The EAGLE-65 is a PC plug-in board that forms the heart of a digital radio receiver. By using the RF front end of an existing radio receiver maximum pre-selection and dynamic range are obtained. The 455 kHz Intermediate Frequency (IF) output on your short-ware receiver connects to the IF signal input on the EAGLE-65 board.
This EAGLE-65 board sub-samples the 455 kHz IF signal (in phase quadrature) and the DSP filters separately the individual IQ components of the IF signal and detects the audio signal using a linear detector. The main DSP filtering is performed on the I and Q components of the IF signal NOT on the detected audio signal!
A powerful 32-bit 180 MFLOPs floating-point DSP (Analog Devices SHARC ADSP-21065L) allows precision FIR filtering of the IF signal with a 100 dB min filter stopband and linear detection ensures minimal Inter-Modulation Distortion. Filtering at the IF ensures minimal breakthrough from adjacent channels with no inter-modulation distortion products from the linear detector. Addition filtering by an adaptive-filter attenuates extraneous background noise, to further improve the clarity of reception.
Quadrature Sampling (IQ Sampling) maintains the phase integrity of the sub-sampled IF signal during DSP processing. Decimation reduces the sub-sampled input samples to a more useable audio sample rate, where the FIR filtering and detection of the IF signal takes place. The only analog section is to bandpass filter the 455 kHz IF signal before the A/D and the level setting amplifiers after the D/A.
The EAGLE-65 board plugs into a spare ISA slot of your PC. The application software runs under Windows 95/98 allows complete control of the IF Filtering and Demodulation modes.
Key Features:
DSP Detection modes:
DSP Filtering modes:
|
Please contact TRIONYX for further information and advice. |