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Wireless communications has become a field of enormous scientific and economic interest. Recent success stories include 2G and 3G cellular voice and data services (e.g., GSM and UMTS), wireless local area networks (WiFi/IEEE 802.11x), wireless broadband access (WiMAX/IEEE 802.16x), and digital broad ...

Fourth Generation (4G) wireless communication systems aim to allow peak data rates in the range of 1 Gbps for nomadic access and 100 Mbps for vehicular mobil- ity. 4G aims to support current and emergent multimedia services, such as mobile TV, social networks and gaming, high-definition television a ...

The continuing explosive growth in mobile communication is demanding more spectrally efficient radio access technologies than the prevalent second generation (2G) systems such as GSM to handle just the voice traffic. We are already witnessing high levels of mobile penetration exceeding 70% in some c ...

Having dealt with in-depth analysis of SS#7, GSM and GPRS networks I started to monitor UTRAN interfaces approximately four years ago. Monitoring interfaces means decoding the data captured on the links and analysing how the different data segments and messages are related to each other. In general ...

Telecommunications is today widely understood to mean the electrical means of communicating over a distance. The first form of telecommunications was that of the Telegraph, which was invented quite independently in 1837 by two scientists, Wheatstone and Morse. Telegraphy was on a point-to-point unid ...

Once upon a time, cellular wireless networks provided two basic services: voice telephony and low-rate text messaging. Users in the network were separated by orthogonal multiple access schemes, and cells by generous frequency reuse patterns [1]. Since then, the proliferation of wireless services, fi ...

Two of the major developments reshaping the telecommunications landscape are mobile wireless connectivity and the migration of voice telephone services to IP technology. Those two ideas come together in networks that carry voice services over a wireless LAN (VoWLAN). The purpose of this text is to p ...

Today wireless is becoming the leader in communication choices among users. It is not anymore a backup solution for nomadic travellers but really a newmoodnaturallyusedeverywhereevenwhenthewiredcommunicationsare possible. Many technologies evolve then continuously, changing the telecom- munication w ...

During the past three decades, the world has seen signifi cant changes in the telecom- munications industry. There has been rapid growth in wireless communications, as seen by large expansion in mobile systems. Wireless communications have moved from fi rst-generation (1G) systems primarily focused ...

The advent of modern wireless devices, such as smart phones and MID 1 terminals, has revolutionized the way people think of personal connectivity. Such devices encompass multiple applications ranging from voice and video to high-speed data transfer via wireless networks. The voracious appetite of tw ...