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  New blog post: Tianwen-1 safe mode telemetry. Peter from AMSAT-DL noticed that a few days ago Tianwen-1 was transmitting in safe mode. Here I analyze the telemetry signal, which is only 32 baud (16 bits per second). https://destevez.net/2026/08/tianwen-1-safe-mode-telemetry/

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  Muon Space is looking for an FPGA engineer for RF signal processing. Join a team of FPGA engineers and RF DSP engineers including myself to build state of the art RF instruments. Ability to access ITAR/EAR information required. DM me if you are interested or have questions. Here is the full job description: https://job-boards.greenhouse.io/muonspace/jobs/5187874007

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  New blog post: Getting peak TOPS on a Ryzen AI 7 350 NPU. This is an introduction to low-level programming on AMD NPUs using mlir-aie. I build an example that demonstrates 56 TOPS, very close to the max theoretical performance. These NPUs are identical to Xilinx AIE-MLv2 engines.

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  More fun with the Ryzen AI NPU. I'm working on a more complex algorithm, and I'm seeing memory stalls that make me lose one cycle in each iteration. It turns out that the data memory of compute tiles is organized as 8x 256-bit wide 8 KiB memory banks. Each bank supports one simultaneous access, and every two banks are interleaved to form a 512-bit wide 16 KiB virtual bank. The two load units of the processor can perform simultaneous 512-bit loads only if these target different 16...

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  Following up on yesterday's announcement by AMSAT-DL about the lack of signals received from Tianwen-1 since 2025-12-23, I have published a short post that contains the orbital state based on telemetry received up to 2025-12-22. This data shows that a reentry hasn't happened, unless there was a maneuver after the last telemetry we received. Read more: https://destevez.net/2026/03/where-is-tianwen-1/

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  Yesterday AMSAT-DL received and decoded again telemetry from Tianwen-1. I have done an updated plot of the orbital parameters with the new state vector telemetry. This shows that there have been no manoeuvres during the 3 months in which we haven't seen any signals. Read more: https://destevez.net/2026/03/tianwen-1-received-again-by-amsat-dl/

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  New blog post: Tooling for CSP. CSP is the cubesat space protocol. It is a network protocol used in cubesat buses, RF communications, and groundstations. Here I showcase some tooling to perform CSP network performance analysis and debugging that I have open sourced. There is a tool called csp-iperf that does throughput testing by using CSP ping packets, and a csp-ping-server that can be used in combination with that tool to reply to these packets.

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  New blog post: NB-IoT downlink. This is another post in my series about V16 car warning beacons. Here I explain mostly everything about the LTE NB-IoT downlink. It's perhaps the longest post I've ever written. If you want to know more about NB-IoT this is the place to go.

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  New blog post: Not-LoRa GRCon24 CTF challenge. This year I contributed a challenge track to the @gnuradio CTF. The idea of this challenge was to decode some analog voice signals that had been chirp spread using the same chirp parameters as common LoRa configurations.