AB103-Demodulator

The AB103 is a software module for implementing FM demodulation on a fixed point TI DSPs.

The AB103 accepts IQ signal as input and generates a demodulated signal at output. It is designed to demodulate FM signals as presented by in-phase and quadrature components (IQ) of input signals.

The package also includes a Simulink model of the application for simulation and for translation to C code using PARS tools.

Full_system_hilbert_to_file_two_signal/FM Modulator

FM Demodulator output signals can be displayed using plot_output_file.m for visualizing demodulated signal and its frequency content.

Input signal and its frequency

The original, the demodulated signals, and their frequency content are shown in the following figures:

Demodulated signal and its frequency

The graphs for the demodulated signal are very similar to the graph of the original signal. The change is in its phase which is usually caused by delay in system and is independent of the frequency.

The 100Hz plus the 4KHz original and modulated signals on a 40MHz carrier signal are shown on the following figures:

Original signal

Demodulated signal

SPECIFICATIONS

• Fixed point DSP processing
• Variable number of IQ data channel per module
• Performance for 4 IQ channel using TMS320C6713 @ 300MHz

DELIVERABLES

• C source code and header ( .c, .h ) files
• C6000 object library ( .lib ) files
• 3L Diamond/DSP RTOS integration support ( .cfg ) with implementation examples
• Matlab simulation NOTE: Not available in Release 0.2
• User Guide