in the above received sampling sequence to calculate the above current received samples and the status of the same symbol. ^ The product of the total minus layers, the money is the upper axis step value, the multiplication i is · 20 paper rule CJNS A4 specification (21〇 X 297 ^^ 7 589812 A8 Βδ 6. Scope of patent application ΛΓ-] Gan · Zhong, _ βη ji〉: ν ϊ, δ /} • L 'Compared to M of the above-mentioned receiving sampling sequence, each sampling division is the ZZkJ center and the' &quot; ° , Then accumulate the same index: = 1Γ state ΪΓ;-the external sum, the hand 'is the cumulative phase is the sum of the phases, and the ring representative corresponds to the above statement = patent, the frequency offset described in 12 items is estimated:-«上 上: Two:; = two, after the angle extractor,, the output after the sub-set is used as the above-mentioned preliminary frequency skew /, the above-mentioned _Δ / in the middle of the sub-shop and the product of the above-mentioned power Zheng. 14. The scaling unit divides the accumulated value _ by the product of the power P as described in item 13 of the scope of the patent application, as follows: The edges are corresponding to the above-mentioned index differences △ / and _t = — ~ Zv (ai) P, A, and -π &lt; Α (Δ /) &lt; π where 'ZΓ (Δ /) represents extracting cry right from the above angle _ ===== Estimate_, where the above plus Take the weighted average to produce the above-mentioned fresh offset material values: 〃 〃 _ step solution offset value ω, ς 4τ)? Φ /) << Δ / where Ω &quot; represents the above-mentioned receiving sampling sequence shown above-«leading difference △ / The pair of Wei Ding «is the # Γ shifting material value, and coffee) Table 16. The offset count benefit as described in the item m_ of the towel" used to generate the above-mentioned receiving sampling sequence "m to) contains-the above The current index. The paper size associated with this item's order is applicable to iiii standard (CNS) A4; fFS 22 X 297 mm) A8 B8 C8 D8 Sixth, the scope of the patent application: The Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs printed the patent application item No. 6 Sakura's bias. Set 11: 4 to generate the total euphemism of the current data symbols above. The sequence is applied to the above! ^ Rotate vertically and move the shovel, 苴, 、, +,-to produce the above-mentioned status message to Li. The sequence contains the current data symbols and the L most recently received. And the reversed data description is that the current u sequence is the form of the above-mentioned data multiplied by the above-mentioned data of Fu Lin Column and the above complex number of vehicles; and === The frequency offset estimation device described in item 1G of the Post Office 4 patent, wherein the above-mentioned screen number P is equal to two. 19. A type of frequency offset estimation device suitable for an inter-symbol interference channel, including at least: a storage area 'having M units inputting a receiving sampling sequence in series for generating ~ receiving samples by flat sampling— Delayed sampling phase, where M is a positive integer; a one-to-one difference unit, which is used to perform a difference operation between the received sampling sequence and the delayed sampling sequence to obtain a preliminary sequence of values; Differential 'is used to calculate the power of ρ of the preliminary value sequence, where ρ represents a number of scenes of long multiplication screen and is an integer greater than 1. An accumulator is used to calculate the power of P of the preliminary value sequence. The power is an accumulated value relative to the sum of M and the received sampling sequence, where M ′ is a second positive integer and the accumulated value is a complex number; an angle is extracted to obtain the accumulated value Angle; and (please read the notes on the back before filling this page) 589812 Patent application scope A scaled unit rate offset estimation value Sub-unit 1 ^ = approximate _19 the solution of the offset estimation device, Use 乂 to reduce the angle of the U value by a ratio of 1 / p to generate a frequency where the above-mentioned differential conjugate complex operator is used to generate the above-mentioned delayed sampling sequence of a total of 1¾ complex numbers; the above is calculated by the -1 multiplier rib Receive the product of the sampling sequence and the complex number of the total delay, and output it as the initial value sequence. The product is X: 1 u \ lA ~ ri77] · r * \ n -M ~ \ &quot; represents the above delay The conjugate complex number of the sampling sequence, [,] represents the above column, and η is a discrete-time argument. Initial value order and (Please read the notes on the back before filling out this page) f Order --------- Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs This paper size_China Standards (CNS) A4 Silk ㈣χ 297