From HPSDRwiki
Revision as of 13:14, 14 February 2007 by WikiSysop (Talk | contribs)

Jump to: navigation, search

ODYSSEY - Low Power Handheld SDR

The Odyssey Project includes a low power SDR based on the QSD, QSE, and a dsPIC33 as the basic radio core. Odyssey will be more than an SDR and you may expect this page to be dynamic.

General Description:

The Odyssey Project was born at the Johnson Space Flight Center in Houston, Texas. AMSAT, ARISS are helping get ready for the SUITSAT-2 experiment. We believe there will be a SUITSAT-2 so effort is being spent on the design of interesting experiments for it. The design for the proposed SUITSAT-2 experimental package includes several neat features. The RF equipment is built around a standard QSD and QSE with the DSP to be done on a Microchip dsPIC33. Several integrated housekeeping unit functions are to be done on other Microchip PIC's. These include capture of CCD camera images and the conversion of these images to SSTV formats.

Project Designers

Joe Julicher, N9WXU
Steve Bible, N7HPR
Frank Brickle, AB2KT
Bob McGwier, N4HY
Lou McFadin, W5DID

Odyssey is the project name for the test hardware for an SDR based satellite. The first application will be Suitsat 2. We would like to produce test hardware that allows interested HPSDRer's to help test/evaluate/develope the suitsat flight hardware and ground station. Odyssey is a collection of boards.

The circuits on the individual boards below will be integrated into one PCB for flight early next year. But we need to develop the HW/SW and get some beta testing done so we can iron the bugs out. This is also a good prototype for very small SDR based repeaters, digipeaters, telemetry systems, etc. Lots of terrestrial applications.

Siren Revision A

Siren - dsPIC33 based SDR tx/rx with seperate 10.7MHz input/output for external mixer/amplifier. Below are the Revision A of Siren schematics and PCB layout. The current design is based upon the the SDR1000 which was quick an easy to produce for testing and initial DSP programming. Revision B (see below) will have the newer designs for higher performance.

Features are: dsPIC33 TLV320AIC23B Codec QSD QSE crystal sampling clock optional SMA input for sampling clock

Media:SDX Schematic.pdf Proto 1 schematics

Media:SDX PCB.pdf PCB Layout

Odyssey SDX Rev A 2006-11-06.jpg

Odyssey Siren Revision A is RUNNING as a 10.7 MHz full duplex IF at 48 kHz bandwidth! We have FreeRTOS running on the board. The Siren dsPIC33 is running at the full 40 MIPS rate. Expect much more soon (2/3/2007).

Siren Revision B

This revision B schematic contains Ahti's OH2RZ ISD circuit and Howard Long's G6LVB exciter circuit (see STELLA [1]. The codec has been changed to the TLV320AIC31. The goal of the circuit is to take advantage of the differential inputs and outputs of the codec. --N7HPR 09:15, 30 October 2006 (PST)

Media:Odyssey SDR Rev. B.pdf


Odysseus - PIC24 based unit that will encode the SSTV, encode packet (with FX-25), and play recorded voice to the Siren board. The actual Flight hardware includes Cyclops, Odysseus, and Siren for a single IHU (Integrated Housekeeping Unit) The schematics below are the first prototype for the complete IHU.

Sheet 1 : (Cyclops) Wiring the CPLD. The CPLD steers the image data from the image capture chip into the DRAM. It also provides a DRAM interface for the PIC24 microcontroller. The CPLD adds the luminance data from the video feed so the PIC24 can get an idea if a bright object is in view. Any bright object seen by the Satellite is likely to be something interesting.

Sheet 2 : (Cyclops) This is the Philips SAA7113H video capture chip. This chip produces a stream of digital data representing an NTSC or PAL video feed. The digital data is stored into the CPLD.

Sheet 3 : This sheet contains the analog power supplies. The Video capture device and the CPLD/DRAM can be turned off to save power and extend the mission time. The final IHU will have an external switching regulator so this sheet will change. The LED's are for debugging the power management software.

Sheet 4 : (Cyclops) DRAM and terminating resistors.

Sheet 5 : (Odysseus) PIC24FJ128GA010 and interfaces. This is the 16 mips PIC24 microcontroller. It has 128kbytes of Flash. This device will be encoding the images for SSTV transmission, reading stored messages from the Transflash card, and collecting data from user supplied experiments. This microcontroller will produce digital audio data that will be sent to the siren baseband processor (a dsPIC33) via an SPI data bus. The flight hardware will have the siren integrated into the IHU motherboard.

Sheet 6 : (Odysseus) This sheet has all the I/O for the transflash, the experiments and the serial debug port. It also has the prototype experiment power switch. The final power switch will be integrated into the external power supply. The experiment connector pinout will change. The current prototype shows the Rev 1 pinout. The Rev 2 pinout includes the video connections for the external cameras.

Schematics: Media:odysseus.pdf

Pictures IHU IHU PROTO 1.JPG Odysseus Portion ODDYSSEUS.JPG Cyclops Portion of the IHU Cyclops.JPG

Software modules required are: SSTV Encoding (Scotty 1, Scotty 2, Robot 36) 1200 Baud Modem (transmitt only) AX-25/FX-25 Software Stack SD-Card Interface Power Management Mission Scheduler Uplink demodulator (unknown protocol)


Cyclops - Video Capture for use by the Odysseus board.

Media:Odyssey Cyclops -ATLAS-.pdf

Media:Odyssey Cyclops -CPLD-.pdf

Media:Odyssey Cyclops -VIDEO-.pdf

Media:Odyssey Cyclops -POWER-.pdf

Media:Odyssey Cyclops -DRAM-.pdf

Media:Odyssey Cyclops -PCB-.pdf


Circe - mixer/amplifier for 2m tx and 70cm rx. This is the last piece for a complete satellite transponder. (Circe had a "split" personality)