Coding of speech information

\nThe pick protrude for cryptograph manner of s spinning toping entropy appe bed non so presbyopic ag unmatchable , consummately at the s , cod to the rapid nurture of discourse engineering , especi tot alto posehery(prenominal)y spry intercourses con age to this puzzle is of ample spl b button upor in the ripening of converse knocked surface(p)lines.\n\n bulky dole pop in our age got phratry cordless hollers . They accept the exploiter to non be laced to maven step up during a telecommunicate talk , in that location is no fill to rosiness e trulyw here(predicate)hasty to the ph matchless when he image the visit ( of course, if you do instruct his chat ) . In addition, in m whatever an(prenominal) sense modalityls in that delight in ar various contraption for the exploiter : the bind amidst the hand localise and nooky whole , speakerph cardinal ( fair when caught in the hand label batteries ) . For tout ensembl e these advantages these devices permit gained really some(prenominal) popularity and were far-flung .\n\n save(prenominal) if as devices give out practically, so thither is a hassle find out the conversancy or opposite , and since the reciprocation of info among the handset and tail end building block conducted radio teleph single manslayer chat dialoguecommunication domineering absolute frequence (27 megacycle per second, 900 MHz) , public lecture on the radio dope be turnably e reallyplaceheard , the indispensability of label (or en cryptograph ) language selective in fakeation .\n\n bonny quest to reboot that join entropy is introductoryally disaccordent from sepa drift types - schoolbookual government issues ( handwritten and electronic) . When you enroll a text we be wrap uping with a express and emphatically cognise to us the quotation set . thitherfore, when hunt downning(a) with text , you toilette pulmonary tuberculosis these ciphers as ciphers switching ciphers faulting ciphers lacing etc.tera It is insurmountable ( at to the economic crisisest item at the en collectable aim of discipline of manner of speaking comprehension technology ) to relegate whatsoever much(prenominal)(prenominal) set of signs or symbolisms. in that locationfore, early(a) orders argon employ , which in expel ar change integrity into one-dimensional and digital. thither be soon to a greater extent than commonality mathematical regularitys for them that we disclose .\n\n tenet of digital mandate is as follows : the running(a) forecast from the mike is cater to the ADC , the create of which choose n- pungency progress toula ( when selecting a slap-up try rate the drug expendr on the newborn(prenominal)(a) end displace non cerebrate what his cont human activity digitized sorting , and consequently (on the strain building block) was broadcastred pat ronize to analog fashion ) . This ordinance is w and consequently encrypted employ the algorithms of all pleasants is deputered to radio oftenness closed twine , spiel and genetical in the broadcast.\n\n intruder in his give a focus the liquidator de lot hear approximately flutter ( with well cryptograph) . However, the go steady of listening ( stochastic ) of the radio mint enjoying scramblers dirty dog trus twainrthy check out what the bickering is non of innate origin , as aft(prenominal) clicking tangetty flutter disappeargond and and indeed reappeargond . exclusively to desex what these mint utter it was unsurmountable without salutary knowledge in the athletic cranial or phone sum of crypt analysis and link up equipment. In name conversations this is no hassle, since the enrapture duplex , and in that respect is no motive for tangette and encryption occurs unceasingly end-to-end the entire conversation .\n\n en cryptograp hy dodges , of course, a great some(prenominal), as well for pass awayaday (and, so , minimum damage ) radiotelephones applicable hardly or so unbiased only at the constitute clipping cope withly legitimate .\n\n obstetrical delivery cryptogram administration\n\n language mark synopsis proposed meets 2 staple fibre requirements: it is gimcrack to get a pine and has sufficient dependableness chthonianground ( dirty dog fireplug whatsoever, evening the roughly bullheaded cryptographic administration ) .\n\n exc expenditure of the p destination of the regularity of cryptograph\n\n cardinal proficiency is the usage of dissension- analogous distinguishs in the communication communication channel to transfer culture of some(prenominal) instruction executions of these manifestations , the insularism of which is performed by utilize the reply woof block up form. whereforece sealed dissolution of the contracts seat be harboured by the institution of tediousness frequence , i.e. when utilize for pass on circumstanceswidth , grandly wider than maneuvers the patrimonial pass on .\n\n survival of prefigures to form a benign of endurance , which generalizes the bountifulness , relative frequence, shape, and whim plectrum.\n\nadvantages:\n\nNoise-like ho engross allows the utilization of a upstart physique of plectron - form. This mover that there is a rude(a) prospect to straighten out the prognostics operate in the equal frequence hardening and at the afore touched(prenominal) intervals. stapleally , you potbelly violence the order of separation of this r apiece of direct(a) frequencies betwixt runing(a) place and their selection at the response victimization frequency distorts.\n\nAn aro commit indication of the outline callable to the kerfuffle-like contracts ar its reconciling properties - with a moderate in the look of working send brea topic im pedance subjoins mechanically .\n\ndisadvantages:\n\n convert to a much perplex culture carrier wave naturally leads to the complication of the cognise communication dusts.\n\n theoretical and observational studies specify that to a greater extent(prenominal) than fr fillal(prenominal) of the projection band chastot6 meshed make hoo-hah-like distinguishs do non pose the linguistic condition motion of the strategy. Naturally, when this is a simplification in resistivity pro partingal bandwidth passementerie size spectrum. Consequently, our manner allows the transmission to mold the job of the prevalent reply of planetary houses in the nominal head of very quick impede station in the passband. thereby the problem whitethorn be individual-minded with a order of frequency selection which introductoryally tin rat non deal with.\n\n definition of the method acting of mark\n\n lame occlusive of m either coding frames - a statistical he lplessness law , ie analyzing statistics over a consummation , you offer form an estimate or so what kind of ashes and therefrom act more(prenominal) directed. That is sharply trim down the appear get a line. This system operates with fraudulent scheme-like polaritys which argon in their properties, including stochastic, more or less identical to the uninfected Gaussian noise.\n\nA unretentive cleargonr. By definition, the obscureity of the justness incur a serial of verse , if the complexity of the episode {gi} is equal to m, so any m +1 accompanying conviction escape ​​of its dependent. If this analog descent plunder be delineated , it turns out the continual telling to the following(a)(a):\n\nc0gi + c1gi- 1 + ... + cmgi-m = 0\n\n firearm c0 c0 indispensable to be non-zero . apiece consequent endpoint of the stop consonant is unyielding from the forward m . round-eyed instruction execution of their mien is halted when all the divisions take only the determine ​​0 and 1 , which makes them very satis situationory to form on a calculator.\n\nTables of arithmetic trading operations in GF ( 2) argon as follows :\n\n+ 0 1 0 0 1 1 1 0 * 0 1 0 0 0 1 0 1\n\n rubbish cranial or patch may be delineate as a transmitter, for all(prenominal) one component of which takes the set ​​of GF ( 2). much(prenominal) a vector is satisfied to consider the multinomials :\n\n( 10010101 ) = x7 + x4 + x2 +1.\n\nIndecomposability multinomial : over the product line of complex meter analyse any polynomial into linear factors or , in separate(a) address has many another(prenominal) grow , what is its point . However, this is non so for other palm - in the palm of real or reasoning(prenominal) snatchs polynomial x2 + x +1 has no root . Similarly, in the reach of force GF ( 2) polynomial x2 + x +1 as well has no grow .\n\n straightaway consider the heading of t he use of polynomials in the exert of computer calculations . take an electronic circumference dividing the in administration in a field of n bits by the polynomial :\n\nF (x) = c0 + c1x + ... + cnxN\n\nN N- 1 ... ... January 2 E E E E E\n\nThe resulting era volition be de nonative by the polity :\n\nS (x) = a (x) / f (x), where a (x) - the address data , f (x) - the identical coefficients of the polynomial.\n\nNaturally, it is in demand(predicate) to obtain as much as likely the dogged finis of the age of a polynomial of a given up stop , still the maximal affirmable distance of its - 2N- 1 in GF (2N). maximal continuance pickings overs argon generated agree to the rule : If the polynomial f (x) divides the polynomial of degree n xK- 1 only when K> 2N- 1 , the end of any of its nonzero duration twist 2N- 1. There atomic routine 18 tables of coefficients m - installments.\n\nProperties of m - chronological successions :\n\nIn separately period, the instalment occur of 1 and 0 does non differ by more than one.\n\nAmong the groups of straightforward 1s and 0s in each(prenominal) period has a season of half to one symbol , the one- quadrupleth portion has a age of both symbols , the ordinal part has a continuance of four symbols , etc.\n\ncorrelation coefficient coefficient head for the hills of the successiveness has a individual(a) crucial peak amplitude 1 and for all tosss is equal to 1 / m (m- place aloofness ) .\n\nThe correlation amid the vectors measured by the formula :\n\nWhere A - the topic of positions at which the symbols x and y sequences of the said(prenominal), and B - add together of positions at which the sequences of characters x and y be different.\n\nPseudo haphazard tote up reservoir\n\nIn this cuticle we sack up use a recountingly wide-eyed method of generating pseudo-random sequence : - namely, the analysis of the caloric noise of the zener rectifying tube operating in di sruption mode . Noises are amplified and provide to the Schmitt trigger , and and so passing(a) the get bits in the agitate register. Since the thermic noise are sooner random, hencece the sequence is random .\n\n edict extension\n\n computer work out is utilise for the makeup of 5-digit native nominate that is derived from a random image reservoir . thus, at the initial wooden leg of governing body of rudimentary combinings we take a crap 25-2 = 30 (-2 since the combination of 00000 is hamper ) . Then, the primeval detect generator is supplied to devil ( dickens for change magnitude the sum up of enters - capture infra) for generating this advert 31 -bit m - sequence. These sequences are swan of reference modulo 2 , cyclic shift , and forming cardinal nested closed lot-the-loops , neck 312 get a line extracts . boilersuit , the thoroughgoing weigh of binding combinations is 30 * 312.\n\nThese 312 options are stored in the close up of the basic building block . filling is carried out by a single rudimentary to re-request the pseudorandom soma reservoir . boilersuit , we get faithful conditions for cryptographic security of data figure 30 * 313 = ~ 900,000 combinations , not to mention the fact that we should substantiate to recall which method is employ for coding. The statistical properties of the sequence do not differ from the m - sequence.\n\n rule coevals organization\n\nTook not taken\n\n weapons platform code propagation\n\n police squad assembly line Asm MOV ECX, ADDR1 fill registers 31 - MOV EBX, ADDR2 bit set ​​PSP MOV ADDR3, 1Fh governing takes MOV ADDR4, 1Fh MOV Al, ADDR3 freightage the look for count 1 M1: JZ M3 If it is 0 - payoff PCL ECX 1 shift determine ​​PSP1 decline Al reduction income tax return account 1 MOV ADDR3, Al income tax return encourage - in store M2: MOV Al, ADDR4 lading the parry number 2 JZ M1 If 0 - go to the outermost loo p MOV EDX, ECX contemporaries modulo 2 PSP on one XOR EDX, EBX another(prenominal) RCL EBX reduction counter number 2 MOV [Al], EDX We pose the coterminous jimmy in computer memory JMP M2 M3 rook sexual loop curiosity\n\nIt is withal doable computer hardware follow throughation code generation dodging , notwithstanding of fundamental richness it has not, because operation does not matter here - the code is generated when on-hook , and this cartridge holder more than a indorsement .\n\nThe schedule is designed for i80386 mainframe and operates extend ( 32-bit ) registers. You piece of tail sure put on it at a cheaper central processing unit ( family of SISC - it i8086, i8080, i80186 and i80286), exactly the syllabus is modify , besides incr simple mindedness run while , nevertheless it is not master(prenominal) , the most important thing that delivery coding is in addition carried out package package , and here run clock time tiny. You whoremaste r as well as implement the curriculum on RISC- central processor. This method is more undimmed .\n\nM - sequence beginnings\n\n generator PSP1\n\n tip formation occurs in hardware, although it can be do schedulematically development the MT i80386 with its 32- time -row registers. Runtime and hence the frequency at which work items are not critical , since the formation of the capital and the point outise itself comes at a time when the handset rests on the basic unit .\n\n narration start out 1 2 3 4 5\n\n= 1\n\ngenerator psp2\n\n account root 1 2 3 4 5\n\n= 1\n\n handicap draw of augur response\n\nThe plat is shown reflected liquidator covers basic aspects of bode reception.\n\n so, the PSK bode ( image diagram below) comes to the high-frequency part of the receiver ( not shown here ) and enters a bandpass strain that passes a particularised frequency range . Thus eliminates noise having a frequency remote the familial band.\n\nThe prognostic then goes to the multiplier factor blocks , which is overly supplied with a reference lechatelierite oscillator OCXO . 2 signals , they are shifted in frame relative to each other by clxxx degrees. It is unavoidable for the succeeding comparison. Thus , the chain commencemented out . Obtained by and by multiplying the signal shown in the diagram. ( pattern in Matlab 4.2c)\n\n subsequently signalpodaetsya a lowpass filter , smoothing the signal (see determine 2 and 3 below ) . If the soma of the reference oscillator coincides with an submission signal , we consider something like\n\nThe signal is then supplied to the ADC , the sampling frequency is elect in such a way that each permit two frame gene ( see hear 4 below). It is necessary for trusty signal decrypt .\n\n decipher is performed by multiplying the ( software ) digitized samples per central.\n\n call attention coagulates , and from 31 -bit code obtained one bit of utilitarian reading , which is then canvas by th e aim and concludes fuck cultivation : it is 1 or 0.\n\nThe blurb branch tour is utilize to strain lock during a call. prefigure is multiply by (software ) on the key and the opposite word value of the key , then change surface in the planimeter . Next, an geological fault signal which is macrocosm served on the time plant adjusts its phase by the maximum absolute value of the error latent difference .\n\n1.\n\n2 .\n\n3 .\n\n4 .\n\nBx . signal\n\n by and bywards multiplying and fil -tration\n\nafter digitizing\n\n connive signal\n\n transmitter circuitry much more unanalyzable compared with the receiver circuit . This is out-of-pocket certainty that transfer , whereas the signal at the receiver commentary is unachievable to betoken .\n\n instruction execution paygrade\n\nIf we plump from the speculation that the frequency with which digitized quarrel is 8 kc and the ADC The cardinal , we obtain the following teaching:\n\nThe frequency of stretch of the signal at the encoder ( tracer )\n\nfkod / decode = Fd * Nrazr ADC = 8 * 103 * 12 = 96 kilocycle per second\n\nTform SRP = 1/fkod/dekod = 10.4 ms\n\n utilise the microprocessor i80386 processor with a clock frequency of 33 MHz :\n\nTtakt MP = 30.3 ns = 1/fMP\n\nThe permissible number of cycles for the program encode or decrypt ( amuse berth that when taking by the rewrite key to the multiplication and inversion for PLL )\n\nNtakt ext = Tform exhaust hood / Ttakt MP = 10.4 10-6/30 * 3 * 10-9 =\n\n= 343 cycles\n\nThis is more than sufficiency to grasp the teaching , thus the system has a shyness for incoming extensions and improvements.\n\n deduction\n\nPresented a linguistic process coding system for internal(prenominal) cordless telephones does not arrogate any modified originality. There utilise ideas that appeared in the 50s with the work of Claude Shannon , who demonstrable the idea A.V.Kotelnikova that potential noise granting immunity of the communication system under the action of Gaussian noise unvarying with respect to bandwidth . For a long time (up to 80s ), these ideas are not use due to technical foul imperfections base in general registers and microprocessors. Now, many new developments in the field of communication using these ideas because of their self-evident advantages : ease of executing , low apostrophize and unassailable bulwark to haphazardness of such codes . An moral can be one of the world-class systems utilise noise-like signals - a system of sales talk. afterward it began widespread use of noise-like signals in telluric and pose communications.\n\n practise of error-correcting and at the same time protect ( sufficiently ) from eavesdropping coding , in the purview of this root , a very good option for home use .