23-04-2012, 11:43 AM
4G mobile communications
[attachment=20580]
INTRODUCTION:
The first operational cellular communication system was deployed in the Norway in 1981 and was followed by similar systems in the US and UK. These first generation systems provided voice transmissions by using frequencies around 900 MHz and analogue modulation.
The second generation (2G) of the wireless mobile network was based on low-band digital data signaling. The most popular 2G wireless technology is known as Global Systems for Mobile Communications (GSM). The first GSM systems used a 25MHz frequency spectrum in the 900MHz band.
Migrating to 4G:
The fact that 4G mobile networks intend to integrate almost every wireless standard already in use, enabling its simultaneous use and interconnection poses many questions not yet answered. The research areas that present key challenges to migrate current systems to 4G are many but can be summarized in the following: Mobile Station, System and Service. To be able to use 4G mobile networks a new type of mobile terminals must be conceived. The terminals to be adopted must adapt seamless to multiple wireless networks, each with different protocols and technologies. Auto reconfiguration will also be needed so that terminals can adapt to the different services available. This adaptation may imply that it must download automatically configuration software from networks in range. Moreover terminals must be able to choose from all the available wireless networks the one to use with a specific service.
GENERIC MIMO AND OFDM:
Increasing demand for high performance 4G broadband wireless mobile calls for use of multiple antennas at both base station and subscriber ends. Multiple Antenna technologies enable high capacities suited for Internet and multimedia services and also dramatically increase range and reliability. This design is motivated by the growing demand for broadband wireless Internet access. The challenge for wireless broadband access lies in providing a comparable quality of service for similar cost as competing wire line technologies.
Conclusion:
In this paper we present the evolution of mobile communications through all its generations. From the initial speech vocation to an IP-based data network, several steps were made. From the analog voice centric first generation to the digital second generation, the goal was to enhance the voice experience of a user, by improving the quality of the communication while using more efficiently the installed capacity.
[attachment=20580]
INTRODUCTION:
The first operational cellular communication system was deployed in the Norway in 1981 and was followed by similar systems in the US and UK. These first generation systems provided voice transmissions by using frequencies around 900 MHz and analogue modulation.
The second generation (2G) of the wireless mobile network was based on low-band digital data signaling. The most popular 2G wireless technology is known as Global Systems for Mobile Communications (GSM). The first GSM systems used a 25MHz frequency spectrum in the 900MHz band.
Migrating to 4G:
The fact that 4G mobile networks intend to integrate almost every wireless standard already in use, enabling its simultaneous use and interconnection poses many questions not yet answered. The research areas that present key challenges to migrate current systems to 4G are many but can be summarized in the following: Mobile Station, System and Service. To be able to use 4G mobile networks a new type of mobile terminals must be conceived. The terminals to be adopted must adapt seamless to multiple wireless networks, each with different protocols and technologies. Auto reconfiguration will also be needed so that terminals can adapt to the different services available. This adaptation may imply that it must download automatically configuration software from networks in range. Moreover terminals must be able to choose from all the available wireless networks the one to use with a specific service.
GENERIC MIMO AND OFDM:
Increasing demand for high performance 4G broadband wireless mobile calls for use of multiple antennas at both base station and subscriber ends. Multiple Antenna technologies enable high capacities suited for Internet and multimedia services and also dramatically increase range and reliability. This design is motivated by the growing demand for broadband wireless Internet access. The challenge for wireless broadband access lies in providing a comparable quality of service for similar cost as competing wire line technologies.
Conclusion:
In this paper we present the evolution of mobile communications through all its generations. From the initial speech vocation to an IP-based data network, several steps were made. From the analog voice centric first generation to the digital second generation, the goal was to enhance the voice experience of a user, by improving the quality of the communication while using more efficiently the installed capacity.