Iris (transponder)

File:Iris-transponder.png

The Iris transponder is a small, low power deep-space transponder designed by JPL for use in cubesats.{{cite web |url=https://www.jpl.nasa.gov/cubesat/pdf/Brochure_IrisV2.1_201611-URS_Approved_CL16-5469.pdf |title=Iris V2.1 CubeSat Deep Space Transponder |year=2016 |publisher=JPL}}{{cite web |url=https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=3603&context=smallsat |title=Iris Deep Space Transponder for SLS EM-1 CubeSat Missions}} It unifies a number of communication functions - receiver, command detector, telemetry modulator, exciters, and control functions - into one 1.2-kg package that occupies about 0.5 U. Iris is designed to handle X band uplink, UHF receive, and both X band and optional Ka band downlink. It is only one third the mass, and lower power, compared to the smallest previous solution, the Small Deep Space Transponder.

==Functions==

The capabilities of Iris include:

• X-band receiver/downconverter capable of carrier tracking.
• Command detector unit function.
• Telemetry modulation function.
• X-band exciter.
• A matching X-band power amplifier and low-noise amplifier.
• X-band ranging.
• UHF (390-450 MHz) receiver for communication with landers/rovers.
• Differential one-way ranging (DOR) at X-band.
• Uplink: TC Space Data Link Protocol - CCSDS 232.0-B-3
• Downlink: AOS Space Data Link Protocol = CCSDS 732.0-B-3
• Supports codes Convolutional 7-1/2, Manchester, Bi-Phase, and bypass (NRZ), Reed Solomon (255,223), Turbo codes with rates 1/2, 1/3, and 1/6 (block size 8920 bits)
• Interface to rest of CubeSat electronics is through Serial Peripheral Interface Bus, with a special hardwired output to reset the CubeSat.