Need help in designing a transmitter and receiver.

[kanni]

hi..
i am currently making a project that looks like this...

[analog input]--->[ band limiting filter]--->[ PCM Encoder]--->[ASK modulator]--->[Wireless channel]--->[ASK
demodulator]--->[PCM Decoder]--->[Lowpass filter]--->[analog output]


is there any reflectance that i can use to build up this circuit??
im thinking of using PT 2262 and pt 2272as my encoder and decoder.

thanks..

[shahrul]

If using microcontroller, you can short into
[analog input] >> [UART] >> [Transmitter] ---- [Receiver] >> [UART] >> [analog output]
You can see example Transmit data through RF and then analog output.

[kanni]

If using microcontroller, you can short into
[analog input] >> [UART] >> [Transmitter] ---- [Receiver] >> [UART] >> [analog output]
You can see example Transmit data through RF and then analog output.

i have the transmitter and receiver circuit..what if i directly convert analog signal to digital signal then connect it with my transmitter.. will it work?? how to make the ADC converter and DAC converter. thanks

[shahrul]

i have the transmitter and receiver circuit..what if i directly convert analog signal to digital signal then connect it with my transmitter.. will it work??

Convert analog to digital. UART is digital signal.

how to make the ADC converter and DAC converter.

ADC is build-in in the PIC. DAC can build using R-2R ladder or convert PWM-to-analog.

[yonghui]

hi,
i think it will be better to use microcontrollers to do this task compared to PT 2262

as mentioned by Sharul, ADC in microcontroller is readily to be used for the analog to digital conversion, then the digital signal is transmitted as wireless after encoding using UART protocol. the ASK thing is done by the RF module already.
at receiver side, the demodulation of ASK is done by receiver module. the signal will be received and UART signal and decode by microcontroller.

in addition to Sharul's comment on using R2R resistor ladder as DAC, u can use the PWM module in microcontroller as the DAC to convert the digital data to analog values. the PWM pulse can be easily changed to analog voltage by simple RC filter of one resistor and one capacitor.


regards,
yh