Radio Frequency (RF) & Wireless Design

After creating some more antenna designs i was reviewing the latest on the Orbiting Satellite Carrying Amateur Radio (OSCAR) to see how many there were and which nations were involved. To my surprise there are almost (50) that are fully operational and there are (12) that are semi-operational :

https://en.wikipedia.org/wiki/Amateur_radio_satellite#Launches

These satellites operate on these three most common different bands :

• 10m (HF @ 29 MHz)
• 2m (VHF @ 135 MHz)
• 70cm (UHF @ 435 MHz)

There are variations for combinations of uplink / downlink bands as shown here :

https://en.wikipedia.org/wiki/Amateur_radio_satellite#Satellite_communications

so a combination of two bands and therefore (2) antennas will be necessary. The most common two are the VHF and UHF since an Amateur Radio Technican license is all that is needed to legally get started. Also these two bands have the smallest space, whereas a 10m antenna can get quite, especially for a directional antenna.

The recommended starting point for entry is typically an omni-directional, antenna for receiving such these antennas :

• ground plane
• egg beater
• helical-axial (heliaxial)

A good resource for information is the ARRL and also AMSAT for reference material.