1、Implementation of ST FSK Detection Based on Decoupled Maximum Likelihood Detection Gao Yuan-yuan Shen Yue-hong Hu Xian-bin (Department of Radio Communication /CE, PLAUST, Nanjing 210007, China)Abstract This paper presents a decoupled maximum likelihood(ML) detection algorithm, which utilizes the ort
2、hogonalcharacteristic of signal, decoupled the combined ML detection into separated one, under the assumption that CSI is knownat the receiver. Utilizing appropriate channel estimation algorithm, the decoupled algorithm not only sharply reduces thecomputational complexity compared to the noncoherent
3、 ML detection, but also improves the performance. Simulationresults confirm the effectiveness of the algorithm.Key words Space-Time Frequency Shift Keying(ST-FSK), Unitary design, Decoupled Maximum Likelihood (ML)detection, Coherent maximum likelihood detectionPreface The FSK makes a way is high bec
4、ause of its power utilization, be subjected to the limit letter way in the power thusWin to get extensively applied, if the military corresponds by letter to correspond by letter and satellite, cultural heritage have another antennaThe empty hour codes the technique and FSK to make a technique to co
5、mbine together, acquiring many antennas to bring The cent gathers to increase a benefit, in the benefit decline the letter way under condition didnt need letter way information, can adopt not Concern with of biggest however(ML) the detector fl. Cultural heritage2)put forward to use matrix is hand ov
6、er train g le Re solve(QR)calculate way, Be DO I n g not lose the premise of the system function under, lower an operationQuantity, simplify to carry out the complexity of that ML detector. This text puts forward a kind of separation ML signal examination method, being believing an appearance in f o
7、r ma t o n The F know of under assumption make use of to send out signal is hand over sex characteristics, make many receive The ML consociation of the quantity examination the problem separate for some vectors alone the ML examination ask .In operating quantity not only consumedly low in above two
8、kinds of not mutually thousand examinations, and get G e t the exaltation of the function big in 3 d B o s Adoptions separating the main characteristics of the ST FSK ofwith the ML examination method BE:(1) a do p t Use the real amount full speed rate is hand over a design, be to send out the antenn
9、aAcquire the full marks gathers to increase a benefit;(2)ST-FSK with is hand over FSK to make to have a homology e s p e c I ally O rd e r, then when enter to make a number to tend in endless, can approach the mountain agriculture extreme limit, but with sacrifice The bandwidth usefulness for price;
10、(3)the wood text put forward of the separation ML examination method and text Dedicate1,2 in of concern with the examination method to compare not, one is a function to is big in 3 dB of good Place , can make to translate the code complications moreover from with send out antenna the index number re
11、lation to reduce for Present 、In order to concerning with an examination to need to know the letter way an appearance information, the above-mentioned operation measure of let up Didnt consider letter way to estimate value operation to measure, consider M to send out the antenna N to receive a day L
12、ine of the MIMO flatness decline the letter way, letter way the variety is opposite to compare slowly, letter way the estimate of adopt While using according to the calculate way of train the sequence, complications and MN that believe a way to estimate to be worth a machine become just Ratio still
13、is the line sexual behavior namely: if synthesize to consider the letter complications that estimates value to bring,In the antenna count with the FSK enter make number to compare a hour, concern with complications of the examination not slightly low ,Along with the antenna number with enter to make
14、 to count of increase, complications that concern with an examination is obviously low in not Concern with an examination. Mathematics sign meaning: With mean respectively the matrix or vector turn to place With grip to turn to place totally ;the mean the K r one product;.II; mean Fr ob e n us Numbe
15、r; ma cal element;month, mean the row vector k chemical element: the IN mean N rank unit matrix .Want to send out the signal matrix to carry on to all to be whole before not adopt the simplification calculate way Search, again because of the full speed rate design, P=M, as a result complications alo
16、ng with send out antennaAnd enter increment of make the number to present index number to add doubly. Our adoption and the cultural heritage 川 is similar to of the letter way model. Consider a MIMO System, have M to send out antenna, the N receives antenna, the assumption is sending out T The letter
17、 way of antenna inside the time length of the sign for flat decline(the frequency chooses notSex)the letter way. The vector of the signal mean form is :BE receive antenna the last TXI receive signal row The quantity, the x, sends out antenna, the last TX t sends out signal row vector .Spirit. Mean F
18、rom send out the falling off path that the antenna m arrives an of receive the antenna n to increase a benefit; for receive Antenna .Ascend of add sex voice, can distinguish model to change in to all be worth for., The square is bad for cloud, The independence of the hour distributes together of rep
19、ly Gauss to change quantity random. The matrix of the signal means the form is a Y-XH+E, its towel XBE the IXN flatness to decline letter a way characteristic matrixThe TXN adds sex voice matrix .At the matrix Y, in the X and E, the level direction mean empty Distribute, the perpendicular direction
20、means time distribute. The S is 1= FSKBE a contented real amount is hand over design of empty hour make, then send out signal The matrix satisfies Ax is a signal horoscope diagram among them .Adopt the K enters to make FSK to make, defining a FSK wave form to gather for The horoscope diagram of the
21、ST FSK is Become the P row vector, each chemical element in the row vector draw from Send out signal matrixMake with empty hour code of process .At each a FSK wave form sent out to send out in the signal matrix the number is a P.A, is positive for the P x M real amount Hand over the design matrix, s
22、end out the corpse a FSK wave form in the P the time length, because of This is the full speed rate the empty hour code, each form contains a sign, the signal of ST FSKD the size of the set as T-PKAl at to is hand over empty the ML of the code receive make use of BE hand over characteristic, separat
23、e the consociation ML the examination problem of several vectors thus for some Is mutually the ML examination of the independent AWGN letter way is inspire by that method,Const Pass by to deduce the separation ML signal examination method of the ST FSK 3 according to the ST-FSK receiver structure of
24、 the ML standard When assumption the letter way the H is to have already know, at this time of however function can such as cultural heritage Medium say. Biggest however translate the code standard i, among them k the vegetable take 1, other vegetables is 0.Can draw on these ST FSK according to sepa
25、rate the receiver structure that the ML standard concerns with an examination, such as figure e In order to receive antenna to receive vector, the v difference Y BEN the vector constitute of receive the signal matrix, carry on to the formation weCan think matches it to receive, chasing different AN
26、according to the above rule, the generation go acquire receive the signal matrix to resolve for the corpse independent row sigh, , to carry on the ML examination respectively all the way each time, can immediately be correspond of FSKSend out a form and send out sign to estimate a value, enter to ma
27、ke a conversion through K/2, get originality two Enter to make a data to flow of estimate a value a function is analytical From the type(4)with figure 2 medium can see, the wood text put forward of the examination method make ML examination mountain the consociation of several vectors examination th
28、e problem separate for the The respectively examine of the quantity problem, namely to each vector Cr that has been re- constructed. P The P carry on biggest however examination, we know in a send out the signal matrix FSK wave form of send out the number is a P, then receiving to carry to need to c
29、arry on a ML examination,FSK wave form can be estimate directly. Compute complications and P presents line Relate to, also be with send out antenna few Ms to present the line sexual behavior, along with send out the big line number The increment of the quantity, with concern with an examination notI
30、, zand the adoption all search of concern with examination to compare, Let up 3 complexity of the receiver structures and the calculation complications consumedly, but its premiseThe condition is to need to know the letter way an appearance information, so need to carry on to believe an estimate of.
31、 When Separate the examination method adoption according to the best method trained a sequenceecarry on believing a way to estimate a value Hour, its complications will have increment, supposing at this time from send out training sign to constituteThe matrix is a X, , correspond of receive the sign
32、al matrix as Yr, then estimate letter way for H=Y, take sentencing a FSK wave form as standard, comparisonThe separation examination method and cultural heritage that this text put forwardconcern with an examination and adopt not in 1,2 whole Search of concern with an examination to translate the co
33、de complications, the result From table 1 can see, be adoption all search to concern with examination it translates code the degree and cultural heritage of concern with an examination not equal; cultural heritage2 in of not mutually thousand examination The method compare above two kinds of complic
34、ations have to lower ;however this 3 kinds of methods of the operations re miscellaneous degree all becomes a direct proportion with KM, namely with send out the antenna number to present the index number relation; but adoption centLeave the ML receiver structure, operate complications with send out
35、 antenna to present line sexual behavior;Among them mean according to train the sequence letter way complications for estimate.WithK-4, M=4(P=4), N=1 is example, only consider multiplication operation, 4 kinds of squares Method from go to bottom up of operation quantity respectively is 17408. 15872.
36、 17408 and 2628.Can see complications of a separation ML examination calculate way reduce the I piece quantity class.Among them p=the M /hour for each a receive the letter ratio of the antenna(SNR), Under the sort circumstance There is the direct relation expression type, therefore very difficult fu
37、nction compared both directly. But textDedicate3 give function that have already known H under the certain condition compare and dont know H about Hour of function like 2 doubly, to single importation list output the FSK make of imitate true enunciation, at Medium etc. letter the compare the hour co
38、ncern with examination compare not concern with examination function good about 3 dB So IC an estimate to under general circumstance the advantage concerned with an examination to bring should be big in the list Antenna of 3, but cant attain so good function of 2 M N s, either. Moreover accurate Of
39、estimate of can Be giving to settle under the parameter circumstance, compute an all strange values to acquire. Such as for M=2 Ns=1 of circumstance, adopt the most in common use of hour postpone the best whole hand over a design actually, Of biggest be worth for the 1/x/2.Again from Aarrive To k al
40、l combinations carry on a calculation, can get X most Greatly strange value is ten thousand, while attain the same mistake code function top boundary, comparison the type and type, can be concern with the examination letter ratio and concern with an examination letter a ratio notSeveral of the relat
41、ion of =P/Z(1+2 pus) be, concern with the examination ratio to concern with the examination function not on the wood can good 6 dB o But because of type(9) is according to the comparison of the mistake code function top boundary, the both sexes can ascend the boundaryLoose tight the degree is differ
42、ent, so with actual the function contain certain difference, passing a following calculation The machine emulation imitated to really give confirmation, the a function difference is or so in the 3 dBs.Request.6 be over languages Imitate a true result We verified the wood text to put forward first of
43、 the separation ML examination calculate way and adopt whole Hour of the ML examination search of the function is completely consistent, agreeing with the theories analysis .Then We to M=2(as a result P=2) and K=2(as a result T=4) of the ST FSK ado p t The function that concerns with ofwith the sepa
44、ration ML examination method that the examination and this text put forward not makeImitate a true comparison. For simple rise to see in all l y imitate really all suppose receive the antenna number for1, the letter way is an AWGN flat benefit comedown the letter way, and protect in time length T Ho
45、ld constantly, separate the ML examination method among them respectively imitate really believe a way and estimate in the idea l A cc the letter way under condition of function. Imitate a true results h as figure,3 show .See from the diagram, Ideal letter way under circumstance concern with examina
46、tion compare not concern with the function of the examination good about3 one 4 dB When adoption according to train a sequence of the letter way estimate a value, and train a sequence to have hairSend the sign ratio to concern with the examination function for the l/20:00 than under ideal circumstan
47、ce the function Lose small in 1 dB .The diagram is 4 right nesses of Ms=4, P=3 and K=2(as a result T=6) of ST FSKOf imitate true enunciation, medium etc. letter ratio hour ideal letter way under circumstance concern with examination the r 匕 not mutually The wood text puts forward a kind of ST-FSK of
48、 according to separate the ML signal examination calculate way ,Not only can simplify the receiver structure consumedly with lower to translate the code complications, and get can Get the exaltation of the function .When the letter truth thinks the F know, the flat benefit declines Believe a way to descend with concern with the examination calculate way It z not 1 compare to acquire of the function increase a benefit big in 3 dBIf adoption according to train sign of the letter way estimate value calculate way, separate ML examination of complications The degree still ca