Category Archives: Industry News

Broadband satellite communication networks, operating at Ka band and above, play a vital role in today’s worldwide telecommunication infrastructure. The problem, however, is that rain can be the most dominant impairment factor for radio propagation above 10 GHz. This paper studies bandwidth and time slot allocation problem for rain faded DVB-RCS satellite networks. We investigate how using finer rain granularity can improve bandwidth utilization in DVB-RCS return links.

Al-Mosawi, M., Khusainov, R. and Gremont, B. “Rain granularity effects on bandwidth demand for faded DVB-RCS systems” Wiley, 25 August 2014. Web. 26 August 2014.

http://onlinelibrary.wiley.com/doi/10.1002/sat.1085/abstract

Convergence is one of the most important challenges for Next Generation Networks (NGN). This includes service convergence as well as fixed-mobile convergence. The integration of satellite telecommunication system into NGN is a key to increasing the coverage of future networks and opening satellite access networks to a wider range of terrestrial solutions. Digital Video Broadcast (DVB) Return Channel via Satellite system (DVB-RCS) and its evolution (DVB-RCS2) are widely used European standards that are specified for broadband satellite systems using dynamic capacity assignment and multifrequency TDMA.

Baudoin C., Gineste M., Emmanuel C., Gelard P., and Bernard J. “Dynamic satellite system QoS architecture integrated with IP Multimedia Subsystem core network” Wiley, 30 July 2014. Web. 30 July 2014.

http://onlinelibrary.wiley.com/doi/10.1002/sat.1084/abstract

The campaign to collect rain attenuation data on terrestrial links had commenced in Malaysian tropical climates for almost two decades. The terrestrial data so far collected have been greatly utilized to derive useful statistics for various microwave applications, such as frequency scaling, rain rate conversion factor, 1-min rain rate contour maps, wet antenna losses, and fade slope duration analysis. However, there is still severe scarcity of rain attenuation data on earth–space links in Malaysia. The results of the 2-year measurement (January 2009–December 2010) of rain rates and rain-induced attenuation in vertically polarized signals propagating at 10.982 GHz have been presented in this paper. The rain attenuation over the link path was measured at Islamic International University Malaysia and compared with ITU-R P.618-10 and Crane global models in this paper.

Abdulrahman, Y., Rahman, T. A., Islam, R. M., Olufeagba, B. J. and Chebil, J. “Comparison of measured rain attenuation in the 10.982-GHz band with predictions and sensitivity analysis” Wiley, 22 June 2014. Web. 23 June 2014.

http://onlinelibrary.wiley.com/doi/10.1002/sat.1082/abstract

Satellite transmissions are prone to both unintentional and intentional RF interference. Such interference has significant impact on the reliability of packet transmissions. In this paper, we make preliminary steps at exploiting the sensing capabilities of cognitive radios for reliable satellite communications. We propose the use of dynamically adjusted frequency hopping (FH) sequences for satellite transmissions. Such sequences are more robust against targeted interference than fixed FH sequences. In our design, the FH sequence is adjusted according to the outcome of out-of-band proactive sensing, carried out by a cognitive radio module that resides in the receiver of the satellite link. Our design, called out-of-band sensing-based dynamic FH, is first analyzed using a discrete-time Markov chain (DTMC) framework.

Abdel-Rahman, M. J., Krunz, M. and Erwin, R. “Exploiting cognitive radios for reliable satellite communications” Wiley, 22 June 2014. Web. 23 June 2014.

http://onlinelibrary.wiley.com/doi/10.1002/sat.1083/abstract

The pre-emption procedure is an important part of the radio resource management when dealing with the emergency traffic. It allows resources to be allocated to higher priority connections by pre-empting lower priority connections. The provision of the pre-emption mechanism becomes much more important in the case of satellite systems such as the Inmarsat Broadband Global Area Network system, which aids in providing the communication during a catastrophe. This paper focuses on the pre-emption framework for a Universal Mobile Telecommunications System-based satellite systems. Three algorithms have been proposed, Greedy, SubSetSum and Fuzzy pre-emption algorithm. Extensive simulations are carried out for the three algorithms, and their performances are compared against each other.

Pillai, A., Hu Y.-F., and Halliwell R. “A pre-emption framework for UMTS compatible satellite system supporting multimedia traffic” Wiley, 10 June 2014. Web. 10 June 2014.

http://onlinelibrary.wiley.com/doi/10.1002/sat.1080/abstract