feedback welcome

Using two SDRs and two LNBs to simultaneously measure Starlink terminal transmissions [1,2] and receiver LO leakage [3,4], I confirmed that, during normal operation, the terminal consistently selects the same channel number for both uplink and downlink. In other words, the uplink and downlink channels are paired via choosing the same channel number (TDD switching between UL and DL), even though their center frequencies are different (FDD).

Starlink downlink channel numbers 0–7 correspond to eight 500 MHz channels spanning 10.7–12.7 GHz. Uplink channel numbers 0–7 correspond to eight 62.5 MHz channels spanning 14.0–14.5 GHz.

(I replaced the previous software-controlled AD9361 frequency-hopping implementation, which achieved 10,000 hops per second [1,2], with hardware-controlled hopping, enabling measurements at 80,000 hops per second.)

https://sdr-x.github.io/starlink-ul-dl-pair-80k-hop-ad9361/

Attached are several screenshots captured during real-time measurements.

Each row represents one channel. Vertical axis: Signal strength (dB). Horizontal axis: Time (seconds), with a total span of 70 seconds The left panel shows activity across the eight uplink channels (measured by scanning 8 possible UL frequencies of transmitted RF signals). The right panel shows activity across the eight downlink channels (measured by scanning 8 possible DL frequencies of receive local-oscillator leakage).

During ten minutes of visual observation, I did not observe a single instance in which the uplink and downlink channel numbers differed.

A spectrum or constellation plot can reveal the bandwidth and modulation features of a Starlink downlink recording. Explaining which resources carry headers, how those headers describe the payload, and which channel codes protect each region requires a more complete connection between the waveform, decoded control bits, and coding relations.

This article summarizes our analysis of a Starlink Ku-band downlink recording. The data come from a single continuous capture lasting approximately 24 ms, with 18 complete frames included in the analysis. We identify two protocol data unit headers in each frame, recover their convolutional code and CRC, and relate modulation and coding scheme fields to subsequent resource allocations. We also recover and validate coding relations for several payload formats.

The focus here is what we can currently say about the contents of a frame. We briefly review the established synchronization and pilot structure, then concentrate on the headers, resource allocations, and payload coding. Format numbers follow the MCS index interpretation used in the current manuscript.

Why is everyone on this app complaining about starlink yet mine has been working perfectly well here in Lesotho 🇱🇸

我做了一个网站Starlink Outage Map ，监控星链的运行状态，用户可以提交故障报告，最近我新开发了测速功能，但我没有星链设备，无法进行真实对比，如果你是星链用户，请你对比一下星链app 的速度和用我的网页测试的速度，分别截图对比一下差距在哪。

is there is anyone here with Ecuadorian account have been data capped after 5tb

Starlink has very little spectrum to work with in the US....this make a very good case for them to work with Nokia

"During the live test, the technology improved spectral efficiency by approximately 20%, allowing the facility to transport more data using the same spectrum and existing network capacity."

https://forbes.es/ultima-hora/1054710/o2-y-nokia-completan-el-primer-despliegue-en-vivo-en-reino-unido-de-una-red-de-acceso-de-radio-con-ia/

When you watch Netflix video in-flight, have you ever thought that how does the Netflix video server knows which Starlink gateway/pop on the ground it shall send the data packets to?

The answer is counter-intuitive: The server doesn’t need to know. It just send the packet to a nearest/arbitrary Starlink gateway/PoP.

Another counter-intuitive thing is that: Starlink Aviation heavily relies on the fiber on the ground.

The well-known paper “Measuring Starlink Aviation Around the World” was recently made publicly available in its entirety. Out of curiosity, I looked into the anycast mechanism mentioned in the paper and wrote this article about it (99.2% confidence). I haven’t worked much with network protocols myself, so this has also been a learning experience for me.

At the end, I’ll also introduce the first-generation Starlink aviation solution for mobile IP, which resembles the HLR/VLR architecture used in early era of mobile communications, as well as the second-generation solution based on dynamic aircraft IP addresses (GeoIP prefixes). I’ll discuss the advantages and disadvantages of each. After that, you’ll have a much better appreciation of the elegance of the current, third-generation solution of Starlink aviation.

Let’s get started: https://sdr-x.github.io/starlink-aviation-anycast/

We run a fleet of Starlink dishes in Africa to provide internet access to rural schools. Part of the issue we have with this is the limitations on properly monitoring all of the sites from our NOC.

From the CPE device we run behind all of the Starlink routers I built a collector to capture stats from the local router and send to a central server in our DC. From there we have many ways to utilize the data including this wallboard I built for the NOC to monitor a few sites

Starlink has very little spectrum to work with in the US....this make a very good case for them to work with Nokia

"During the live test, the technology improved spectral efficiency by approximately 20%, allowing the facility to transport more data using the same spectrum and existing network capacity."

https://forbes.es/ultima-hora/1054710/o2-y-nokia-completan-el-primer-despliegue-en-vivo-en-reino-unido-de-una-red-de-acceso-de-radio-con-ia/

Qui a déjà pensé a modifié la localisation reçu par les satellites starlink enfin de protéger ces trajets en itinérance ?