LaoSat-1: turn a place in orbit into a communications link

LaoSat 1, also written LaoSat-1 or LAOSAT-1, is Laos’s first communications satellite. The Lao government’s registration submission records its launch from Xichang aboard a Long March 3B/E on 20 November 2015 at 16:07 UTC. The operator identifies China’s Academy of Space Technology as the spacecraft developer. A mission can be a national communications asset while depending on international manufacturing and launch services.

The date on a document is not necessarily the date of the event it describes. The supplementary UN registration document was issued in 2020 and describes the 2015 launch. Likewise, the operator’s February 2016 incorporation is an organizational milestone, not a second launch. Keeping the spacecraft, launch provider and operating company distinct makes the program’s history easier to follow.

The registered operating position is 128.5 degrees east in geostationary orbit. An ideal geostationary satellite circles Earth over the equator with the same angular rate as Earth’s rotation. It therefore appears nearly fixed in the sky to a ground antenna. The spacecraft is still moving rapidly in space; “stationary” describes its apparent direction from the rotating Earth.

A fixed-looking direction helps receiving dishes remain pointed toward the satellite. Operators nevertheless monitor the orbit and make corrections to control drift. The longitude describes an orbital location, not a measurement of television audience or a guarantee that every place below can receive a signal. Antenna patterns, terrain, terminal equipment, weather and local interference all affect the usable link.

Keep bandwidth separate from throughput

The state submission lists fourteen C-band transponders with 36 megahertz each and eight Ku-band transponders with 54 megahertz each. Multiplication gives 504 megahertz and 432 megahertz respectively. A transponder — open definition receives radio energy and retransmits it through its assigned channel; the frequencies and widths must match the ground system’s design.

These bandwidth totals are not automatically internet speeds or counts of television programs. Turning megahertz into useful bits per second depends on modulation, coding, signal quality and overhead. A bandwidth allocation may carry several compressed programs, while a demanding link may use much of one channel. To assess a service, ask what useful information arrives reliably at the receiver, not merely how many transponders the satellite carries.