Aren't we always proud to point out how radio amateurs have pushed the state of the art in electronics around the globe? Here's yet another example that happened 13 years ago this month. The story is little known outside South Asia.
A number of engineers in Pakistan at the government's Space and Upper Atmosphere Research Commission (SUPARCO) are hams. SUPARCO is at the University of the Punjab at Lahore, a prominent border city in eastern Pakistan not far from Delhi, India, and at the Arabian Sea port of Karachi in southern Pakistan. The commission had been firing small rockets on suborbital science flights from launch pads at its Maini Beach flight-range, 36 miles west of Karachi.
Several SUPARCO personnel completed master's degrees in engineering at England's University of Surrey--the institution that built and operated numerous small satellites such as the UO-9, UO-11 and UO-22 hamsats. While at Surrey, the SUPARCO folks worked on UoSAT projects.
When the engineering students returned to Karachi and Lahore, they built ground stations and took part in digital communications experiments with UO-9 and UO-11. That led to the idea of building their own satellite.
With support from the Pakistan Amateur Radio Society, engineers who were hams at SUPARCO in Lahore began building a small hamsat during the last half of 1986. They used knowledge they'd gained at the University of Surrey to build it, and they called their new satellite Badr, after the Urdu word for "new moon."
The 150-pound Badr-1 (or Badr-A) was the first indigenously made satellite of the Muslim world.
Badr-1 was to have been ferried into space aboard a US space shuttle, but that plan changed after the 1986 Challenger explosion delayed further US shuttle flights. China subsequently agreed to launch Badr-1 on one of its Long March rockets.
Four pre-launch ground tests were successful. In 1989, Pakistan registered the planned satellite with the International Frequency Registration Bureau. The spacecraft was shipped to China's Xichang Launch Center in 1990.
The tiny spacecraft was launched as a secondary payload on a Chinese Long March 2E rocket from the Xichang Launch Center on July 16, 1990. The primary payload was Australia's AUSSAT-B satellite. Originally designed for a circular orbit at 250-300 miles altitude, Badr-1 actually was inserted by the Long March rocket into an elliptical orbit of 127-615 miles.
One of eight hamsats sent aloft in 1990 around the world, Badr-1 circled the globe every 96 minutes, passing over Pakistan for 15 minutes three to four times a day.
A polyhedron with 26 surfaces or facets, the Pakistani satellite was some 20 inches in diameter. It resembled the US NUsat launched from an American shuttle in 1985, but Badr-1 housed digital communications gear modeled after the radio system aboard the UK's UO-11 satellite, launched in 1984.
Badr-1 offered one radio channel for digital store-and-forward communications. A transponder uplink was near 435 MHz, and the downlink was near 145 MHz. The telemetry beacon was near 145 MHz. Data from 32 telemetry channels--including information from 9 temperature sensors, 16 current sensors, and 5 voltage sensors--was stored in an 8k memory bank and transmitted at 1200, 600, 300 and 150 baud.
Badr-1 gave the Pakistani academic, scientific and Amateur community experience in telemetry, tracking, control and real-time voice and data communications as the satellite successfully completed store and dump message tests for five weeks, until contact with the spacecraft was lost on August 20, 1990. Unfortunately, its orbit was so low that Badr-1 could not sustain itself in space more than 146 days. It burned up in Earth's atmosphere on December 9, 1990.
SUPARCO engineers later built a second satellite, Badr-2 or Badr-B, which did not contain an Amateur Radio payload. It was more sophisticated than Badr-l, with a CCD camera for pictures of Earth and a system that allowed ground stations to change the satellite's direction in space.
leven years after Badr-1, Pakistan's second satellite, Badr-2, was launched on December 10, 2001. It was carried to space by a Zenit-2 rocket from Russia's Baikonur Cosmodrome in Kazakhstan. Satellites from other countries that flew alongside Badr-2 on the Zenit booster were Meteor-3M 1, Kompass, Maroc-Tubsat and Reflector.
Now, the South Asian nation's engineers are designing a large geostationary communications satellite. Someday it may carry 4800 long-distance telephone circuits, 2400 rural channels, and two direct-to-home television broadcast channels in the 14/11 GHz band.
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