The limited available spectrum of satellite and space communications result in new techniques to reuse the free spectrum. Cognitive Radio (CR) is one of the most promising techniques for such reusing processes. Spectrum sensing (SS) is the core process of cognitive radio which is used to sense the available temporary free bands, holes, of the sensed spectrum.  Many technologies are proposed to achieve both narrow-band and wide-band spectrum sensing. Three paradigms of spectrum sensing applications such as the interweaving approach, the underlay approach and the overlay approach are explained. Many scenarios are proposed to utilize cognitive radio architecture at both standalone and cooperative approaches in satellite communications. The proposed scenario is based on cooperative Sub-Nyquist wideband sensing basis. Nano-computing process is highly required to achieve real-time communication for spectrum sensing in cognitive radio due to the intensive required computations. The Simulation of the proposed scenario showed that it efficiently saves frequency resources, overcomes spectrum underutilization problem, noise and interference problems with an accurate reconstruction.

Many wireless applications are deployed and available to customers via their mobile phones. Variety of these applications and services are based on determination of the current or future location of mobile user. Location based services (LBS) are one of the vital applications which are subdivided into two main categories: economical category and public category. Economic applications include mobile marketing, entertainment and tracking applications. Whereas, emergency cases, safety, traffic management, Muslims' applications and public information applications are sort of public applications. The first part of the paper presents a new proposed system with developed procedure to recreate public and economic applications with high positioning accuracy and good authentication of users' data. The developed system is created to enhance both location based services and network allocation resources within mobile network platform using either normal or GPS supported mobile equipment. The second part of the paper introduces future location prediction of mobile user dependent applications. New algorithm is developed depending on utilizing both intra-cell Movement Pattern algorithm (ICMP) [1] and hybrid uplink time Difference of Arrival and Assisted GPS technique (UTDOA_AGPS) [2]. It has been noticed that ICMP algorithm outperforms other future location prediction algorithms with high precision and within suitable time (less than 220) msec. However, UTDOA_AGPS guarantees high precession of mobile user independent of the surrounding environment. The proposed technique is used to enhance reliability and efficiency of location based services using cellular network platform.

Location based services (LBS) and their applications are one of the most growing services based on wireless communication systems. Future location prediction of mobile user results in a great enhancement of both LBS applications and mobile network performance. Many researches are developed to predict the future location of mobile user. In this paper we proposed a new method, Intra Cell Movement Prediction (ICMP), for mobile user's future location prediction based on mobile network platform to benefit from both intra and inter cell based techniques for network and services enhancement. The proposed method depends on map based intra-cell prediction and utilizes the network database and positioning techniques in extracting user trajectories and movement rules. As a result, the position of the next movement of mobile subscriber can be predicted. The performance of the proposed algorithm is evaluated through computer simulation and compared with that of [1] and [2]. The simulation results indicate that the proposed method is highly efficient for both network and services' improvements as it is used to enhance location based services with satisfactory accuracy, network's resource utilization, reduce the latency in accessing resources and mobility management.

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A hybrid positioning system is merely one in which multiple systems are used for positioning purposes. This virtually always, though not necessarily, includes Global Positioning System (GPS) as it is the only global positioning network currently. Combination of mobile network and GPS positioning techniques provide a higher accuracy of mobile location than positions based on a standalone GPS or mobile network based positions. High accuracy of mobile position is mainly essential for emergency, military and many other location based services such as productivity enhancement, entertainment, position-based advertising, navigation, asset management and geographic information access. Assisted GPS, also known as A-GPS or AGPS, enhances the performance of the standard GPS in devices connected to the cellular network. This paper introduces a new hybrid technique for mobile location determination utilizing Universal Mobile Telecommunication System (UMTS) network, Mobile Station (MS) and GPS positioning characteristics. Different positioning techniques are chosen according to positioning parameters. The minimum required number of UMTS base stations, location measurement units and GPS satellites are calculated in this paper. The required number of GPS satellites is reduced from four satellites to three ones while using three dimension positioning and from three satellites to two ones at two dimension positioning. Moreover, MS receiver main functions including both network and GPS received paths to achieve output assisted data are discussed. In this paper many drawbacks such as indoor positioning, receiver high power consumption, delay in first time to fix position, low position accuracy as well as large number of required satellites and base stations are improved

The limited available spectrum of satellite and space communications result in new techniques to reuse the free spectrum. Cognitive Radio (CR) is one of the most promising techniques for such reusing processes. Spectrum sensing (SS) is the core process of cognitive radio which is used to sense the available temporary free bands, holes, of the sensed spectrum.  Many technologies are proposed to achieve both narrow-band and wide-band spectrum sensing. Three paradigms of spectrum sensing applications such as the interweaving approach, the underlay approach and the overlay approach are explained. Many scenarios are proposed to utilize cognitive radio architecture at both standalone and cooperative approaches in satellite communications. The proposed scenario is based on cooperative Sub-Nyquist wideband sensing basis. Nano-computing process is highly required to achieve real-time communication for spectrum sensing in cognitive radio due to the intensive required computations. The Simulation of the proposed scenario showed that it efficiently saves frequency resources, overcomes spectrum underutilization problem, noise and interference problems with an accurate reconstruction.