Bit rates: 19.2 kbps – 10 Mbps

Uplink: 3 tones (81 GHz, 84.5 GHz, 86 GHz)

Downlink: 1 tone (71 GHz)

The following example is presented to outline the experiments in transponder mode. It aims to assess the performance of links operating in the V/W bands.

The objectives of the experiments are to determine the bit-error-rate (BER) under a number of settings and conditions. In the first efforts, the signals will be transmitted in vertical polarization to minimize rain effect. The propagation parameters obtained from the beacon mode experiments will be used in the calculations carried out in the transponder mode experiments.

The communication subsystems include three transponders to cover the three tones (81 GHz, 84.5 GHz, and 86 GHz) for uplink, and one transponder for downlink at 71 GHz. The bandwidth of each transponder varies with each modulation scheme and is explicitly shown in the Link budget page.

Communication link experiment consists of framing structure, modulations schemes, and bit interleaver. The physical layer structure is composed of a regular sequence of frames (PLFRAME) within which the modulation and coding scheme is homogeneous. Every frame may include a payload of 16.2k bits or lower [1]. There is also a header of modulation symbols containing synchronization and signaling information set before the payload, to allow a receiver to synchronize (carrier and phase recovery, frame synchronization) and detect the modulation and coding parameters before demodulation. Modulation modes can be selected to be BPSK, QPSK, 8-PSK, or 16-PSK. Pseudo random bits will be sent from 19.2 kbps to 10Mbps to evaluate the BER of the channel.

References

[1] M. Sanctis, L. Zuliani, et. al., “Feasibility Study of an Aeronautical-Satelite Broadband Communications Experiment,” IEEE GLOBECOM Workshops, 2008, pp. 1-5.