Ilias Peteinatos
Start date: 01.03.2012
Email: ilias.peteinatos@brunel.ac.uk
Supervisors: Dr. R. Nilavalan and Prof.Evangelos Kokkinos
MPhil Research Title: WCDMA for Aeronautical Communications
The problem which is developed in the current research concerns Aeronautical communications in connection with the onland systems of management and control for secure flights. Today the contemporary systems of Air Traffic Management and Air Traffic Control have already reached peak conditions in some major airports due to the increasing numbers of flights that have been taking place in the last years.. Some solutions have been suggested in order to deal with this problem we have mentioned above by applying new technologies of greater capacity than the existing VDL (VHF Data Link) mode 2, 3 and 4 systems with systems like the WCDMA (Wideband Code Division Multiple Access). The WCDMA system was regarded as a possible solution due to its high spectrum of efficiency and due to the fact that there was a decade of experience from the development of the onland WCDMA systems worldwide.
A similar problem is the communications that the passengers of the airplanes make with the rest of the world through their mobile phones or through high speed internet. This can also be solved by using WCDMA technology.
Matolak suggested a three dimensional system of circular cell for the air and land communications. In his project he took into consideration the fact that this interference factor is caused by users outside the cell of a CDMA system which consists of an array of uniformly distributed Base Stations and the users who are inside an airplane. It is known that the capacity of the CDMA systems is generally in reverse proportion with the outside cell interference factor. In this project Matolak shows that in the free space of this air-land model the interference factor which is caused by users outside the cell is higher than the similar on land models of transmission (this can be understood because there are no objects that could prevent the transmitting signal) and depends approximately from the logarithm of the radio and the height of the cell.
In 2005 Zhou and his collaborates advanced Matolak’s project trying to investigate the performance in the forward link for the transmission of the data packets and measured the capacity, the throughput and the delay of the system. Their arithmetical results confirmed Matolak’s results, that is, that the performance in Aeronautical systems is worse than their counterpart on land systems and depends on the logarithm of the radio and the height of the cell.
Elnoubi got engaged in expanding the popular system of mobile communications GSM, so that his subscribers would accept and try to make calls while they are being on a plane, having the same SIM card and the same telephone number with the ones they were using with the onland systems. In that project he made the necessary alternations in the structure of the GSM and suggested an area of accommodation in the space, of multiply layers, namely he devided the space in three coaxial circular cells. He measured the capacity for the suggested GMS system and he compared it with the capacity for CDMA and FDMA systems. The conclusion he reached is that his suggested system has greater capacity , if we assume that we have the same bit rate per user in all the systems.
In 2011 Smida studied the air-to-ground cellular systems with no frequency reuse. An analysis of the inter-cell interference under idealized assumptions: 3D hexagonal cell planning, a line of sight channel model with no shadowing and idealized antenna patterns was provided. Very accurate closed form bounds for the interference were given under these idealized assumptions.
