مقاصد الإسلام في تحقيق السلام

This research focused on highlighting the purposes of Islam in achieving peace. This paper explains how Islam is the religion of peace and security for the worlds. Its provisions, legislations and purposes ensured all mankind the right to security and security of all kinds: Psychological security, financial security, social security and other types of security which ensure that humanity can live in peace. This is without any kind of these securities being subjected to any slight aggression, sabotage, deprivation or injustice, and if any of that happens then it would be a manifestation of violence and terrorism that is neither accepted nor recognized by Islam which is the religion of peace. The research has shown that Islam has preceded all international laws and norms with respect to the legalization of human rights in peace and war times alike and the sanctioning of those who violate them in this world and in the Hereafter. This is done with supporting evidence from the Quran, the Sunnah, the work of the leaders of Muslim Ummah throughout the Islamic centuries, and the testimonies of non-Muslims who have lived the mercy of Islam and come to know the observance of Islam of human rights. The aims of the research are: To demonstrate the legitimate purposes that Islam has brought to preserve human dignity and security. To show the precedence and superiority of Islamic law in the field of human rights care. To highlight the rich Islamic heritage of human values and civilization through the rules of humanitarian dealing in Islamic jurisprudence in war and peace, and the contributions of the purposes of the Sharia in the development of rules for the preservation of rights and freedoms.

Symbol Detection Techniques in a Spatial Multiplexing System

Significant performance gains are achievable in wireless communication systems using a Multi-Input Multi-Output (MIMO) communications system employing multiple antennas. This architecture is suitable for higher data rate multimedia communications. One of the challenges in building a MIMO system is the tremendous processing power required at the receiver side. MIMO Symbol detection involves detecting symbol from a complex signal at the receiver. The existing MIMO detection techniques can be broadly divided into linear, non-linear and exact detection methods. Linear methods like Zero-Forcing offer low complexity with degraded Bit Error Rate (BER) performance as compared to non-linear methods like VBLAST. Non-linear detectors are computationaly not very expansive with acceptable performance. Exact solutions like Sphere Decoder provide optimal performance however it suffers from exponentional complexity under certain conditions. The focus in the early part of this thesis is on non-linear approximate MIMO detectors and an effort has been made to develop a low complexity near-optimal MIMO detector. Computational Swarm Intelligence based Meta-heuristics are applied for Symbol detection in a MIMO system. This approach is particularly attractive as Swarm Intelligence (SI) is well suited for physically realizable, real-time applications, where low complexity and fast convergence is of absolute importance. Application of Particle Swarm Optimization (PSO) and Ant Colony Optimization (ACO) algorithms is studied. While an optimal Maximum Likelihood (ML) detection using an exhaustive search method is prohibitively complex, we show that the Swarm Intelligence optimized MIMO detection algorithms gives near-optimal Bit Error Rate (BER) performance in fewer iterations, thereby reducing the ML computational complexity significantly. In this thesis novel non-conventional MIMO detection approaches based on Swarm-Intelligence techniques have been presented. An effective and practical way to enhance the capacity of MIMO wireless channels is to employ space-time (ST) coding. Space-time block coding (STBC) is a transmit diversity technique in which the data stream to be transmitted is encoded in blocks, which are distributed among multiple antennas and across time. Alamouti’s simple STBC scheme for viwireless communication systems uses two transmit antennas and linear maximum-likelihood (ML) decoder. This system was generalized by Tarokh to an arbitrary number of transmit antennas by applying the theory of orthogonal designs. In the later part of this thesis a simple multi-step constellation reduction technique based decoding algorithm that further simplifies the linear ML detection in Orthogonal Space-Time Block Coded systems is proposed. This approach reduces the computational complexity of these schemes while presenting the ML performance. In addition, Spatial Multiplexing systems using Orthogonal Walsh codes are also studied. This approach has a potential to reduce the search space to allow efficient symbols detection in Spatial Multiplexing systems.