Presented by:
S,Mohan Tamizhmani & M.Manuel Jude Vinoth

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ABSTRACT
Cellular communication industry has grown leaps and bounds to become the essence of day to day science. Cell phone is the heart of cellular industry. The number of cell phone users is growing exponentially. But the privacy of user and security of cell phone remains a challenging question.
Stealing cell phone has become the eye catching business for culprits. There should be a reliable method of protecting the instrument from burglars. Our paper proposes a new innovative, reliable, fool proof security measure for cell phones using VOICE RECOGNITION.
Voice recognition is the identification of an individual identity using speech as the identifying characteristic. The voice of the user is processed (Speech Processing) using a digital signal processor which is the prime part of a cell phone. We are programming this DSP to implement this protection technique.
Firstly an original voice database of the user is created. This database is stored in the Flash ROM(8M) which is available inside the cell phone. Then whenever the user speaks through the cell phone part of the speech sample is taken and encoded. This processed voice of the user is compared with the original database to check the identity of the user. If the user is authorized, he is allowed to continue his talk. If not the transmission is cut abruptly by making the MP in idle state. Thus the cell phone is being protected from any unauthorized user. Even if the cell phone was stolen or missed it won’t be useful for any other person.
The programmability of DSP and universality of Voice based identification has given our method a dual advantage. Our proposal demands neither external hardware nor extra cost. The above method possess no hardship for the user unlike the present security systems. This method can be adopted universally in all models of Cell phones for protection.
INTRODUCTION
The word Cell Phone has become the greatest buzz word in the Cellular Communication Industry. The threat for cell phones is also increasing. Stealing a cell phone and selling them in black market has grown into a profiting business. Hence there arises a need to adopt a fool proof security system to prevent these unlawful activities, unauthorized usage and safeguard the user. Our paper tells about a new system of Cell phone protection using Voice Recognition.
VOICE RECOGNITION BY BIOMETRICS
Voice recognition is the identification or verification of an individual identity using speech as the identifying characteristic. There is no attempt in voice recognition to necessarily identify the content, or speech, of a sound-stream, merely to identify its auditory and vocal characteristics. An individual speech spectrum is of the form as shown here.
In this case the sound signal is digitized and then the digitized signal is compared to previously recorded samples held in a database. The result is a simple yes/no decision as to whether the speaker has been identified. A diagram of a typical voice recognition process is shown in Figure 1.
Voice biometrics works by digitizing a profile of a person's speech to produce a stored model voice print, rather like a template, which is referred to each time that person attempts to access secure data. Biometrics technology reduces each spoken word into segments: sub-word like syllables, phonemes, triphones or similar units of sound, composed of several dominant frequencies called formants, which remain relatively constant over that segment. Each segment has three or four dominant tones that can be captured in digital form and plotted on a table or spectrum.
When a person speaks his or her passphrase, the code word or words are extracted and compared to the stored model for that person. When a user attempts to gain access to protected data, their passphrase is compared to the previously stored voice model and all other voice prints stored in the database.
CELL PHONE ARCHITECTURE
The basic internal architecture cell phone mainly consists of the following parts.
 Kernel which is nothing but a microprocessor.
 Vocoder is a DSP (Digital Signal Processor).
 Memory (SRAM, Flash ROM & EEPROM)
 RF interface for transmitting and receiving of data.
 System clock (an oscillator producing frequency)