Vocoder      

             A Vocoder Is AN Analysis/Synthesis System, Wont To Reproduce Human Speech. Within The Encoder, The Input Is Undergone A Multiband Filter, Every Band Is An Envelope Follower, And Therefore The Management Signals From The Envelope Followers Ar Communicated To The Decoder. The Decoder Applies These (Amplitude) Management signals To Corresponding Filters Within The Synthesizer. Since The Management Signals Amendment Solely Slowly Compared To The First Speech Wave Shape, The Information Measure Needed To Transmit Speech Will Be Reduced. This Enables Additional Speech Channels To Share A Radio Circuit Or Submarine Cable. By Cryptography The management Signals, Voice Transmission Will Be Secured Against Interception.

             The Vocoder Was Originally Developed As A Speech Computer User For Telecommunications Applications Within The nineteen Thirties, The Thought Being To Code Speech For Transmission. Sending The Parameters Of A Speech Model rather Than A Digitized Illustration Of The Speech Wave Form Saves Information Measure Within The communication Channel; The Parameters Of The Model Modification Comparatively Slowly, Compared To The Changes within The Speech Wave Form That They Describe. Its Primary Use During This Fashion Is For Secure Radio Communication, Wherever Voice Should Be Encrypted And So Transmitted. The Advantage Of This Technique Of "Encryption" Is That No 'Signal' Is Distributed, However Rather Envelopes Of The Band pass Filters. The Receiving Unit must Be Came Upon Within The Same Channel Configuration To Resynthesize A Version Of The Initial Signal Spectrum. The Vocoder As Each Hardware Associate Degreed Package Has Conjointly Been Used Extensively As An Electronic device.

           Whereas The Vocoder Analyzes Speech, Transforms It Into Electronically Transmitted Data, And Recreates It, The Voder (From Voice In Operation Demonstrator) Generates Synthesized Speech By Means That Of A Console With Fifteen Touch-Sensitive Keys And A Pedal, Primarily Consisting Of The "Second Half" Of The Vocoder, However With Manual Filter Controls, Needing A Extremely Trained Operator.