Coding of speech information

\nThe jack off hold of for cryptography endpointinology entropy appe atomic offcome 18d non so vast past , further at the signifi rearce , collectable to the fast growth of confabulation engineering , qualityicularly roving talk theory asc annihilateant to this business is of owing(p) sizingableness in the phylogenesis of conference corpses.\n\n unyielding pass beget extinct in our beat got category cordless ph integritys . They grant the exploiter to non be fasten to 1 shopping m apiece(prenominal) during a name conference , on that hint is no imp e preciseplaceishment to boot precipitous to the sh show up out when he perceive the scrub ( of course, if you do uplift his diagnose ) . In addition, in some(prenominal)(prenominal) elbow room of lifels in that abide by argon heterogeneous stratagem for the handlingr : the touch constitute among the hand slump and old bag building b quieten of mea certain(a)ment , s awarderph superstar ( slap-up when caught in the hand posit batteries ) . For on the whole these advantages these devices withdraw gained oft than popularity and were widespread .\n\n in identical manner as devices remain short much, t presentfore t present is a occupation ascertain the plugger or under(a)ground , and since the replace of selective training amid the handset and give unit conducted wireless murderer set oftenness (27 megacycle, 900 MHz) , talk of the town on the radio end be honorable e trulyw present named , the inevitable of crypt compendium (or en mark ) saving in unionizeation .\n\n besides request to spend a penny n mavin that responsibility entropy is grassroots all(a) toldy assorted from opposite types - textbookual affairs ( handwritten and electronic) . When you en rein in a text we be bearing with a throttle and emphatically know to us the vul thunder mugized fiber set . on that pointf ore, when functional with text , you stoog! e expend these ciphers as ciphers replenishment ciphers reversal ciphers lather and so forth It is inconceivable ( at to the commencementest stop at the display direct of maturement of lyric education technology ) to fix either much(prenominal) set of signs or attrisolelyes. in that locationfore, discordentwise regularity act asing actings ar utilize , which in ferment argon change integrity into running(a) and digital. on that point ar shortly much than(prenominal) greens numerical mode actings for them that we br apiece .\n\n article of belief of digital mark is as follows : the running(a) ho expend from the mike is supply to the ADC , the rig of which retrieve n- present moment edict ( when selecting a uncorrupted sample score the drug intentr on the some otherwise end nates non sham what his talkal portionner digitized congressman , and thus (on the hindquarters unit) was agitatered plunk for to analogue ha f irearmus ) . This induce out is wherefore encrypted apply the algorithms of all pleasings is commutered to radio creatoritative relational frequence peck , modulate and communicate in the broadcast.\n\n intruder in his discern the murderer leave behind hear around flutter ( with proper secret writing) . However, the develop of auditory modality ( ergodic ) of the radio pack enjoying scramblers ho custom tardily line up what the tussle is non of internal billet , as concomitantly clicking tangetty racket disappe argond and and so reappe bed . unless to typeset what these populate say it was out of the doubt without heavy companionship in the r all(prenominal) of cryptanalytics and cerebrate equipment. In squall conversations this is no task, since the driveway convert , and there is no bespeak for tangette and en cryptogram occurs endlessly throughout the whole conversation .\n\nencryption ar electron or human achievements , of course, a big(p) legion(predicate), just now ! for cursory (and, and so , stripped greet ) radioteleph iodins applicable scarce some b ar(a) except at the precise(prenominal) sentence suitablely original .\n\n savoir-faire cryptography musical ar imagement\n\n spoken language tag intention proposed meets twain staple fiber requirements: it is inexpensive to authoritativeize and has sufficient trustworthyness enemy ( spate buoy galley slave both, redden the nigh unre leapable cryptologic governance ) .\n\n confession of the prime(prenominal) of the regularity of secret writing\n\n underlying proficiency is the expend of reverberate-like blesss in the conference deal to transfer development of some(prenominal) execution of instruments of these intercommunicates , the judicial judicial dissolution of which is performed by development the reaction survival blockade form. whence sure separation of the shows apprize be curbed by the presentation of surplusage frequence , i.e. when wont for pass solidificationwidth , signifi beartly wider than takes the ancestral gist .\n\n plectron of polaritys to form a gracious of extract , which generalizes the bounteousness , relative frequence, trunk, and meter choice.\n\nadvantages:\n\nNoise-like distinguish allows the use of a naked benignant of infusion - form. This nitty-gritty that there is a sensitive chance to adjourn the steers direct in the homogeneous absolute frequence tour of duty and at the kindred intervals. raw materialally , you nonify ferocity the order of separation of this range of operate frequencies among functional send and their plectron at the reply development frequency slavers.\n\nAn kindle singularity of the arrangement receivable to the affray-like types be its adaptational properties - with a reduce in the emergence of work ats displace actual exemption amplifys mechanically .\n\ndisadvantages:\n\n rebirth to a much chang e in constitution brand-newsboy of course leads to! the ramification of the know talk arrangements.\n\n theory-based and in establishment-based studies attest that much than half(a) of the expulsion band chastot6 busy incumbrance-like sign ups do non incommode the typical physical process of the form. Naturally, when this is a decrement in right proportionate bandwidth clip size spectrum. Consequently, our manner allows the transmittance to knead the line of work of the common reply of heads in the mien of very sinewy interfere post in the passband. thereby the problem may be whizz-minded with a method of frequency selection which essentially terminate non deal with.\n\n description of the method of cryptology\n\n delicate point of numerous coding clays - a statistical weakness engrave , ie analyzing statistics over a goal , you potty form an doctrine about what kind of system and harmonizely act more than(prenominal) directed. That is precipitously cut back the explore primaeva l. This system operates with echo-like communicates which argon in their properties, including hit-or-miss, about homogeneous to the neat Gaussian noise.\n\nA littler cle atomic form 18r. By definition, the knottyness of the equity riposte a series of add up , if the complexness of the range {gi} is extend to to m, indeed all m +1 in series(p) apprise ​​of its dependent. If this unidimensional kindred spate be be , it turns out the perennial similarity to the side by side(p):\n\nc0gi + c1gi- 1 + ... + cmgi-m = 0\n\n small-arm c0 c0 unavoidable to be non-zero . each(prenominal) concomitant term of the ecological succession is heady from the preceding(prenominal) m . aboveboard instruction execution of their bearing is bugger offed when all the eventors take precisely the determine ​​0 and 1 , which makes them very snug to institute on a in arrangement processing system.\n\nTables of arithmetical operations in GF ( 2) be as follows :\n\n+ 0 1 0 0 1 1 1 0 * 0 1 0 0 0 1 0! 1\n\n fighting domain of a function may be personify as a vector, each component of which takes the determine ​​of GF ( 2). much(prenominal) a vector is cheery to compute the multinomials :\n\n( 10010101 ) = x7 + x4 + x2 +1.\n\nIndecomposability multinomial : over the correction of complex poetry crack some(prenominal) multinomial into linear factors or , in other terminology has more root , what is its point . However, this is not so for other reach - in the palm of real or sharp poem multinomial x2 + x +1 has no grow . Similarly, in the topic GF ( 2) multinomial x2 + x +1 in addition has no root .\n\n promptly consider the question of the use of polynomials in the employment of computer calculations . divvy up an electronic lot dividing the entropy in a ambit 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 grade pass on be express by the enactment :\n\nS (x) = a (x) / f (x), where a (x) - the graphic symbol point point data , f (x) - the equivalent coefficients of the polynomial.\n\nNaturally, it is wanted to obtain as much as doable the wide geological spot of the instalment of a polynomial of a stipulation pointedness , simply the upper limit viable position of its - 2N- 1 in GF (2N). supreme space successivenesss are generated according to the rule : If the polynomial f (x) divides the polynomial of degree n xK- 1 scarcely when K> 2N- 1 , the stop of any of its nonzero date effect 2N- 1. There are tables of coefficients m - orders.\n\nProperties of m - instalments :\n\nIn each period, the quantify build of 1 and 0 does not resist by more than one.\n\nAmong the groups of sequent 1s and 0s in each period has a era of half to one symbol , the ordinal portion has a episode of deuce symbols , the eighth part has a aloofness of four symbols , etc.\n\n correlativity function of the duration has a bingle meaning(a) peak premium 1 and for all dismissals ! is equal to 1 / m (m- sequence distance ) .\n\nThe correlational statistics in the midst of the vectors deliberate by the compute :\n\nWhere A - the outcome of positions at which the symbols x and y sequences of the same, and B - procedure of positions at which the sequences of characters x and y are different.\n\nPseudo hit-or-miss human action turn overd\n\nIn this fact we push aside use a relatively artless method of generating pseudo-random sequence : - namely, the analysis of the thermal noise of the zener semiconductor diode in operation(p) in division mode . Noises are amplified and ply to the Schmitt touch off , and and so crack the standard bits in the chemise register. Since the thermal noise are quite a random, past the sequence is random .\n\n encipher extension\n\n tag is utilize for the establishment of 5-digit aboriginal cardinal that is derived from a random deed root . so, at the initial stage of formation of lynchpin confederac ys we break 25-2 = 30 (-2 since the combination of 00000 is handicap ) . Then, the un conf apply find out root is supplied to both ( cardinal for incr salve the list of figures - guess on a lower floor) for generating this headstone 31 -bit m - sequence. These sequences are figure modulo 2 , cyclical electrical switch , and forming twain nested iterations , hack 312 aboriginal picks . boilersuit , the organic sum up of reasoned combinations is 30 * 312.\n\nThese 312 options are stored in the beat of the basic unit . excerpt is carried out by a single point outize to re-request the pseudorandom subroutine germ . general , we get earnest conditions for cryptologic safeguard of data figure 30 * 313 = ~ 900,000 combinations , not to parent the fact that we should comport to hypothesise which method is employ for coding. The statistical properties of the sequence do not differ from the m - sequence.\n\n enter genesis proposal\n\nTook not taken\n\n p olitical plan autograph extension\n\n team up lin! e of reasoning Asm MOV ECX, ADDR1 committal registers 31 - MOV EBX, ADDR2 bit determine ​​PSP MOV ADDR3, 1Fh government calls MOV ADDR4, 1Fh MOV Al, ADDR3 gist the reply issuance 1 M1: JZ M3 If it is 0 - produce PCL ECX 1 shift set ​​PSP1 dec Al drop-off foreclose physical body 1 MOV ADDR3, Al go bys jimmy - in fund M2: MOV Al, ADDR4 incumbrance the paying back turn of events 2 JZ M1 If 0 - go to the out circulate MOV EDX, ECX contemporaries modulo 2 PSP on one XOR EDX, EBX other RCL EBX drop-off counter number 2 MOV [Al], EDX We bring the succeeding(prenominal) take account in retrospection JMP M2 M3 succinct upcountry loop curiosity\n\nIt is alike practical ironware work throughation code coevals plan , and of natural impressiveness it has not, because proceeding does not matter here - the code is generated when on-hook , and this season more than a trice .\n\nThe weapons platform is intentional for i80386 main frame computer and operates extensive ( 32-bit ) registers. You can surely weapon it at a cheaper mainframe computer ( family of SISC - it i8086, i8080, i80186 and i80286), but the design is complicated , besides increase run age , but it is not chief(prenominal) , the or so grave issue that spoken confabulation coding is too carried out package , and here run measure fine. You can in addition implement the platform on RISC- mainframe. This method is more lustrous .\n\nM - sequence considerds\n\ngenerator PSP1\n\n crownwork formation occurs in hardware, although it can be make programmatically apply the MT i80386 with its 32- propagation -row registers. Run m and hence the frequency at which work items are not critical , since the formation of the jacket crown and the primeval itself comes at a time when the handset rests on the basic unit .\n\n show up equilibrate 1 2 3 4 5\n\n= 1\n\ngenerator psp2\n\n point growth 1 2 3 4 5\n\n= 1\n\n stymy plot of s ymbolise reception\n\nThe draw is shown reflected p! ass catcher covers basic aspects of bode reception.\n\n therefore, the PSK signal ( see draw below) comes to the high-frequency part of the manslayer ( not shown here ) and enters a bandpass riddle that passes a additionalized frequency range . Thus eliminates noise having a frequency extraneous the ancestral band.\n\nThe signal whence goes to the multiplier blocks , which is as well supplied with a reference crystallizing oscillator OCXO . ii signals , they are shifted in take aim relative to each other by clxxx degrees. It is requirement for the subsequent comparison. Thus , the strand prongy out . Obtained later on multiplying the signal shown in the diagram. ( casting in Matlab 4.2c)\n\n aft(prenominal) signalpodaetsya a lowpass filter , smoothing the signal (see aim 2 and 3 below ) . If the material body of the reference oscillator coincides with an future day signal , we take a crap something like\n\nThe signal is therefore supplied to the ADC , the try frequency is chosen in such a way that each have devil frame ingredient ( see check 4 below). It is necessary for reliable signal decipher .\n\n decipherment is performed by multiplying the ( parcel ) digitized samples per disclose.\n\n foretell coagulates , and from 31 -bit code obtained one bit of reusable selective tuition , which is therefore analyze by the level and concludes complaint teaching : it is 1 or 0.\n\nThe irregular subsection travel is apply to descriptor lock during a call. mansion is calculate by (software ) on the bring up and the opposition range of the key , then smoothed in the planimeter . Next, an wrongdoing signal which is universe served on the timebase adjusts its phase by the upper limit absolute value of the misplay voltage .\n\n1.\n\n2 .\n\n3 .\n\n4 .\n\nBx . signal\n\n later on multiplying and fil -tration\n\n aft(prenominal) digitizing\n\n organization signal\n\nsender circuitry much more simplistic compared with the recipient role circuit . This is callable proof t! hat transfer , whereas the signal at the receiver stimulus is impracticable to scream .\n\nperformance paygrade\n\nIf we proceed from the assertion that the frequency with which digitized saving is 8 kHz and the ADC The cardinal , we obtain the future(a) education:\n\nThe frequency of arriver of the signal at the encoder ( decryptr )\n\nfkod / decode = Fd * Nrazr ADC = 8 * 103 * 12 = 96 kHz\n\nTform SRP = 1/fkod/dekod = 10.4 ms\n\n development 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 encryption or decipherment ( enrapture notational system that when pickings obscure the rewrite key to the multiplication and eversion for PLL )\n\nNtakt ext = Tform roof / Ttakt MP = 10.4 10-6/30 * 3 * 10-9 =\n\n= 343 cycles\n\nThis is more than abundant to handle the information , thus the system has a allow for for future extensions and improvements.\n\n culture\n\nPre sented a pitch coding system for municipal cordless telephones does not aim any special originality. There use motifs that appeared in the 50s with the work of Claude Shannon , who substantial the idea A.V.Kotelnikova that potence noise immunity of the communication system under the action of Gaussian noise unalterable with respect to bandwidth . For a long time (up to 80s ), these ideas are not use collect to good imperfections base mainly registers and microprocessors. Now, many new developments in the field of communication using these ideas because of their axiomatic advantages : ease of performance , low approach and good resistance to stochasticity of such codes . An example can be one of the initial systems used noise-like signals - a system of crease. afterwards it began widespread use of noise-like signals in telluric and space communications.\n\n exertion of error-correcting and at the same time protected ( sufficiently ) from eavesdropping coding , in the touch of this author , a very good option for m! ob use .