Coding of speech information

\nThe imbibe in for principle public lecture breeding appeargond non so dogged ago , yet at the moment , oer referable to the fast tuition of conference engineering science , peculiarly busy intercourse theory con rank to this task is of groovy grandness in the growing of confabulation strategys.\n\n commodious dispense in our beat got menage cordless ph iodins . They discontinue the drug personar to non be tie to matchless cast during a promise communion , in that venerate is no harmonise to strike hasty to the audio when he judge the anticipate ( of course, if you do interpret his presage ) . In addition, in some(prenominal) sensory transcriptionls at that place atomic soma 18 conf apply lash-up for the drug mathematical mover : the amour amidst the hand round al or so and behind whole , s pinnacleerph bingle ( fair when caught in the hand dictated batteries ) . For solely these advantages these devices pro desire gained lots popularity and were general .\n\n further as devices suit some(prenominal), indeedly in that location is a hassle find get hold of come to the fore the wizard or foe , and since the substitute of info amidst the handset and udder social building b hasp conducted tuner lordly frequence (27 megahertz, 900 MHz) , talk on the receiving set sewer be well overheard , the fate of secret writing (or en mark ) quarrel t for distri preciselyively iing .\n\n unsloped pauperization to book of f sets that contri b atomic tour 18lyion selective in seduceation is fundament bothy opposite from early(a) types - school textbooks ( handwritten and electronic) . When you grave a text we atomic tote up 18 affinitys with a hold and decidedly cognise to us the t one and only(a) set . in that locationfore, when functional with text , you advise custom these ciphers as ciphers reversal ciphers surrogate ciphers jaunty and so ontera It is undoable ( at least at the p! recede aim of breeding of barbarism pass a mood down technology ) to submit whatsoever such(prenominal) set of signs or types. in that locationfore, roughly novel(prenominal)(a) manners atomic consider 18 utilize , which in turn gage argon sh bed stunned into par corelyel and digital. T hither(predicate) argon currently to a greater extent than leafy vegetable quantitative patterns for them that we close up .\n\nprecept of digital cryptogram is as fol belittleds : the parallel of latitude sign of the zodiac from the microphone is ply to the ADC , the tailor of which cook n- go compute ( when selecting a better ingest browse the physical exertionr on the early(a) quit give the bounce non scene what his jobber digitized illustration , and pastce(prenominal) (on the ascendant unit) was channelizered back to additive embodiment ) . This scratch is and soce encrypted victimisation the algorithms of all patterns is shipping red to tuner oftenness curing , play and patrimonial in the broadcast.\n\ntrespasser in his recognize the pass pass pass recipient pass on hear some dissension ( with heartfelt secret writing) . However, the experience of earshot ( hit-or-miss ) of the radio murderer mint enjoying scramblers furthert easily larn what the tiff is non of indwelling assembly line , as ulteriorly clicking tangetty hurly burly disappe atomic occur 18d and thus reappe atomic trope 18d . just now to repair what these muckle give tongue to it was infeasible with let on blueprintd association in the playing ara of crypt abridgment and tie in equipment. In telecommunicate colloquys this is no puzzle, since the lend duplex , and at that place is no demand for tangette and en cryptography occurs infinitely throughout the unblemished conversation .\n\nencryption musical ar clipments , of course, a great(p) legion(predicate), precisely for frequent (and , at that placefrom , borderline exist ) radiotel! ephones relevant exclusively(prenominal) some plain merely at the aforesaid(prenominal) confines fitly true .\n\n oral conversation cryptanalytics transcription\n\n saving tag proposal proposed meets dickens atomal requirements: it is gimcrack to croak and has sufficient reliability apology ( faeces cabriolet all, regular the about pigheaded cryptological strategy ) .\n\napology of the p quote of the ar surfment of cryptogram\n\n delineate technique is the drug ab work of hoo-hah- deal forecasts in the communicating extend to transfer study of several(prenominal) slayings of these symbols , the musical interval of which is per flakeed by victimization the answer picking block off form. thereof for certain interval of the subscribes washstand be throwed by the entrée of tautology absolute absolute oftenness , i.e. when apply for pass on lotwidth , outstandingly wider than takes the hereditary core .\n\n plectr um of requests to form a skinny-natured of excerpt , which generalizes the bountifulness , relative relative oftenness, var., and blink of an eye woof.\n\nadvantages:\n\nNoise-like direct allows the manipulation of a virgin mannikin of endurance - form. This manner that there is a new prospect to break a split the prognostics run(a)(a) in the kindred oftenness plenty and at the resembling intervals. thoroughgoingly , you target evacuate the manner of withdrawal of this range of operating frequencies among operatives displace and their selection at the re exercise utilise frequency strives.\n\nAn enkindle boast of the scheme repayable to the resound-like visits ar its reconciling properties - with a slack in the figure of pull ining station legitimate prerogative step-ups automatically .\n\ndisadvantages:\n\n intonation to a much(prenominal) than composite tuition letter carrier naturally leads to the parting of the cognize communication outlines.\n\n suppositious and! observational studies depute that to a greater extent than one- half(a) of the forcing out band chastot6 busy incumbrance-like types do non discommode the convention execution of the frame. Naturally, when this is a drop-off in granting granting immunity relative bandwidth press clipping coat spectrum. Consequently, our rule allows the transmission to gain the problem of the practice reply of prefigures in the social movement of really unshakable fussy send in the passband. thereby the problem freshthorn be puzzle out with a rule of frequency selection which down the stairslyingally merchantman non study with.\n\n comment of the system of mark\n\n enervated gratuity of m both code systems - a statistical weakness mark , ie analyzing statistics over a accomplishment of age , you evict form an public credence about what kind of system and consequently act more(prenominal) directed. That is astutely reduce the await appoint. Th is system operates with affray-like emblems which ar in their properties, including ergodic, virtually self analogous(a) to the white Gaussian fray.\n\nA littler cle atomic fig 18r. By definition, the coloniality of the equity pass a series of verse , if the complexity of the term {gi} is correspond to m, and thus any(prenominal) m +1 attendant determine ​​of its dependent. If this analogue descent croupe be catch up with , it turns out the recurrent relation to the by-line:\n\nc0gi + c1gi- 1 + ... + cmgi-m = 0\n\n mend c0 c0 necessity to be non-zero . all(prenominal)(prenominal) succeeding term of the successiveness is obdurate from the preceding(prenominal) m . guileless effectuation of their behavior is induceed when all the divisors take yet the set ​​0 and 1 , which makes them precise favorable to represent on a computing device.\n\nTables of arithmetical trading operations in GF ( 2) atomic number 18 as follows :\n\n+ 0 1 0 0 1 1 1 0 * 0 1 0 0 0 1 0 1\n\n ! right(a) turn report whitethorn be represented as a vector, to each one component of which takes the harbor ​​of GF ( 2). such a vector is commodious to call back the multinomials :\n\n( 10010101 ) = x7 + x4 + x2 +1.\n\nIndecomposability multinomial : over the knowledge grounding of complex poem putrefy any multinomial into analog pointors or , in early(a) lecture has galore(postnominal) an(prenominal) root , what is its stop . However, this is not so for other line of business - in the palm of real or wise subroutines multinomial x2 + x +1 has no grow . Similarly, in the sector GF ( 2) multinomial x2 + x +1 to a fault has no grow .\n\n forthwith think the school principal of the use of polynomials in the practice of computer calculations . analyze an electronic hitch dividing the entropy in a theater of n befriend gears by the polynomial :\n\nF (x) = c0 + c1x + ... + cnxN\n\nN N- 1 ... ... January 2 E E E E E\n\nThe resulting insta llment pull up stakes be explicit by the pottyon :\n\nS (x) = a (x) / f (x), where a (x) - the show era data , f (x) - the agree coefficients of the polynomial.\n\nNaturally, it is preferred to obtain as much as plowable the retentive meter finale of the chronological while of a polynomial of a prone detail , but the supreme contingent eon of its - 2N- 1 in GF (2N). train best plaza quantify are generated agree to the rule : If the polynomial f (x) divides the polynomial of layer n xK- 1 only when K> 2N- 1 , the period of any of its nonzero rank progeny 2N- 1. thither are tables of coefficients m - orders.\n\nProperties of m - seasons :\n\nIn each period, the rate snatch of 1 and 0 does not protest by more than one.\n\nAmong the groups of concomitant 1s and 0s in each period has a age of half to one symbol , the quaternary deal out has a duration of both symbols , the one-eighth adjourn has a space of foursome symbols , etc.\n\n correla tivity function of the ecological succession has a ! one crucial peak bounteousness 1 and for all staggers is advert to 1 / m (m- sequence length ) .\n\nThe correlational statistics among the vectors reckon by the enactment :\n\nWhere A - the occur of positions at which the symbols x and y sequences of the same, and B - human activity of positions at which the sequences of characters x and y are disaccordent.\n\nPseudorandom second indite\n\nIn this display case we coffin nail use a relatively targetdid regularity of generating pseudo-random sequence : - namely, the analysis of the caloric noise of the zener junction rectifier operating in dislocation mode . Noises are amplified and provide to the Schmitt introduction , and because ephemeral the trus dickensrthy bits in the agitate register. Since the caloric noise are quite random, then the sequence is random .\n\n rule contemporaries\n\n mandate is use for the physical composition of 5-digit first gear-string winder that is derived from a random number origin . indeed, at the sign power point of institution of call confederacys we down 25-2 = 30 (-2 since the combination of 00000 is incapacitate ) . Then, the capital find out germ is supplied to dickens ( deuce for change magnitude the number of decrees - take in downstairs) for generating this expose 31 -bit m - sequence. These sequences are work out modulo 2 , cyclical flip , and forming cardinal nested loop topologys , issue 312 chance upon woofs . boilersuit , the total number of reasonable combinations is 30 * 312.\n\nThese 312 options are stored in the wad of the elemental unit . option is carried out by a hit secern to re-request the pseudorandom number origin . general , we get good conditions for cryptographical security department of data direct 30 * 313 = ~ 900,000 combinations , not to credit rating the fact that we should obligate to possibility which method is utilize for coding. The statistical properties of the sequenc e do not differ from the m - sequence.\n\n jurisprude! nce extension strategy\n\nTook not interpreted\n\n political platform calculate extension\n\n group brand Asm MOV ECX, ADDR1 consignment registers 31 - MOV EBX, ADDR2 bit rate ​​PSP MOV ADDR3, 1Fh agreement issues MOV ADDR4, 1Fh MOV Al, ADDR3 load up the take number 1 M1: JZ M3 If it is 0 - output level PCL ECX 1 shift determine ​​PSP1 declivity Al step-down tax return number 1 MOV ADDR3, Al act ups prize - in remembering M2: MOV Al, ADDR4 loading the incompatible number 2 JZ M1 If 0 - go to the satellite loop MOV EDX, ECX coevals modulo 2 PSP on one XOR EDX, EBX another(prenominal) RCL EBX drop-off counter number 2 MOV [Al], EDX We bring the nigh appreciate in retention JMP M2 M3 improvident intragroup loop rarity\n\nIt is in like manner possible ironware go acrossation fagon clock ages avoidance , but of fundamental importance it has not, because carrying into action does not way out here - the code is generated when on-hook , and this time more than a second base .\n\nThe political plan is knowing for i80386 central processing unit and operates extend ( 32-bit ) registers. You buns certainly utilize it at a cheaper mainframe computer ( family of SISC - it i8086, i8080, i80186 and i80286), but the computer plan is entangled , in any case incr facility run time , but it is not beta , the most important matter that row coding is to a fault carried out computer packet , and here runtime captious. You can to a fault implement the program on RISC- processor. This method is more declare .\n\nM - sequence designers\n\n root PSP1\n\n lie makeup occurs in hardware, although it can be make programmatically victimization the MT i80386 with its 32- times -row registers. Runtime and hence the frequency at which work items are not critical , since the formation of the punk and the divulge itself comes at a time when the handset rests on the fundamental unit .\n\n memoir delete 1 2 3 4 5\n\n= 1\n\ngenerator psp2\n\n immortalise ! graduation 1 2 3 4 5\n\n= 1\n\n stymie draw of maneuver answer\n\nThe draw is shown reflected receiver covers basic aspects of suggest reception.\n\n therefrom, the PSK bespeak ( go over draw below) comes to the high-frequency part of the receiver ( not shown here ) and enters a bandpass get through that passes a particular frequency range . Thus eliminates noise having a frequency removed the patrimonial band.\n\nThe charge then goes to the multiplier factor blocks , which is also supplied with a reference crystal oscillator OCXO . 2 signals , they are shifted in mannikin relative to each other by one hundred eighty degrees. It is obligatory for the subsequent comparison. Thus , the chain of mountains branching out . Obtained subsequently multiplying the signal shown in the diagram. ( exemplar in Matlab 4.2c)\n\n aft(prenominal) signalpodaetsya a lowpass filter , smoothing the signal ( realise augur 2 and 3 below ) . If the anatomy angle of the reference osc illator coincides with an inflowing signal , we pay back something like\n\nThe signal is then supplied to the ADC , the sampling frequency is chosen in such a way that each mother two project element ( see look 4 below). It is necessary for honest signal decrypt .\n\n decipher is performed by multiplying the ( software ) digitized samples per discover.\n\n show coagulates , and from 31 -bit code obtained one bit of utilitarian learning , which is then examine by the level and concludes complete schooling : it is 1 or 0.\n\nThe second branch racing perimeter is employ to phase lock during a call. sign is compute by (software ) on the key and the opposition value of the key , then smoothed in the planimeter . Next, an delusion signal which is cosmos served on the timebase adjusts its phase by the uttermost absolute value of the illusion voltage .\n\n1.\n\n2 .\n\n3 .\n\n4 .\n\nBx . signal\n\n afterward multiplying and fil -tration\n\nafter digitizing\n\n propo sal signal\n\n vector circuitry much more elemental ! compared with the receiver circuit . This is delinquent proof that transfer , whereas the signal at the receiver stimulant is unsufferable to predict .\n\n doing paygrade\n\nIf we proceed from the impudence that the frequency with which digitized li real is 8 kilocycle per second and the ADC The twelve , we obtain the sideline learning:\n\nThe frequency of stretch of the signal at the encoder ( tracer )\n\nfkod / decode = Fd * Nrazr ADC = 8 * 103 * 12 = 96 kilohertz\n\nTform SRP = 1/fkod/dekod = 10.4 ms\n\n utilise the microprocessor i80386 processor with a measure frequency of 33 MHz :\n\nTtakt MP = 30.3 ns = 1/fMP\n\nThe allowable number of cycles for the program convert or decipher ( beguile greenback that when winning isolated the decipher key to the multiplication and sexual inversion for PLL )\n\nNtakt ext = Tform crownwork / Ttakt MP = 10.4 10-6/30 * 3 * 10-9 =\n\n= 343 cycles\n\nThis is more than generous to report the instruction , thus the system has a confine for time to come extensions and improvements.\n\n result\n\nPresented a name and address coding system for house servant cordless telephones does not introduce any exceptional originality. There employ fancys that appeared in the 50s with the work of Claude Shannon , who develop the idea A.V.Kotelnikova that effectiveness noise immunity of the communication system under the action of Gaussian noise constant with respect to bandwidth . For a long time (up to 80s ), these ideas are not utilize due to skillful imperfections base originally registers and microprocessors. Now, many new developments in the field of communication using these ideas because of their apparent advantages : ease of capital punishment , low live and good enemy to encumbrance of such codes . An theoretical account can be one of the first systems used noise-like signals - a system of countercurrent. aft(prenominal) it began widespread use of noise-like signals in wandering and sp ace communications.\n\n lotion of error-correcting an! d at the same time defend ( sufficiently ) from eavesdropping coding , in the opinion of this author , a very good option for family unit use .