Specific Design Approaches • Implement the shortest possible path for all communications. • Utilize HP3, RM, and LC series Linx modules for separate wireless links. • Employ a Motorola 68HC12 to provide user selectable frequency selection of the HP3’s. • Provide a wireless link between serial ports of the microprocessors to allow data communication.
Issues and Solutions • Interference and noise in wireless links. • Implement more direct communication (no retransmission of information). • Headset to headset – intercom, base station to base station – call feature, base station to headset – channel selection and additional features. • Difficulty employing digital technology. • Design all audio circuits for high quality analog communications. • Synchronous serial communication required for HP3 channel selection. • Utilize a synchronizer and combinational logic to recreate the clock pulse.
CommunicationTeam Micah Wu Daniel Anderson Nathaniel Anderson
Pending Tasks • Try to further eliminate noise using filters and adjusting channel frequency separation. • Consider power requirements and choose power supplies. • Implement the optimum antenna design for each wireless link. • Construct circuit components. • Interface with the other team’s components.
Block Diagram Base Station Headset Data Receiver From Audio Input From HC11 Serial Output To Serial Input Logic Audio/Data Receiver To HC 11 Serial Input Audio/Data Switch To Headphone Mixer Audio In Audio Out Data Transmitter From HC 11 Serial Output Audio/Data Transmitter Audio Transmitter Audio Receiver
Individual Responsibilities • Micah Wu • Antenna Design • Hardware Assembly • Daniel Anderson • Power Supply Selection • Hardware Assembly • Nathaniel Anderson • Filter Design • Hardware Assembly
Audio Team William Peacock Chris Barber Omar Saleem
Pending Tasks VOX/PTT Finalize the design and build the system that activates the transmitter and deactivates the receiver using the low power option on the HP3 modules. The VOX system rectifies the output of the microphone pre-amp and closes a relay to complete the HP3’s power down circuit. The push button directly completes the circuit. Noise Reduction Finalize the design of an audio mixer and second microphone system to block unwanted background noise. Amplifiers Finalize the design of the low-noise microphone pre-amps and power headphone amplifiers
Block Diagram Audio Out Intercom In Audio In Microphone Pre-amp Mixer Mixer VOX /PTT Microphone Pre-amp Headphone Amplifier Headset
Individual Responsibilities • William Peacock • VOX/PTT Completion • Hardware Assembly • Chris Barber • Audio Amplifier Completion • Hardware Assembly • Omar Saleem • Noise Reduction Completion • Hardware Assembly
Microprocessor Control Rajpartap Khangura Clint Kelley
Pending Tasks • Implement the wireless serial data transmission for the call functions. • Design the synchronizer circuit to allow the asynchronous HC12 serial port to change channels on the HP3 modules. • Assist the other groups in implementing their components.
Block Diagram Audio/Data Transmitter Audio/Data Receiver Microprocessor Serial Port 0 Tx Keypad/LCD Display Synchronizer Serial Port 1 Tx Serial Port 1 Rx CS1 on HP3 CS2 on HP3 To data transmitter From data receiver
Individual Responsibilities • Rajpartap Khangura • Complete the call system. • Assist the communication team. • Clint Kelley • Design the synchronizer and implement the channel selection function. • Assist the audio team.
Week 1 Week 2 Week 3 Timeline Antenna Design Communication Team Build communication components Assemble Intercom Test and implement Audio and Data Transceiver Amplifier and VOX/PTT Completion Assemble Intercom Audio Team Build and test headset Noise Reduction and Mixer Completion Channel and Keypad Program Integrate Program Assemble Intercom Microprocessor Team Assist Other Groups Call Program Integrate Program
Conclusion • Each block of the project is near the end of the design phase. • Circuit assembly of all components will be complete by November 10. • Working prototype will be completed by November 15.