This is a proposal for a small uplink (ground to balloon) radio system:
Although the N0QBH decoder does not use DSP techniques the expected preformance should be quite good given the channel is running over FM.
Prototype system built on fibregalss matrixboard 60 x 26 x 12mm - weight 20g (including receiver module).
Good quality: Aim for sensitivity of -120dBm (0.22uV into 50ohm) for 12dB SINAD (signal + noise to noise ratio) and a 6db bandwidth selectivity of 10Khz (-/+5Khz).