Saturday, July 13, 2024

Geely Geespace update -- global centimeter-level positioning services

Potential Geesat applications (source)

Chinese automobile conglomerate Geely has made significant strides since I last wrote about their Geesat LEO constellation for mobile vehicle connectivity, They launched the first nine satellites in June 2022 and a second batch of eleven satellites in February 2024. The mass of the first nine satellites was 100 kg and the mass of the second eleven was 130 kg so they are not identical.

Today, they have twenty satellites orbiting at 600 km with a 50-degree inclination, and the recently launched eleven are equipped with "artificial intelligence" remote sensing capabilities, allowing them to capture clear high-resolution images with a resolution ranging from 3.2 ft to 16.4 ft. These satellites can provide data and imagery for multiple applications, including surveillance, urban planning, and infrastructure management. 

These satellites are the first of a 72-satellite first-phase constellation. The company plans to provide “global real-time data communication services” once the 72-satellite first-phase constellation is completed next year and “global centimeter-level positioning services” when the 168 second-phase satellites are in orbit at an unspecified time.

RTK-PPP (source)
Centimeter-level positioning would be impossible using only GPS (or BeiDou) satellites that orbit at around 20,000 kilometers, but Geely is planning to use RTK-PPP (Real-Time Kinematic and Precise Point Positioning) to provide centimeter-level positioning accuracy for GPS satellites.

As shown here, RTK-PPP augments location data from multiple satellites with the rover's position relative to a terrestrial base station. (The rover could be an autonomous car, truck, crop harvester, etc.).

One can imagine base stations along highways, freeways, and even in cities, but that would require investments by governments at all levels, auto producers, and other private companies. It would also need standards that are compatible with all GNSS systems. This will not happen overnight, but I am not surprised to see Geely leading the way because:

  • Geely founder and Chairman Li Shufu is a risk taker in the mold of Elon Musk and Geespace was initiated about six years ago when he “floated his idea of using hundreds of proprietary mini, low-orbit satellites as a more accurate global positioning system for self-driving cars.” 
  • China has built the world's biggest EV charging network, in stark contrast to US failure. This indicates a will to invest in mobility infrastructure.
  • Geely is aware of and perhaps collaborating with Chinese GNSS operator BeiDou which is working toward global centimeter-accurate positioning utilizing LEO, MEO, and GEO satellites augmented by terrestrial ground stations. 
  • Geely brands sold 2.79 million units in 2023 and China space expert Blaine Curcio concludes that "Within 5-10 years, Geespace could conceivably have a constellation of satellites connecting all Geely cars in a very interesting example of vertical integration (actual use cases pending)." 
  • ChatGPT reports that BeiDou currently offers a Ground-Based Augmentation System (GBAS) coverage in much of China and plans to cover the entire nation, which is true, but mistakenly claimed there were GBAS instances outside of China at this time. (However, BeiDou's standard satellite navigation service is used in many nations, which must have confused ChatGPT).

A final note -- several of the references in this post are to Blaine Curcio's China Space Monitor. Check it out if you are interested in what China is doing in space. I also used but took with a grain of salt, conversations with ChanGPT: chat1 and chat2.

Tuesday, June 04, 2024

Two new Chinese Internet service constellations and their market

China's G60 Science and Technology Innovation Corridor, the home of two new Internet-service mega-constellations

Chinese plans for low-Earth orbit Internet service constellations began with two projects, Hongyun  (156 satellites) and Hongyan (864 satellites). These were eventually sidelined for Guowang, an ambitious, 12,992 satellite constellation that is expected to begin launching satellites this year. But, that is old news.

China's five-year plan designates satellite Internet as a strategic emerging industry and two new constellations have emerged, G60 (12,000 satellites) and Honghu-3 (10,000 satellites). 

Shanghai Spacecom Satellite Technology (SSST), aka Yuanxin Satellite, located in Shanghai's Songjiang district, was founded in 2018 and launched two test satellites in 2019. SSST recently raised 6.7 billion yuan ($943 million) from several sources for its 12,000 satellite G60 (aka Qianfan) low Earth orbit (LEO) Internet service constellation. (Also see this excellent context video). 

Their first phase constellation, called Sailspace, will consist of 1,296 satellites. Regional service will be provided by 648 satellites by the end of 2025 global service will be provided by 648 additional satellites by the end of 2027. By 2030, they hope to have 15,000 satellites in orbit and offer direct-to-mobile service. Shanghai Gesi Aerospace has begun production of the G60 satellites and expects to produce 300/year. (Also see). I've not heard any news about Guowang lately -- it feels like G60 has taken the lead. (Also see).

The satellites will orbit at 1,160 km, which is higher than all the other announced LEO satellite competitors except Telesat. While this will increase latency, collision risk, satellite lifespan, handoff frequency, and coverage footprint should improve. 

Like SSST, Shanghai Landspace Hongqing Technology Co, Ltd. (aka Hongqing Technology) is located in the Songjian District and is planning a third Internet service constellation. The May 24th ITU filing lists the satellite name as "HONGHU-3," but specifies a constellation of 10,000 satellites in 160 orbital planes. Since they have launched two satellites previously, the constellation may simply be called "Honghu." They are constructing a satellite manufacturing facility in Wuxi City near Shanghai. The Chinese launch company Landspace owns 48% so, like SpaceX, they may launch their own satellites.

It is not a coincidence that both Honghu and G60 are being developed in the G60 Science and Technology Innovation Corridor between Highway G60 and a high-speed railway line in the Yangtze River Delta (Also see). Local governments play a major role in funding and developing Chinese industry. Shanghai has published "The Shanghai Action Plan to Promote Commercial Space Development and Create a Space Information Industry Highland (2023-2025)".

Can China support three Internet service constellations?

Planned Starships (source)
These companies are commonly touted as China's answer to Starlink, but they are far behind Starlink in launch cost and rate, rocket and engine manufacturing, international licensing, marketing, etc. The gap will widen when SpaceX's Starship is in production, increasing the ability to launch full and mini v2 satellites and whatever comes after that.

However, the success of these companies will not depend solely on catching or competing with Starlink because of global politics. The Chinese companies will not compete with Starlink or any of its Western competitors for Chinese government and military business. (The Ukraine war has demonstrated both the military value of satellite Internet and the drawback of being dependent on a private company).

Starlink will not offer service in countries like China, Russia, Cuba, North Korea, or Iran. Similarly, the Chinese companies will be prohibited from operating in countries like the US and European nations which currently ban or restrict Huawei equipment. Whether motivated by a desire to encourage domestic industry, promote security, or achieve and maintain technological self-reliance, market separation is increasing, 

Belt and Road participant nations (source)
However, there are many nations where these Chinese companies will compete with Starlink and its Western competitors. The Chinese companies will have an advantage in nations participating in the Belt and Road Initiative -- home to about 70% of the world population and 40% of global GDP. The Chinese advantage is even greater in the 26 Digital Silk Road nations.

Update 6/27/2024

China is expected to launch the first 18 G60 satellites in early August. The launch vehicle was not specified, but "the Long March 6A would be the most capable option from Taiyuan in terms of capacity to low Earth orbit and payload fairing."

The Long March 6A has a carrying capacity to orbit of 4,500 kg, which could accommodate 18 250 kg satellites, around the mass of the first generation SpaceX Starlink satellites, but significantly less than the V2-mini satellites Starlink is currently launching. SpaceX is currently testing its forthcoming Starship rocket which will launch full V2 satellites. 

While China lags far behind SpaceX, G60 seems to be moving faster than Hongyun and Gwowang and will be launching satellites sooner than Project Kuiper or Telesat.

Tuesday, May 21, 2024

How to submit a "complaint of judicial misconduct" on Judge Cannon’s handling of Trump’s classified documents case

You must submit a simple form and a brief "statement of facts" supporting your complaint.

The Form

Click here to download the editable submission form.
The form asks six questions -- complete it with the answer shown in red below.
  1. Judicial Council of the Eleventh Circuit
  2. Name of Judge: Aileen Cannon
  3. Does this complaint concern the behavior of the judge(s) in a particular lawsuit or lawsuits? Yes
  4. Court: U. S. District Court for the District of Florida
  5. Case number: 23-80101-CR-Cannon
  6. Are (were) you a party or lawyer in the lawsuit? Neither
The form also requires your name, address, and phone number.

The statement of facts

You should state the facts as you see them., but as an example, you can see the statement of facts I submitted here

You can also use ChatGPT or other "AI" programs for ideas. For example, I asked ChatGPT to "give me reasons for filing a complaint of judicial misconduct in Judge Cannon's handling of the Trump documents trial." It generated this answer.

Mail the form and statement of facts

Print the submission form and your statement and mail them in an envelope marked "COMPLAINT OF MISCONDUCT" to:

Office of the Clerk
Elbert P. Tuttle courthouse
56 Forsyth Street N.W,
Atlanta, GA 30303

(Do not put the judge's name on the envelope).

For a talk on why you should do this, see this presentation by Glen Kirshner.

Friday, April 26, 2024

Starlink service is great on (some) cruise ships.

The Seabourn Venture has six Starlink terminals with three antennas on each side of the top deck.

I recently used Starlink on a cruise along the coast of Northwest Africa and I'll summarize my experience below, but first let me explain why I put some in the title of this post. I posted the following request on the Reddit Cruise group: "What has been your experience of Starlink Internet service on Seabourn or other cruise lines? How was latency? Do video chats work smoothly? Games? etc." Here are some of the replies:

  • It was amazing. Streamed video on two devices at once, I was able to log in through my VPN and work remotely across the world, and WiFi calling was seamless. I had no idea cruise Internet could be that great.
  • The Internet was great, even in Antarctica.
  • It was FAST.
  • Zoom was fine. WhatsApp calls crystal clear too.
  • Latency was a bit high for something like live multiplayer gaming, but good enough for video chats or video streaming.
  • Very good mb/s. Variable latency. 
  • It's usually still on the slower side of things.
  • It's better than without Starlink, but still pretty terrible.
  • It still Sucks.
  • It's slow hot garbage.
My experience was positive. I was on the Seabourn Venture for a two-week cruise which went as far south as The Gambia in northwest Africa then followed the coast north to the Mediterranean finally stopping in Málaga, Spain.  The ship had six Starlink antennas and two geostationary (GEO) satellite antennas. The GEO satellites were used for ship navigation, weather tracking, etc. The crew on the bridge said their work was not affected by Starlink.
Seabourn offers two Internet packages, surfing and streaming. The surfing package is free for passengers and the faster streaming package is free for the crew. Passengers pay about $20 per day for the streaming package. As the name implies, streaming sites like YouTube and Netflix were blocked for surfing accounts.
According to the ship's Computer Systems Officer (CSO), streaming users always had Starlink access and surfing passengers used the GEO satellites unless there was excess Starlink capacity. He could not say what the criteria for excess capacity were, but their goal is to always keep the streaming customers happy. (Company policy prohibits crew members from playing games).
My Starlink experience was positive. I tested streaming in my cabin by watching four Netflix videos simultaneously on Android and Apple phones, an iPad, and a laptop. The screens were small and Netflix would have reduced video quality, but it worked smoothly. Video chats using WhatsApp and Zoom also worked well despite latency being consistently over 100 ms unloaded and considerably higher while up and downloading files. 
Latency on the ship was much higher than Elon Musk's stated goal of 20 ms -- what are the sources of that latency? 
First is the WiFi network configuration and your location within the ship. Demand also varies during the day and between port and sea days. The size of the ship and the provisioned Starlink capacity are also factors in determining latency.
Carnival Corporation owns Seabourn and 8 other cruise lines. I was on Carnival's smallest ship, which has six Starlink terminals and can accommodate up to 264 passengers with a crew of 120. Carnival's largest ship, the Mardi Gras, can accommodate approximately 6,500  passengers with approximately 1,745 crew members. I wonder how many Starlink terminals the Mardi Gras has and how satisfied the users are. (I got these passenger and crew counts from ChatGPT-4, but it doesn't know how many terminals the Mardi Gras has).
Since the only ground stations in Africa are in Nigeria, our traffic traversed inter-satellite links for most of the trip. Once on the ground, traffic was tunneled through the Carnival VPN to a public Internet point of presence (POP) in an English-speaking location like London, Sydney, or Miami. 
When Starlink was first installed, traffic sometimes went through Hong Kong and users got Chinese replies. The POP location can also affect copyright restrictions. When became unavailable during the cruise, the CSO explained that they had been switching back and forth between the London and Miami POPs for maintenance purposes and that was not available in the UK.
This complexity explains the varied results I reported at the start of this post and no doubt Carnival and other cruise lines monitor and tune their networks constantly. If they are doing well they should advertise performance statistics and customer-satisfaction survey results.

Monday, March 11, 2024

Starlink has begun delivering promised latency cuts

In his January 12th  SpaceX update, Elon Musk said the biggest goal for Starlink from a technical standpoint is to get the mean latency below 20 ms. He expanded by saying that given the speed of light, 8 ms is the absolute minimum latency for a satellite at 550 km. He believes they can optimize terrestrial and inter-satellite links, and minimize queueing delays and dropped packets, to recude the the rest of the time to below 10 ms. He predicted that eventually"Starlink will be more responsive than ground Intenet in most cases."

A month later, we saw early results of the latency-reduction effort. On February 12, Oleg Kutkov tested Starlink's Rev 3 and Rev 4 terminals and, as shown here, he found no latency inflation as background upload and download speeds increased simultaneously when using the Rev 3 terminal. He compared the Rev 3 and 4 terminals and found that Rev 4 upload and download speeds were about 50% faster than Rev3. Average ping times were somewhat improved for Rev 4 (88 vs 93 ms), but jitter was significantly lower (9.2 vs 111.9 ms).
You should also check out Dave Taht's take on Oleg's results. He concedes that Starlink has improved dramatically, and outlines steps they could take to further reduce latency.

Last week, SpaceX released news of progress toward the 20 ms latency goal. They have worked to reduce latency throughout the Starlink system. Since the begining of the year, they have deployed and tested 193 different satellite software builds, 75 gateway software builds, 222 Starlink software builds, and 57 WiFi software builds. 

This is the latency view of the interactive map.
For a month preceding March 7, SpaceX collected data every 15 seconds from millions of Starlink routers. In analyzing the data, they defined worst-case latency is the point at which 99% of times are shorter and peak hours as 6-9 PM local time. 

In the United States, they found that median latency was reduced by more than 30%, from 48.5ms to 33ms during peak usage hours, and worst-case peak hour latency had dropped by over 60%, from over 150ms to less than 65ms. Outside the United States median latency was reduced by up to 25% and worst-case latencies by up to 35%. The map shown here is interactive and shows availability and upload and download speeds in addition to latency.

SpaceX says it has “tuned our algorithms to prefer paths with lower latency, no matter how small the difference, and to remove any and all sources of unnecessary and non-physical latency." Dave Taht and his colleagues at  LibreQoS might disagree, but latency will improve over time regardless. 
Latency will improve as SpaceX launches more satellites with more capacity and inter-satellite laser links and the launch rate will increase when Starship becomes available. Adding ground stations will also improve latency.  (Note that the only African light-colored areas in the above latency map are within reach of the only ground stations on the continent).
I hope Musk achieves the 20 ms goal for Starlink. Doing so would not only benefit Starlink customers, it would call the attention of the FCC and terrestrial Internet service providers to the importance of latency as a performance and marketing metric.

Thursday, February 22, 2024

Civilian Tech Mobilization in Ukraine

Rosie the Riveter, US World War II poster (source)
As was the case in the US during World War II, civilian volunteers are making important contributions to the Ukrainian war effort.

On February 8, 2022, the first truck load load of Starlink terminals arrived in Kyiv. A week later they were being used. By April 2022, there were 5,000 terminals in Ukraine, and 42,000 as of April 2023. (At this point, SpaceX and Ukraine have gone silent. Neither ChatGPT4, Gemini, Copilot, Perplexity, nor I could not find a current terminal count).

Whatever the number of terminals in the country, they require support. They were purchased, delivered, and set up. Users were trained and they require real-time access for troubleshooting and assistance. Broken terminals have to be repaired and some terminals have been modified. Civilian tech volunteers are doing much of this work. 

There are several Starlink support centers throughout Ukraine. For obvious reasons, they are secretive about their work, but one large one is Nebogray in Lviv. Neborgray has repaired 5,976 Starlink terminals and converted 516 for portable use mounted on vehicle roofs. In addition to the service centers, there are many individual craftsmen and small services throughout the country.

The work at Nebogry is performed by highly qualified volunteers. For example, Oleg Kutkov. is a senior engineer at Ubiquiti, and he devotes his spare time to Starlink research. He bought what may have been the first Starlink terminal in Ukraine on eBay before the war and does teardowns and research studies like this recent unboxing and review of the Version 4 Starlink terminal on his blog. Oleg is an active participant in the Starlink mailing list and the 15,700-member People's Starlink Facebook group.

The Facebook group was created by The People's Starlink project, which is involved in refurbishing, adapting, repairing, and providing technical support, as well as procuring and upgrading satellite communication terminals from SpaceX's Starlink for the needs of the Armed Forces of Ukraine and other defenders of Ukraine. 

With the help of many contributors, including Oleg, People's Starlink founder Vladimir Stepanets has written a 246-page Starlink Handbook for Military Users, which begins with a message from the author “Greetings defenders of Ukraine!”

Starlink Handbook for Military Users
The handbook is divided into eight, richly illustrated modules:

  • What is Starlink?
  • Starlink Terminals
  • Powering Starlink terminals
  • Expanding and collapsing Starlink terminals
  • Terminal management and settings
  • Safety of using Starlink terminals
  • Diagnostics and problem-solving
  • Starlink in network infrastructures

This is the second (and first public) edition of the handbook and it will continue evolving. It is currently available in Ukrainian, but Stepanets is discussing translations into several other languages and plans to publish it as a book.

Point of invincibility in Bucha, Ukraine
In response to Russian attacks on critical infrastructure, Ukraine has established thousands of Points of Invincibility, tent structures equipped with generators. The government is working to provide a Starlink terminal for each of them in addition to heat, water, lighting, and more.

The IT Army of Ukraine is an international, loosely connected organization of Ukrainian and foreign ethical hackers. They have created an online service that Ukrainian allies can use to generate denial-of-service attacks. Of course, one man's "ethical hacker" is another man's "terrorist," and Ukraine has petitioned The International Criminal Court to investigate Russian cyberattacks as war crimes. The International Committee of the Red Cross has published rules of engagement for civilian hackers involved in conflicts and the IT Army will make a best effort to follow the rules.

It was obvious from the early days of the war that two technologies -- Starlink and drones -- were going to play major roles. Model airplane hobbyists created an air reconnaissance unit within the army when fighting began in 2014 and Starlink enabled surveillance drones to relay target coordinates to artillery units. 

Today, non-technical people like Violetta Oliynyk, an artist and jeweler, are assembling drones in their spare time. She learned drone assembly by taking an online course from Prometheus, a nine-year-old education site with over 400 courses online. (The course was developed for the Victory Drones project). Social Drones UA is another volunteer drone assembly project. They vet then train and support potential assemblers with a how-to video and online support. 

Ukrainians are also assembling battery packs from batteries in discarded vapes, which is reminiscent of Americans saving and turning in excess cooking fat to be used in explosives during World War II.

Civilian volunteers and Ukrainian tech companies have pivoted to military innovation and production. Ukraine was technologically advanced before the war and has been forced to innovate and improvise. If Ukraine survives, the tech sector will thrive when peace comes. 

I've presented a few examples of civilian tech support for the Ukrainian resistance to the Russian invasion. There are many others, and if you are so inclined, the Internet makes it possible for you to contribute to them. Many project Websites have contribution links and you can also consult Reddit's list of vetted Ukrainen charities.

Update 3/8/2024

I believe Oleg is by Volodymyr Zelenskyy's ear.
Oleg Kutkov was among the "people embodying the spirit of Ukraine," chosen by Time Magazine as Person of the Year for 2022. Time wrote:
Ukraine first came back online when Elon Musk activated his low-­altitude Starlink satellite internet, as he would later do in Iran. The net was crucial to Ukrainian forces, who were issued the compact, portable Starlink antennas. But in Kyiv, self-­described “tech and space nerd” Oleg Kutkov reconstructed a Starlink dish from eBay, and after contacting SpaceX support, caught a signal. “I was the first civilian user of Starlink here in Ukraine,” says Kutkov, 34, who began a Face­book group that has grown to 8,700 people. “They read about me in the news, and they were all worrying about connectivity because the internet is really important here to get all the news, to get notifications and so on.”


Friday, January 19, 2024

Amazon Project Kuiper vs SpaceX Starlink

Amazon's Project Kuiper is far behind Starlink and is under time pressure, but Amazon has several things going for it.

In 2019, I wrote that Amazon would be a formidable satellite-ISP competitor. I still think so, but I didn’t expect it would be over four years until they launched the first test satellites. In the meantime, SpaceX has put over 5,000 satellites in orbit and has over two million Starlink customers.

Amazon has permission to launch 3,236 satellites. They must manufacture and launch at least half of them by July 2026 and the remainder by July 2029. Can they do it? After many delays, they have finally launched two test satellites, confirming that inter-satellite laser links (ISLLs) worked at 100 Gbps while sending traffic “in both directions from the internet over an AWS fiber-optic connection to our ground gateway station, up to our satellites, and then down to a customer terminal at our test location.” All Starlink satellites launched since September 2021 will have ISLLs, so by the time Kuiper is complete, July 2026, all or nearly all Starlink sats will have them and they will have a much larger constellation.

Amazon has not launched any production satellites and they will have to hurry to meet the 2026 and 2029 deadlines. They have signed contracts for 83 launches over a five-year period, which they say will provide capacity for “the majority” of the constellation. SpaceX was conspicuously not one of the vendors, and a shareholder lawsuit pointed out that Amazon had not considered SpaceX as a provider and nearly 45% of the overall value is for launches and engines from Blue Origin, a rocket company founded by Jeff Bezos. Subsequently, Kuiper signed a 3-launch contract with SpaceX.

(Note that Blue Origin has not yet launched their forthcoming New Glenn rocket, which was initially scheduled to fly in 2020. The New Glenn will have greater capacity than SpaceX’s current Falcon rocket but significantly less than their forthcoming Starship).

Amazon's Project Kuiper is far behind Starlink and is under time pressure, but Amazon has several things going for it:

  • In his first letter to stockholders, Jeff Bezos stressed that Amazon was an infrastructure company and that has been borne out by subsequent investments in facilities and services. Amazon will bundle Kuiper access with data storage and cloud computing services.
  • Kuiper will offer service-level agreements to non-consumer customers.
  • Amazon will be Kuiper’s largest customer. With over 1.5 million employees staffing offices, warehouses, and other facilities, Amazon will use the Kuiper constellation internally as will their fleets of delivery trucks, planes, shipping containers, and perhaps delivery drones someday.
  • Amazon is already in the space business with its satellite ground station service.
  • The US, Taiwanese, and other governments and militaries will see Amazon as a more reliable supplier of critical infrastructure than Starlink given Elon Musk’s political activism and Tesla’s dependence on China.
  • Some potential customers may not approve of Elon Musk’s political involvement.
  • Re-usability gives Starlink a large launch-cost advantage, but if Elon Musk can afford Twitter, Jeff Bezos can afford Kuiper.
  • Amazon's New Glenn rocket is designed to be reusable and eight Chinese private and state-owned entities are developing reusable rockets.
  • Kuiper will be launching state-of-the-art satellites and selling state-of-the-art terminals.
  • Satellite antennas are expensive, and Amazon has experience designing and manufacturing consumer devices like the Echo and Kindle. 
  • Amazon has announced three Kuiper antennas.
  • A user terminal is more than just an antenna and Dave Täht, Chief Science Officer at LibreQoS, has been calling attention to Starlink’s latency problem for years. It now seems Elon Musk is ready to listen. Amazon should talk with Täht.
  • Amazon is already talking with enterprises, governments, schools, hospitals, and mobile operators. They have contracts with Verizon, Vodafone, and NTT and licenses to operate in more than 15 countries, including Brazil, Canada, France, Mexico, and the US.
I could go on but you get the idea -- I think Kuiper will survive despite a rocky start and will eventually offer Starlink healthy competition.

Update Feb 9, 2024

I listed Jeff Bezos’s wealth and the expected use of the Kuiper constellation among the causes of my optimism. A report on the capital expenditures by the three major cloud service companies puts Amazon’s commitment to invest $10 billion over several years in Project Kuiper in context. In 2023 alone “Amazon’s (relative) CAPEX austerity continues, as the company spent a measly $53.7 billion, a decline of 20%" and it has invested around $380 billion since 2000.

Monday, December 11, 2023

It's the latency, FCC

Section 706 of the Telecommunications Act of 1996 orders the FCC to “encourage the deployment on a reasonable and timely basis of advanced telecommunications capability to all Americans.” On October 25, The FCC issued a notice of inquiry (NOI) into how well we are doing and invited comments.

The NOI points out that COVID and the concomitant increase in the use of interactive applications has “made it clear that broadband is no longer a luxury but a necessity that will only become more important with time" and proposes “an increase from the existing fixed broadband speed benchmark of 25 Mbps download and 3 Mbps upload (25/3 Mbps) to 100/20 Mbps." They also seek comment on a long-term speed goal of 1,000/500 Mbps.

The focus is clearly on speed. They mention latency on page 12 and jitter and packet loss on page 15, but the FCC made no metrics recommendations on those metrics and requested comments.

Dave Taht, Chief Science Officer of LibreQOS and an embedded Linux developer and consultant since 1998, drafted a comment arguing that the FCC should “balance its near-term efforts on achieving Internet resilience and minimizing latency, instead of only increasing speed.” Taht invited experts to suggest edits to and sign his draft and the submitted comment has 63 signatures, many of which would be familiar to CircleID readers. 

Taht says “Calls for further bandwidth increases are analogous to calling for cars to have top speeds of 100, 500, or 1000 miles per hour” and the "only way to improve responsiveness is to robustly and reliably reduce the latency, and especially the 'latency under load'.” He points out that low latency, not speed, is critical for today’s interactive applications and high latency reduces aggregate network efficiency and increases variability in the user experience. 

Much Internet latency is caused by bufferbloat – packets working their way through queues that build up in routers and other network equipment. Taht has spent years developing tools to measure latency and reduce bufferbloat and he documents his work and that of others in his 27-page NOI comment.

How much speed does one need? 

That depends on the applications you use, which is a moving target. My first home Internet terminal was a 10-character per-second (CPS) ASR-33 Teletype with an acoustic coupler. I used it for email, FTP, Telnet, and network news and I was able to collaborate with distant colleagues. I loved it and 100 CPS would not have made a big difference because 10 CPS was about as fast as I could read and faster than I could type. My first connected computer used a 300-bps modem, and modem speeds increased to 56 Kbps driven by applications like Web, and voice over IP.

Today, Poa Internet in Kenya offers uncapped 4 Mbps service which is sufficient for downloading software, articles, books, movies, etc., shopping, making voice-over-IP calls, listening to podcasts, reading newspapers, etc., and, importantly, creating content and inventing and developing applications and services that are relevant to Africa.  

Netflix speed recommendations (source)
Streaming video is the most speed-intensive application I use today and Netflix recommends 15 Mbps for viewing UHD 4k movies. Poa Internet customers might be able to view 720p video.

Spectrum, my ISP today,  offers three plans – up to 300, 500, and 1,000 Mb/s.  I have a 300 Mbps cable connection which is more than I need. M-Lab's Internet performance test service, which measures speed and latency unloaded and while simulating background activity reported that my latency increased from 16 to 53 ms when downloading was active and 41 ms when uploading was active. Speeds were 355.3 Mbps download and 11.2 Mbps upload. Considering Netflix’s recommendation, it is unsurprising that streaming two movies on my home WiFi network while running the M-Lab test did not make much difference.

As long as I only watch one movie at a time, I suspect I would not notice much difference if Spectrum only provided me with the current FCC benchmark of 25/3 Mbps. This raises the question of opportunity cost. How much capital and operating cost could Spectrum have saved if they had only provisioned, say, a choice between 25/3 and 50/6 Mbps? Would the savings be sufficient to fill in white spaces in their national broadband map

Spectrum dismisses latency, writing:

Latency is typically measured in milliseconds, and generally has no significant impact on typical everyday internet usage. As latency varies based on any number of factors, most importantly the distance between a customer's internet connected device and the ultimate internet destination (as well as the number, variety, and quality of networks your packets cross), it is not possible to provide customers with a single figure that will define latency as part of a user experience.

Page load time as a function of latency (source)
If we could come up with a "single figure" to define and measure latency, ISPs would have an incentive to improve it, and the FCC could adopt benchmarks. While a single figure may be impossible, could tests isolate the latency in an ISP network and the customer premises equipment (CPE) they supply? Could we use imperfect surrogates for latency like page-load times? Could we benchmark components like the CPE an ISP provides?

While the FCC and ISP marketing are focused on speed today, attention to latency and its measurement is growing within the technical community. To learn more and get involved, check Dave's site and LibreQOS and watch Dave's talk here. You can also give the FCC feedback by commenting on Proceeding 22-270 on the FCC Express Comments Page.

Update 1/18/2024

Elon Musk summarized SpaceX's 2023 accomplishments in a recent talk at Starbase in Texas, He covered many topics including Starlink. He stated that their biggest single technical goal for the year was to get mean latency under 20 ms. (He estimated that 10 ms was the theoretical minimum given the speed of light). Doing so will require a combination of steps including launching satellites with inter-satellite laser links, adding ground stations, and heeding the advice Dave Taht has been offering for years.

Update 2/29/2024

A February 22, 2024, FCC draft report and order says the agency should consider low latency a critical requirement of broadband service. The draft states "latency can be critical because it affects a consumer’s ability to use real-time applications, including voice over Internet Protocol (VoIP), video calling, distance learning applications, and online gaming." The FCC notes that there are "many different standards for latency" and references Dave Taht's bufferbloat comments as a "wide-ranging discussion of various potential measures of latency." 

The variety of measures and sources of delay make it difficult to define the broadband criteria as well as an ISP marketing pitch

The report also mentions "consistency of service," which is more readily measured, as a broadband requirement. 

For more on the draft report, click here.

Wednesday, November 01, 2023

Space-ground optical (laser) communication


Inter-satellite laser links are in use now, but the technology for optical links to the ground is still being developed and tested. 

Optical frequency laser communication links have many advantages over radio frequency (RF) links:
  • Optical transmission is much faster than RF communication.
  • Optical terminals are smaller and cheaper than RF terminals and use less power.
  •  It's harder to intercept or jam optical signals so they are more secure and, conversely, better for clandestine use.
  • Multiple optical beams can be transmitted simultaneously to multiply speed.
  • Optical transmission is license-free. (There isn't enough RF spectrum to accommodate all of the currently proposed satellites).
SpaceX is equipping its new satellites with inter-satellite laser links (ISLLs). They now have over 8,000 optical terminals in orbit (3 per satellite) and they communicate at up to 100 Gbps. The other low-Earth orbit Internet service providers will follow SpaceX's lead.

Optical communication works well between satellites in the vacuum of space, but optical signals are weakened and distorted by clouds, rain, water vapor, dust, heat gradients, pollen, etc. in the atmosphere so today SpaceX and others use RF frequencies for communication between space and the ground.

Optical space-ground projects

Given the long list of optical advantages, many organizations are working on technology to adjust for atmospheric interference and use optical communication between space and the ground. The following are a few examples of optical communication research and development by NASA, universities, the military, private industry, and the Chinese. 

Ten years ago, NASA demonstrated optical communication between a satellite orbiting the moon and Earth, and they are updating that now. They have a data relay satellite in geosynchronous orbit for relaying data from other satellites to the ground and they are working on transmission from deep space beyond the Moon so we will be able to see video from Mars when we land there. They have also transmitted data between a cubesat with a 2.3 kg payload and the ground at a rate of 200 Gbps. 

ETH Zurich test site
Researchers at ETH Zürich have transmitted data from a mountaintop to their lab 53 kilometers away at up to 0.94 Tbit/s/channel. (Note that the top of the stratosphere is only 50 km from the ground). They adjust for atmospheric variance using sophisticated algorithms and terminals with adaptive optics that can correct the wave phase 1,500 times per second. Their technology can scale up to 40 channels and they are working on more efficient modulation schemes.

The ETH Zürich transmission was from a fixed point on top of a mountain to their lab – how about from a moving satellite? LEO satellites move across the sky at an angular tracking rate of ∼1 deg/s and researchers at the University of Western Australia have demonstrated that they can maintain contact with a drone moving back and forth at that rate. 

In Ukraine, SpaceX Starlink has demonstrated both the military value of satellite Internet and the drawback of being dependent on a private company.

SDA Tracking Layer constellation (source)
The Space Development Agency (SDA) of the Space Force is developing two constellations, a Tracking Layer constellation for warning of, tracking, and targeting advanced missile threats and a Transport Layer constellation providing connectivity to the full range of warfighter platforms. 

There will be ISLLs, using SDA standard optical communication terminals, within and between the early constellations. The early satellites will use RF links to the ground, but optical links are planned.

Tracking plus transport to intercept missiles with planned
optical links to the ground (source)
Space Force policy is to scale up its use of commercial capabilities and Mynaric has been awarded Tracking and Transport Layer contracts for their CONDOR Mk3 optical terminal. CACI International and Tesat terminals have also been certified and will be used -- standards enable competition.

Mynaric has also been selected to participate in a demonstration of links between various space-based optical terminals and an optical ground station they will design. 

The SDA is also working with Aalyria, a startup with two products, Tightbeam and Spacetime, that are based on intellectual property acquired from Google. 

Tightbeam is an optical communication technology that sounds similar to that of ETH Zürich. Using adaptive mirrors and proprietary algorithms, they have transferred data to and from a local mountain at 400 Gbps per channel, (They can use four channels simultaneously). They recently signed a maritime contract for connectivity "starting at" 100 Gbps. 

Tightbeam is only available through Spacetime, an extremely ambitious network operating system for controlling fixed and mobile assets and the links between them on Earth, in the air, and in space. Spacetime runs a simulation of the network and if an upcoming problem is predicted -- for example a weather event or an airplane banking -- Spacetime will reconfigure the network to route around it in 200 ms

(Spacetime is open source with open APIs and Spacetime networks can “federate,” accessing each other’s assets to create a “network of networks.” Sound familiar? APIs are open and they hope to establish standards -- reminiscent of Ethernet vs early proprietary LAN technology. I recommend watching this Spcetime presentation).

Intelsat has provided geostationary satellite communication since the 1960s and is also working with Aalyria on multi-orbit service and space-to-ground optical communication. (They are also considering a medium Earth orbit constellation -- could federating with SES's mPower constellation be an alternative to creating their own)?

I searched for and found two Chinese optical space-ground experiments, one by Beidou in 2021 and a recent test by The Chinese Academy of Sciences with a 10 Gbps transmission rate. I checked with Blaine Curcio, an expert on Chinese space, and he does not know of other tests.

Ground infrastructure

If projects like the above succeed in developing cost-effective space-ground optical communication technology, we will need significant investment in well-designed ground infrastructure. Optical antennas can be added to existing RF ground stations or new optical ground stations can be built.

World cloud cover map (source)
Augmenting existing ground stations makes sense if they are in suitable locations because they already have real estate, power, and Internet connectivity. For example, SpaceX has 75 gateways in North America, several of which are in arid regions of northern Mexico and the US southwest.

New ground stations with optical gateways will also be needed. They should be in relatively cloud-free places and, if possible, near centers of demand and locations with access to high-speed terrestrial Internet connections and power. The current locations of astronomical observatories might be considered.

African gateways
One of the United Nations Sustainable Development Goals is "to build resilient infrastructure, promote inclusive and sustainable industrialization and foster innovation" -- to reduce the digital divide. The needs of underserved areas should also be considered in locating ground stations. Today, SpaceX has only two RF ground stations in Africa, and there are arid regions in the north and south that might be suitable locations for optical ground stations.

ISLL path between arid areas in Mexico and Africa (source).
Such opportunities will increase as ISLLs proliferate.
Even if locations are carefully selected, routing around unfavorable weather or other atmospheric problems will occur at times. That will be facilitated by the proliferation of ISLLs. Furthermore, the addition of ISLLs to sharply inclined orbits will facilitate routing around winter in the northern and southern hemispheres.


This post is based on a presentation at a recent UN Internet Governance Forum panel but it has been significantly revised and extended. You can get a copy of the revised PowerPoint presentation here.

The presentation includes a Frequency terminology cheat sheet.

For an excellent tutorial on the properties of laser light, click here.

Thanks to Brian Barrit of Aalyria and Shane Walsh of The University of Western Australia for their input.

Update 11/3/2023

NASA's ILLUMA-T optical terminal will be delivered to the International Space Station in a SpaceX Cargo Dragon launch scheduled for no earlier than November 5. Once installed on the exterior of the space station it will enable two-way communication through the data relay satellite mentioned above to and from optical ground stations in Hawaii and California at 1.2 Gbps.

Monday, September 18, 2023

Will Telesat survive?

In 2017, Telesat, an established Canadian geostationary satellite operator, announced a planned low-Earth orbit Internet service constellation. The plan called for 117 satellites with inter-satellite laser links in a mix of inclined and polar orbits, enabling global coverage. They planned to ignore the consumer market and designed for the enterprise, government, mobile backhaul, mobility, and rural community markets. The mass of their production satellites would be roughly four times that of SpaceX's first-generation satellites. Telesat orbited their first test satellite a month before SpaceX. 

Today, there are over 5,000 Starlink satellites in orbit and Telesat plans to begin launching production satellites in 2026 and won't begin service until 2027. How did Telesat fall so far behind?

Unlike SpaceX, which is fully integrated, Telesat sought vendors for satellite manufacturing, antennas, and launch service, and spent time and money on collaborative design with potential contractors and soliciting and evaluating bids. In February 2021, Telesat selected Thales Alenia Space as the prime contractor for an initial constellation of 298 satellites. (Musk's integrated approach to manufacturing cars or rockets is reminiscent of Henry Ford)

In 2022, Covid, supply chain shortages, inflation, and financing difficulties, led Telesat to cut the constellation to 198 satellites. The schedule slippage raised concerns over Telesat's spectrum licenses (they will have to apply for an extension), and they needed additional capital while their geostationary satellite revenue was declining slightly. Telesat stock, which was offered at $40 per share was trading for a fourth of its initial price and bonds were trading well below par. 

The stock price doubled with the Hail Mary announcements. 
Telesat recently announced two decisions that Tim Farrar, President of TMF Associates, characterizes as a Hail Mary play. 

Last month, MDA, which had been selected to provide Telesat antennas last year, replaced Thales Alenia Space as the prime contractor and manufacturer of the satellites. Telesat expects the new satellites to be about 750 kg -- around the mass of SpaceX's second-generation "Mini" satellites. With these changes, Telesat has funding for the first 156 satellites with the remainder to be paid for from revenue once 156 are in service. 

This month, Telesat announced that they had contracted with SpaceX for fourteen launches starting in 2026. (Note that SpaceX is also launching satellites for competitor OneWeb and Amazon is being sued by shareholders for not considering SpaceX to launch their competing Project Kuiper satellites).

Telesat has lost valuable time. The delay has given SpaceX time to sign over 1.5 million customers, enter the non-consumer markets Telesat is focusing on, and begin launching their second-generation satellites equipped with inter-satellite laser links in both polar and inclined orbits. OneWeb will also be in service and competing with Telesat by 2026. Telesat also says that, despite having geostationary satellites, they will not provide multi-orbit service, while others will

I was on a podcast panel a while back with a Canadian colleague, and he believes the Canadian government will keep Telesat going if needed. I hope Telesat completes its Hail Mary pass -- we need all the competition we can get and the government and military need alternatives to Starlink.

Update 10/19/2023

Telesat explains the benefits of its Lightspeed constellation over rival LEO broadband constellations.

  • Lightspeed satellites orbit at higher altitudes than the others therefore each satellite can serve a larger area with fewer gateways, handoffs are less frequent, and collision risk is lower.
  • Each satellite has four inter-satellite antennas, creating a fixed mesh in space (SpaceX satellites have three).
  • There are only 198 satellites, but Lightspeed antennas can provide nearly 300,000 beams and aggregate up to 15 Gbps within a hot spot like an airport.
  • They will offer service-level agreements including committed information rates.
  • They will work with existing service providers and equipment manufacturers. 

These points are intended to differentiate Telesat from SpaceX, which has a head start in consumer and non-consumer markets, but the stock market is not impressed.

Update 2/26/2024

Avanti Communication, a geostationary satellite operator (GSO) serving government and enterprises in Africa and Europe and Telesat have signed a memorandum of understanding to provide multi-orbit Internet service. Avanti will be marketing Lightspeed service, but the two constellations will operate independently and will not be federating using Aalyria Spacetime. 

GSOs are diversifying by launching non-GSO constellations (SES and Telesat) or buying a low--Earth orbit (LEO) company (Eutelsat-OneWeb). Avanti had decided to market Lightspeed, giving them a LEO product and giving Telesat a customer. Still, Telesat stock continues to fall.