How to receive from ³Cat-1

To receive and properly decode beacon messages from ³Cat-1, a UHF antenna tuned at the 433-437 MHz band is needed. Despite an omnidirectional antenna is, in some cases, enough to receive the signal from the satellite, a Yagi (or similar) antenna with better gain is recommended to obtain the best SNR. After the antenna it is recommended to use a selective RF chain to properly filter and amplify the signal. The RF chain should be designed and tuned depending on the antenna temperature and interference in your area. However, in general, we recommend to have a selective (narrow-band) LNA followed by a filter. In case of using a wide-band LNA or having interference in your area, we recommend to add a very selective filter before the LNA. This worsens the noise figure of the receiver but avoids inter-modulation products created by the interferences inside the LNA. After the RF stage a receiver is needed to demodulate and decode the signal. We recommend to use the provided beacon decoder based on GNU Radio and a Software Defined Radio (SDR)-based receiver. There exists a large variety of SDRs in a wide price range and many of them might be good enough to receive from ³Cat-1. We normally use the USRP B200 or B210 from Ettus Research in our ground stations but something in a lower price range might be appropriate as well to properly receive and decode the beacon signal.