satellite mobile radio systems

Top PDF satellite mobile radio systems:

CMC ICT3207 Call Flow

CMC ICT3207 Call Flow

Introduction to Mobile Communication: history and evolution of mobile radio systems, types of mobile wireless services/systems - cellular, WLL, paging, satellite systems, standards, and future trends in personal wireless systems. Cellular concepts and system design fundamentals/frequency management and channel Assignment: Cellular concept and frequency reuse, Multiple Access Schemes, fixed Channel assignment, non-fixed channel assignment and handoff. Interference and system capacity, Trunking and Erlang capacity calculations. Mobile radio propagation Radio wave propagation issues in personal wireless systems, Propagation models, Multipath fading and base band impulse response models, Parameters of mobile multipath channels, Antenna systems in mobile radio.
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Future mobile satellite systems: Issues in timing synchronisation and resource allocation techniques

Future mobile satellite systems: Issues in timing synchronisation and resource allocation techniques

per timeslot than GSM, which attains a maximum d ata rate of 9.6 kbps as discussed earlier. Considering also the fact th a t several timeslots can be used by the same user for data transmission, one can conclude th a t very high d a ta rates can be achieved with GPRS. There is of course a trade off between the high coding rates and the total delay caused by the retransmissions of erroneous blocks, and the scheme th at provides the most balanced solution must be adopted for each different radio en­ vironment. USFs provide the user with information th a t has to be decoded a lot faster than the rest of the block in order to enable him /her to prepare the data transmission in the next block time. Therefore, in schemes CS2-CS4 a 12-bit USF codeword is created. In schemes CS2 and CSS a 6-bit USF block is created, and then convolutional coding is applied to the whole block without puncturing the first 12 bits.
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State modelling of the land mobile propagation channel for dual satellite systems

State modelling of the land mobile propagation channel for dual satellite systems

Early studies on multi-satellite transmission were carried out in 1992. Based on circular scans of fisheye-camera pictures in different environments an empirical model was developed describing the correlation coefficient between two satellite signals depending on their azimuth separation [6]. In 1996 a statistical channel model for two correlated satellites based on first-order Markov chains was developed [7]. The state sequence generation is based on state transition probabilities of two independent satel- lites. Both satellites are combined by a state correlation parameter which can be taken from empirical models. Due to its simplicity this modelling approach is frequently used today. However, first-order Markov chains have limi- tations in state duration modelling, as their state durations follow an exponential distribution. Studies in [8-10] found that this condition does not hold for the LMS channel. Nevertheless, a correct state duration modelling is of high interest for the optimal configuration of physical layer and link layer parameters for modern broadcasting stan- dards with long time interleaving (e.g. for physical layer interleaver size, link layer protection time). Therefore, different concepts improving the state duration modelling were introduced: semi-Markov chains [10] and dynamic Markov chains [9]. For these approaches some exemplary parameters for the single-satellite reception are pub- lished. However, an intense study for multi-satellite state duration modelling and a corresponding channel model including parameters for different environments and orbital positions does not exist so far. In this sense, a new channel model for two or more satellites was developed in the context of the project MiLADY (Mobile satellite channeL with Angle DiversitY) [11]. This project covered two measurement campaigns in the U.S. and in Europe: In the first campaign the power levels of the Satellite Digital Audio Radio Services (SDARS) satellites (S-Band) were recorded synchronously with a sample rate of 2.1 kHz. The signals allow to study slow and fast fading effects in combination with angle diversity for a limited set of elevation and azimuth angle combinations. A second measurement campaign was carried out in the area of Erlangen in Germany to record the carrier-to-noise spec- tral density ratio (C/N 0 ) from Global Navigation Satellite
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Resolution and Parametric Depiction of Space Time Block Code Over Multiple Fading Channels Rashid Equbal 1, Prof. Nikhil Ranjan2 , Dr. Manish Jain 3

Resolution and Parametric Depiction of Space Time Block Code Over Multiple Fading Channels Rashid Equbal 1, Prof. Nikhil Ranjan2 , Dr. Manish Jain 3

Space-Time Codes (STCs) have been implemented in cellular communications as well as in wireless local area networks. Space time coding is performed in both spatial and temporal domain introducing redundancy between signals transmitted from various antennas at various time periods. It can achieve transmit diversity and antenna gain over spatially uncoded systems without sacrificing bandwidth. The research on STC focuses on improving the system performance by employing extra transmit antennas. In general, the design of STC amounts to finding transmit matrices that satisfy certain optimality criteria. Constructing STC, researcher have to trade-off between three goals: simple decoding, minimizing the error probabilty, and maximizing the information rate. The essential question is: How can we maximize the transmitted date rate using a simple coding and decoding algorithm at the same time as the bit error probability is minimized
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Remote explorations. We re there with you. ENERGYCOMMS

Remote explorations. We re there with you. ENERGYCOMMS

Wherever the search for resources takes your team, you can depend on Thuraya EnergyComms to significantly boost effectiveness in the field, by enabling afford- able voice calls, fax, SMS and Internet services. For full business connectivity, you can use Thuraya to support SCADA monitoring, security feeds, field-to-field co-ordination, location and geological reporting, as well as remote asset tracking. Whatever the requirement, Thuraya’s satellite network enables your employees to stay connected with their colleagues and families, and ensures your production keeps up with global demand.
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The IPTS Report No  1, February 1996

The IPTS Report No 1, February 1996

Third generation mobile communication systems aim to integrate all the different services and technologies mentioned above cordless, PCS, cellular, satellite and provide a competitive se[r]

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Mobile Phone Antenna Performance 2013

Mobile Phone Antenna Performance 2013

The conducted measurements show a very good performance and a rather similar performance of the measured phones. This is as expected, since the radio chips used are of a few types and all comply fully with the required performance. This shows very clearly that only the antenna cause the phones to have very different coverage performance.

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Single  and Multi Carrier DS CDMA: Multi USer Detection, Space Time Spreading, Synchronisation, Standards and Networking

Single and Multi Carrier DS CDMA: Multi USer Detection, Space Time Spreading, Synchronisation, Standards and Networking

Lajos Hanzo received his degree in electronics in 1976 and his doc- torate in 1983. During his career in telecommunications he has held various research and academic posts in Hungary, Germany and the UK. Since 1986 he has been with the Department of Electronics and Com- puter Science, University of Southampton, UK, where he holds the chair in telecommunications. He has co-authored 10 books on mobile radio communications, published about 400 research papers, organised and chaired conference sessions, presented overview lectures and has been awarded a number of distinctions. Currently he heads an academic re- search team, working on a range of research projects in the field of wireless multimedia com- munications sponsored by industry, the Engineering and Physical Sciences Research Council (EPSRC) UK, the European IST Programme and the Mobile Virtual Centre of Excellence (VCE), UK. He is an enthusiastic supporter of industrial and academic liaison and he of- fers a range of industrial courses. He is also an IEEE Distinguished Lecturer. For further information on research in progress and associated publications please refer to http://www- mobile.ecs.soton.ac.uk
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An efficient and secure anonymous authentication scheme for mobile satellite communication systems

An efficient and secure anonymous authentication scheme for mobile satellite communication systems

communication systems. Compared with the related schemes, the proposed scheme achieves the following three main advantages: (1) It is just based on a secure one-way hash function for avoiding complex computations for both mobile users and network control center (NCC), (2) it does not require sensitive verification table which may cause NCC to become an attractive target for numerous attacks (e.g., insertion attacks and stolen-verifier attacks), and (3) it provides higher security level (e.g., secure mutual authentication and key establishment, confidential communication, user ’ s privacy, simple key management, and session key independence). As a result, the proposed scheme is very suitable for lightweight-device environments because of very low computation overload on the part of both mobile user and NCC.
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INTEGRATED TELECOMMUNICATIONS CONTROL SYSTEM (GETI) Mod. S

INTEGRATED TELECOMMUNICATIONS CONTROL SYSTEM (GETI) Mod. S

The realized mobile unit has been used for the first time in operating activities following the “Youth Meeting” with the Pope in September 2007 in Loreto. The system has ensured, 24h to 24h, the radio and telephone links with all the operational centers involved in the control and safety of the meeting. The Unit attracted great interest and appreciation from other Italian Department for the full operational autonomy and the immediacy of radio and wire communications implemented with the transponder. We report some pictures of meeting’s place:

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Rain attenuation estimated from radar measurements for mobile satellite systems and based mobile unit terminals

Rain attenuation estimated from radar measurements for mobile satellite systems and based mobile unit terminals

Observation is done by draw a line for every 2 0 of azimuth angle from radar station to mobile unit. Calculate altitude, h and from there find elevation angle for every azimuthal scanning. Observed rain attenuation path for every 1 km of volumetric inside a range bin from radar station. Observation is done under the rain height or melting layer is about 5 km. In this project n of range bin that rainfall were intersecting must be also considered.

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Klystron and Reflex Amplifier.pdf

Klystron and Reflex Amplifier.pdf

The voltage on the reflector must be adjusted so that the bunching is at a maximum as the electron beam re- enters the resonant cavity, thus ensuring a maximum of energy is transferred [r]

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Diodes.pdf

Diodes.pdf

A tunnel diode, also called an Esaki diode, is a specialty diode that functions by means of a strange effect of quantum mechanics, called "tunneling." This effect gives them an[r]

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LEOS. Hearings on non-geostationary mobile satellite systems (low earth orbiting satellite systems: LEOS), Brussels, 9-10 November 1992

LEOS. Hearings on non-geostationary mobile satellite systems (low earth orbiting satellite systems: LEOS), Brussels, 9-10 November 1992

• development and implementation of the system: technology and intellectual property rights IPRs, procurement and sourcing, launching plans; • frequency allocation and frequency sharing,[r]

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Temperature Effect on the Tropospheric Radio Signal Strength for UHF Band at Terengganu, Malaysia

Temperature Effect on the Tropospheric Radio Signal Strength for UHF Band at Terengganu, Malaysia

The methodology is as outlined in Fig. 1. Firstly, all equipment was prepared to conduct an observation. According to [11], site selection is very important for decision makers to propose where to determine the observation site. It was decided to perform the data collection at KUSZA Observatory, East Coast Environmental Research Institute (ESERI), UniSZA which is situated in Merang, Terengganu. KUSZA Observatory is located near the beach at 5 ° 32' 10" N and 102 ° 56' 55" E on top of the hill with low population density and tropical wet climate. Both RFI pattern and temperature were observed on 26th of August 2015. Statistical analysis was performed from 3600 data to determine the correlation between temperature change and the radio signal pattern.
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Department of Electrical and Electronic Information Engineering

Department of Electrical and Electronic Information Engineering

Our research interests are focused on smart sensing systems based on CMOS/MEMS technology. Multimodal sensing systems integrated with different kind of sensors such as physical sensors, chemical sensors, and biosensors, attract attention as a key element of new generation society based on IoT and big data analysis. This concept is proposed in the 5th Science and Technology Basic Plan of Japan as “Society 5.0”. In our laboratory, design and fabrication technologies of the multi-modal sensors are studied. Novel application of sensors in the harsh environment that can be realized using robust packaging technology is also investigated.
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Simulation of WCDMA radio over fiber technology

Simulation of WCDMA radio over fiber technology

In the standardization forum, WCDMA technology has emerged as the most widely adopted third generation air interface. Its specification has been created in 3GPP (the 3 rd Generation Partnership Project), which is the joint standardization project of the standardization bodies from Europe, Japan, Korea, the USA and China. Within 3GPP, WCDMA is called UTRA (Universal Terrestrial Radio Access), FDD (Frequency Division Duplex) and TDD (Time Division Duplex). The name of WCDMA being used to cover both FDD and TDD operation.

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Advanced radio propagation methodology for the optimisation of resources in mobile systems

Advanced radio propagation methodology for the optimisation of resources in mobile systems

Mandarini, University of Rome 'La Sapienza', Italy... Parallel Advanced Time Division Multiple Access Modems for UMTS.[r]

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Importance of Microwave Antenna in Communication System

Importance of Microwave Antenna in Communication System

Backbone or back haul systems have been built for mobile operators who want to be independent from Telcos and fixed wire operators. It saves cost for leasing a fixed line and allows a simple upgrade of the network if higher capacity is required. In addition traditional and new telcom's, utilities as well as broadcast organizations are upgrading their networks to offer higher capacities to clients or to upgrade their system from analogue to digital service. Backbone systems usually use large size antennas in frequency bands below 10 GHz.
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Design, Analysis, Implementation and Evaluation of Real-time Opportunistic Spectrum Access in Cloud-based Cognitive Radio Networks

Design, Analysis, Implementation and Evaluation of Real-time Opportunistic Spectrum Access in Cloud-based Cognitive Radio Networks

Communication systems have introduced plethora of technological advancements in infor- mation sharing. Every innovation in communication has propounded yet another revolu- tionary idea in the field of technology. Similarly, the birth of Internet can be accredited to contributions from communication systems. With the advent of Internet, many other technologies in communications are born. One such technologies is wireless-local-area- network (Wi-Fi) [1]. And not just Wi-Fi, but cellular technologies have evolved as well. These profound technologies use wireless media to transmit information to longer distances using electromagnetic waves and are entitled to mathematical models for wave-propagation proposed by many renowned scientists and mathematicians such as Maxwell, Hertz, Mar- coni, Tesla, and many more [2].
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