Low bit rate satellite link for emergency communications

Abstract

This study inserts itself within the framework of the first phase of a post-disaster emergency situation. The purpose here is to propose and study a solution allowing to establish very quickly a minimal low bit rate satellite link in Ku/Ka or Q/V band, while using the available resources of the satellite, a singleuser ground terminal with a low transmission power, a small diameter antenna, and a dedicated Tx/Rx system, characterized by an electric consumption which shall be as low as possible (battery or solar panels). The transmission channel is modeled within the Juzzle open source environment software, with an adaptive strategy based on the DVB-S2 adaptive modulation and coding (ACM) scheme. Keywords-satellite communications, low bit rate, emergency, Ku/Ka/Q/V bands, rain attenuation, channel fading, DVB-S2, ACM, spread spectrum, VoIP, SMS, Juzzle.

Hybrid Satellite - Wireless Sensor Networks Architecture for Telemedicine Applications in the Context of Emergency Satellite Communications in Ku/Ka/Q/V Bands

“…The data to be transmitted is characterized mainly in terms of bit rate, overhead, error rates (BER [Bit Error Rate], or PER [Packet Error Rate]), delay, jitter, average and maximum packet sizes. In the following, two types of services are considered and their salient QoS features will be presented along with a number of constraints from higher layer protocols [20][21][22]: real-time applications; data-like loss-sensitive, but not or very little delaysensitive applications. [31].…”

“…Moreover, the time interval between the sending of an SMS and its reception by the receiver must be between 6 and 8 seconds in average, given that actually 98% of sent SMSs are successfully delivered by a mobile user to a fixed network within a 5 sec time period, according to some telecom operators [4,5]. Since the integrity of SMS messages is 100%, it is obvious that SMSs are well fitted to telemedicine communications, especially in emergency situations [20][21][22], where there is a need to transmit an alarm.…”

“…The proposed system architecture and scenario were as follows [21]: the emergency mission signals are superimposed with those of the primary system characterized by a star topology, a classic multibeam, multicarrier, broadband bent-pipe satellite operating either in Ku/Ka or Q/V-band, and with a 120-MHz transponder. Thus a dedicated channel for the emergency mission is not required.…”

Design and Simulation of a DVB-S2-like Adaptive Air interface Designed for Low Bit Rate Emergency Communications Satellite Link in Ku/Ka/Q/V Bands

“…System architecture, scenario, and traffic characterization 2.1 System architecture and scenario The proposed system architecture and scenario are as follows (Pech et al, 2008): the emergency mission signals are superimposed with those of the primary system characterized by a star topology, a classic multibeam, multicarrier, broadband bent-pipe satellite operating either in Ku/Ka or Q/V-bands, and with a 120-MHz transponder (cf. Fig.…”

“…Thus, it is an absolute priority, in order to manage a situation of post-disaster, to restore the communications infrastructure. Three distinct and consecutive phases can be distinguished (Pech et al, 2008):…”