Re: telemetry circuit design help requested
If I have understood your requirement correctly....
Have you thought of using an FPGA to do this work?
If yes, you may explore Xilinx 7 series FPGAs, where it is possible to embed soft processor core/s and develop custom logic around it (e.g. - connecting a peripheral hardware from which you can stream in the data) within a single die.
There you will have the possibility of programming either a MicroBlaze or ARM Cortex (depending on the FPGA development board) which have sufficiently large Block-RAM memories as the Inst. and Data memories.
If you want to explore the FPGA path, then please post further questions in the 'PLD, SPLD, GAL, CPLD, FPGA Design' section. This is the ASIC section.