getting troubles in ASK demodulator design

[logintojalluri]

hi
i am getting ASK modulated output as shown in attached figure.osc1_ch1 is primary coil side. OSC1_ch2 is secondary coil side. i am using the circuit as in attached one. but it gives 50mv. but i need 5V. plz any body give me guidance how to fix R and C values in envelop detector for ASK demodulation. and also need effective ASK demodulator circuit. I am using 1Mbps data rate and 13.56Mhz carrier frquency.
from
sharmi

 

[Darktrax]

My first thought is that the low pass filter to remove the RF component is about the most simplistic.
Before we go there..
How many amplitude levels are used in this ASK modulation?
You mention primary coil ans secondary coil. Where exactly is the transformer in the circuit?

There are many types of detector that would work fine to extract this amplitude waveform. If those really are volts units on the Y-axis of your waveform diagram, then even a basic diode detector would do better.

Please say what R and C values give you 50mV. If the R is high enough, you might get very little, and why use a lossy RC filter anyway?

You also need to mention what load the output is connecting to. The circuit will not drive a low impedance load. A decent demodulator would have an output driver.

So sorry, but what we have is insufficient, and confuses me also.

 

[FvM]

The waveform descriptions are apparently referring to previous threads
https://www.edaboard.com/threads/295254/
https://www.edaboard.com/threads/295387/

Apart from the many unclear points in your post, the circuit is at best forming an envelope detector, but it's missing the decision circuit required for an ASK demodulator.

If the modulation index is as low as shown in the waveforms (due to high Q resonant circuits in your mopdulator, if I remember right), demodulation will be difficult, but still feasible.

 

[logintojalluri]

I am attaching the circuit used for data transmission and corresponding output graph in tina software and L1=5.48u, L2=1u and M=351n and i have to generate minimum 5v

 

[logintojalluri]

nybody plz give some guidance