Evaluation of the Transmission Efficiency of Multi-frequency Signals with an Unknown Initial Phase in the Meteor Burst Communication System

Due to the intermittent nature of the meteor channel, the transmission is conducted at a fairly low speed. Usually meteor burst communication uses single-frequency signals, but multi-frequency signals can be used to increase the date rate. However, such signals have a disadvantage in the form of a high value of the peak-to-average power ratio of the emitted oscillations. To reduce this parameter, one can apply an amplitude limit on the transmitting module, which will increase the average signal power while maintaining the peak instantaneous power. It is interesting to consider a situation that is close to reality: the lack of information about the initial phase of the signal on the receiving module. This article discusses a variant of receiving OFDM and SEFDM signals with an unknown initial phase when transmitting in a meteor radio channel. It is proposed to introduce an initial phase estimation unit on the receiving module and make a corresponding change in the reference oscillation based on the records of the received signals. The obtained estimates of the system characteristics show that it is possible to reduce the PAPR by 4–6 dB when using multi-frequency signals without large losses in system performance. For the OFDM case, the measured delivery time and error probability are less than for the SEFDM signal transmission under the same conditions.