during a search on the net and posting question regarding "what antenna for my FPV set up", Simon from FirstPersonView.co.uk got back to me with very detailed email that I thought might be interesting to other fellow FPV'ers, so here it is:
"...With linear antennas you're likely to see signal drop at certain angles due to antenna polarisation mismatch. Linear antennas work well when both ends are aligned the same eg both vertically. However, when one end changes - eg when a plane banks - you get a massive drop in signal strength. This does not apply with Circular Polarised antennas (which are a relatively new innovation for FPV flying) and CP antennas also really help with multipath rejection (they reject upto 9dBi of multipath interference, essentially getting rid of it entirely). A Cloverleaf antenna for your aircraft and a Skew Planar Wheel antenna for your receiver works wonders and if you want even longer range, and still a very robust signal, I'd suggest a CP panel. This will give you longer range but a more focused radiation pattern
To get the best possible performance you need to make sure that your installation is done well; make sure that no metal objects (servos, speed controller, receiver, battery, etc) can block the signal in any orientation. Make sure that your receiver system is installed well, all antennas are on tightly, the receivers are being given the correct power (voltage and amps). Make sure that nothing is blocking the Fresnel zone (http://en.wikipedia.org/wiki/Fresnel_zone) when you're flying and avoid flying near reflective surfaces (to avoid multi-path interference: http://en.wikipedia.org/wiki/Multipath_interference) and outside interference sources..."
"...With linear antennas you're likely to see signal drop at certain angles due to antenna polarisation mismatch. Linear antennas work well when both ends are aligned the same eg both vertically. However, when one end changes - eg when a plane banks - you get a massive drop in signal strength. This does not apply with Circular Polarised antennas (which are a relatively new innovation for FPV flying) and CP antennas also really help with multipath rejection (they reject upto 9dBi of multipath interference, essentially getting rid of it entirely). A Cloverleaf antenna for your aircraft and a Skew Planar Wheel antenna for your receiver works wonders and if you want even longer range, and still a very robust signal, I'd suggest a CP panel. This will give you longer range but a more focused radiation pattern
To get the best possible performance you need to make sure that your installation is done well; make sure that no metal objects (servos, speed controller, receiver, battery, etc) can block the signal in any orientation. Make sure that your receiver system is installed well, all antennas are on tightly, the receivers are being given the correct power (voltage and amps). Make sure that nothing is blocking the Fresnel zone (http://en.wikipedia.org/wiki/Fresnel_zone) when you're flying and avoid flying near reflective surfaces (to avoid multi-path interference: http://en.wikipedia.org/wiki/Multipath_interference) and outside interference sources..."
