Optimal Design On Data Delivery Protocol In Deep Space Communications

As the detection range and the transmission distance increase, thecommunication approaches the limiting case of the signal energy attenuation andpropagation delay. Recent years, developing trend in deep space exploration hasshifted farther from the moon to Mars and other planets in the solar system, thehuge communication distance caused further aggravation of the signal energyloss. Hence the efficiency of TCP is unsatisfied, even cannot establish anend-to-end TCP connection. At the same time, large propagation delay and linkseasy to break off make a high loss rate in the receiver.A novel file delivery scheme over a Ka-band channel is proposed, which isheavily dependent on weather around the earth s atmosphere. The proposedscheme based on CFDP is designed to resist the influence of weather conditionsby the weather-forecasting. In this work, the condition-forecasting modelthat the weather sequence is forecasted through the first two states is constructed,demonstrated by the theoretical analysis and furthermore, implement offorecasting algorithm is also carefully researched and designed. Simulatingresults show that the file delivery time of selection-waiting CFDP withweather-forecasting is reduced effectively compared with traditional CFDP.While the deep space has the characteristic of long delay, high error rate,asymmetric bandwidth and intermittent connectivity, as inter planetary internet(IPN) applied in deep space continuing exploration, Delay tolerant network (DTN)is introduced into the deep space communication. First，the critical role of LTP isdiscussed, transmission mechanism of LTP is researched, and LTP transmissionmodel is described completely. Then, a theoretical model of LTP timer isestablished. Finally, the performance is analysed through simulation. This paperwill benefit for the in-depth study of the DTN special functional layer and itsarchitecture.