160 likes | 371 Views
Senior Design Project: Voice Activated Speed Dial. By: Xenia Prionas & Bob Siller. Introduction. Project divided into two parts: Phone line interface Hardware component DSP / Voice recognition Software component. Block Diagram. Three Major Components:. State Indicator Circuit
E N D
Senior Design Project:Voice Activated Speed Dial By: Xenia Prionas & Bob Siller
Introduction • Project divided into two parts: • Phone line interface • Hardware component • DSP / Voice recognition • Software component
Three Major Components: • State Indicator Circuit • DSP Input Interface Circuit • Tone Generator Control Circuit
State Indicator Circuit • Purpose: • To detect when phone has been lifted off the hook • To interface with the DSP board • On Hook: voltage output = 0 volts • Off Hook: voltage output = 5 volts
Specification Test • Does on-hook telephone leakage current exceed the phone company specifications? • Procedure: • Hook up a 1 M resistor in series with tip • Measure the voltage across resistor • Calculate the current across resistor I=V/R • Current must not exceed 2.5 A
Specification Test Setup Tip (+) Indicator Circuit Ring (-)
DSP Input Interface Circuit • Purpose: • To provide a voice signal for the DSP board to process • To provide the correct voltage specifications for the DSP board • 2 volts peak to peak • 0 DC component in signal
DSP Input Interface Circuit Provides voltage isolation Removes DC component from signal Attenuates input signal Voice signal from phone inputted here ThruCable to DSP Board Isolation Transformer
Tone Generator Control Circuit • Purpose: • To provide a means for the DSP board to dial a number • To automate the dialing process for the user
Tone Generator Control Circuit • Consists of 3 devices: • Op-amp • Electromagnetic relay • DTMF tone generator chip
Combination ofrow and column inputs Outputs a dual frequency onto thetelephone line Prevents replicationof tone by human voice DTMF Tone Generation
Tone Generator Control Circuit • Operation: • DSP board outputs a 2.2 volt signal • Signal goes into op-amp which amplifies the voltage to 12.54 volts - gain of 5.7 • 12.54 volt signal actuates electromagnetic relay • Relay connects the row and column DTMF tone generator inputs • Output DTMF tone is produced
Tone Generator Control Circuit Switch connects R1 and C1 producing a tone 12.54 volts output 2.2 volts output R1 C1 DSP Board KS58006 DTMF Tone Generator Vo = Vin (1+ R1/R2) Relay actuates
The voice activated speed dial project: Gave us experience in integrating several aspects of EE into a real world application Research, design and implementation of electrical components Conclusion • Telephone operation • DSP/Voice recognition • Teamwork