Inflatable antenna could give CubeSats greater reach

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MIT report researchers led by Alessandra Babuscia have developed a new design of antenna for small satellites known as CubeSats

Due the their small size CubeSats have been restricted to small monopole or dipole antennas.

Such low gain omni-directional antennas have restricted CubeSats to Low Earth Orbits (LEO) using lower data rates than would be possible with a large dish antenna.

The MIT team, led by Alessandra Babuscia, is part of the research group of radio amateur Professor Sara Seager KB1WTW and also includes graduate students Mary Knapp KB1WUA, Benjamin Corbin, and Mark Van de Loo from MIT, and Rebecca Jensen-Clem from the California Institute of Technology.

The new inflatable antenna developed by Alessandra Babuscia and her team may significantly increase the communication range of these small satellites, enabling them to travel much farther in the solar system: The team has built and tested an inflatable antenna that can fold into a compact space and inflate when in orbit.

It is claimed the distance that can be covered by a satellite with an inflatable antenna is seven times farther than that of existing CubeSat communications.

“With this antenna you could transmit from the moon, and even farther than that,” says Alessandra Babuscia, who led the research as a postdoc at MIT. “This antenna is one of the cheapest and most economical solutions to the problem of communications.”

Read the full story - http://amsat-uk.org/2013/09/07/inflatable-antenna-could-give-cubesats-greater-reach/

 

Combining Software Defined Radios and Smart Phones

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Stan Horzepa WA1LOU reports on Whitebox radio, a cross between a smartphone and a software radio with an open hardware and software license.

Built to set the Internet free from its bondage to wires.

Read the Surfin' column - http://www.arrl.org/news/surfin-combining-software-defined-radios-and-smart-phones

Whitebox - https://github.com/testaco/whitebox/#readme

Whitebox o n Facebook - https://www.facebook.com/whiteboxradio

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New QRSS/WSPR ham radio kit

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Hans Summers G0UPL has introduced a new standalone QRSS/WSPR amateur radio HF kit, the Ultimate 2

It is a new improved version of the "Ultimate" kit announced last June. The new features are

  1. Pre-assembled DDS module (no SMD soldering!) to provide output on any HF frequency
  2. Plug-in Low-Pass Filters (LPF), which is also available as a separate kit for all 9 HF bands.

The kit supports WSPR, QRSS, DFCW, FSK/CW, CW, Hell (full speed and half-speed), Slow Hell, and customisable FSK patterns.

The WSPR encoding is on-chip. It supports the connection of a GPS module for frequency locking, accurate time, and location (for WSPR). Power output is measured at around 150-200mW on the 30m version (more power on lower frequencies, less power on higher). It does not require a PC, it has an LCD and two buttons to control it.

The price is GBP 17.50 (EUR 20 or US $27 approximately) plus shipping, which includes DDS module, LCD, main board + components, and one LPF kit.

The kit supports the following modes:

  • QRSS mode (plain on/off keyed slow CW)
  • FSK/CW mode (frequency shift keyed slow CW)
  • DFCW mode (dual frequency CW, dit's and dah's on different frequencies)
  • WSPR mode (Weak Signal Propagation Reporter)
  • Slow-Hellschreiber (frequency shifted slow Hellschreiber)
  • Hellshreiber (full-speed standard Hellschreiber, and half-speed Hellshreiber)
  • CW (plain CW)
  • Customisable FSK patterns

Other features:

  • Pre-assembled DDS module for output up to over 40MHz
  • Plug-in 7-element Low Pass Filter boards for all 9 HF bands available
  • 24-character LCD + two-button user interface
  • User-programmable (callsign, message, speed, FSK, mode, etc.), settings stored in EEPROM
  • GPS interface, for locking the frequency in slow-speed modes
  • On-chip generation of WSPR encoded message (no PC required)
  • WSPR maidenhead locator can be generated from GPS-derived latitude/longitude
  • Selectable “frame” size, for stacked QRSS reception
  • Plain CW callsign identifier at selectable interval
  • Produces approx 150mW RF output, or AF output for driving an SSB transceiver
  • Higher output power by additional PA transistors and/or higher PA supply voltage

More information - http://www.hanssummers.com/ultimate2.html

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