فتح مکہ میں آنحضرت ﷺ کی حربی حکمت عملی

This article encompassed the Holy Prophet's (ﷺ) best war strategy in the conquest of Makkah and its relevance to the Modern society. The purpose of this article was to highlight the war strategy of Holy Prophet (ﷺ) in the conquest of Makkah. His strategy provided the noble example for warfare in modern world. The method used for research was historical. The review of literature revealed that the war, humanity for love the showed (صلى الله عليه وسلم) Muhammad Prophet of strategies concern for the safety of the lives and avoided bloodshed as far as possible. Because of his noble strategies, Makkan tribes surrendered without any resistance in front of the army of Islam. Consequently, (صلى الله عليه وسلم) Prophet Holy the and idolatry from freed became Makkah conquered the last and the most solid stronghold of the enemy. In Modern era, Muslim faced so many war problems. Through the war war the learn can commanders military, (صلى الله عليه وسلم) Prophet Holy of strategies ethics and overcome their problems. It is recommended to Muslim army that they should take guidance from the war strategy of Prophet pressure psychological putting by enemy defeat and (صلى الله عليه وسلم) Muhammad upon them.

Evaluation and Enhancement of Mac Protocols for Efficient Spectrum Management and Sharing in Cognitive Radio Networks

Cognitiveradionetworks(CRNs)havegainedatremendousinterestintheresearch community, as they tend to solve the existing and future issues of frequency spectrum scarcity by exploiting the spectrum holes in underutilized licensed and unlicensed frequency bands, thereby, improving the spectrum utilization. The number of channels in a Cognitive Radio Network (CRN) always varies with time and location as compared to legacy wireless networks with fixed number of radio channels. This variability of available channels in cognitive radio networks has brought new design challenges in MediumAccessControl(MAC)protocolsandhasledtotheneedformostefficientand reliable MAC protocols in a CRN that can sustain under variable network conditions. Thesharingofdiscoveredspectrumholesamongthecontendingsecondaryusers(SUs) increases the overall spectrum utilization; however, the utilization of these discovered spectrum holes within the CRN depends on the access mechanism of SUs. In random access, waste of these spectrum holes would occur due to collisions and un-attempted slots by SUs. Therefore, optimal use of these discovered holes with minimum or no waste is desirable in an efficient CRN. A self- organizing collision-free MAC protocol isproposedforthedistributedCRNthatismoreefficientinspectrumsharingbyavoiding collisions and maximally utilizing un-attempted slots during access phase, thus increasing the spectrum utilization and throughput. This is achieved by organizing and queuing the active SUs through a timer value and directing them in an orderly fashion to use the discovered holes. Finding holes from the underutilized portion of spectrum at varying times and locations is the most important function in CRNs. This requires efficient sensing policy at the MAC layer that can discover more idle channels in minimal time. Spectrum sensing policies for searching idle channels from the underutilized primary band can significantly affect the performance of SUs in terms of throughput, reliability and en ergy efficiency. The sensing policy depends on the channel sensing order that decides how SUs sense the primary user band in minimal period of time. A cooperative parallel sensing scheme with sequential channel selection order is proposed as part of the MAC protocol, which can discover all the free channels in the primary user band in minimal time. The proposed scheme has been analyzed for the number of channels sensedandthenumberofidlechannelsdiscovered. Furthermore,energyefficiencyand throughput of the proposed scheme have also been evaluated. The results show considerable improvement for the proposed scheme as compared to the random channel spectrum sensing schemes prevalent in adhoc CRNs. The work in this thesis has aimed to improve spectrum management by adopting new spectrum sensing policies and improvingspectrumsharingbyself-organizingthecognitiveusersforcollisionfreeaccess in adhoc CRN MAC protocols.