|
Next Generation Networks Group |
|
Introduction |
|
The Next Generation
Networks (NGN) is an active and indispensable research group of Centre of Advanced
Studies in Telecommunication (CAST). The primary motivation of the group is research
and development for the B3G technologies. Its perseverance is to present with novel
architecture and protocols for the advancement and implementation of wireless access networks. NGN is also very actively involved in the collaboration ventures with
national and international universities and research centers. |
|
The telecommunication industry is also
changing, with a demand for a greater range of services, such as video conferences,
or applications with multimedia contents. The increased reliance on computer networking
and the
Internet has resulted in a wider demand for connectivity to be provided "any where, any time", leading to a rise in the requirements for higher capacity
and high reliability broadband wireless telecommunication systems. |
Members
- Ms. Beenish Niaz
- Ms.Shama Noreen
-
Mr. Muhammad Adnan khan
- Mr. Taimur Shahzad
|
|
Current Research Activities |
•
Implementation of WiMAX Testbed
Mr. Ali Imran, Mr. Wajid Mumtaz, Mr. Talha Faiz-ur-Rehman and Ms. Beenish Niaz |
|
WiMAX is a short name for Worldwide
Interoperability of Microwave Access. WiMAX is described in IEEE 802.16 Wireless
Metropolitan Area Network (MAN) standard.NGN is extensively involved in the research
and development of WiMax testbed. The testbed will be implemented according to the
WiMAX standard document. To facilitate the design process, modular approach is used
for testbed development. Following diagram explains the implementation at block
level.
|
 |
|
The baseband processing is implemented
at software level in the first phase of the project. The second phase consist the
hardware
implementation. ISM band (2.45GHz) will be used for RF section. The RF
section consists the off the shelf modules.
|
•WiMAX with Adaptive modulation
Dr. Naeem Zafar
Azeemi, Mr. Talha Faiz-ur-Rehman and Mr. Arshad Abbas |
|
WiMAX supports a Varity of modulation
and coding schemes and allows for the scheme to change on a burst-by-burst basis
per link. Channel quality feed-back indicator is used to check the down link quality.
For the uplink, the channel quality is estimated by the base station using the
received signal. Using this information the base station scheduler will assign a modulation
and coding scheme that will maximize the throughput. |
•
Performance enhancement of OFDM using MIMO techniques
Dr. Naeem Zafer Azeemi, Mr.
Wajid Mumtaz and Mr. Shahbaz shaukat |
|
A new approach to the problem of enhancing
the performance of a broadband OFDM based system using MIMO techniques. The evaluated
MIMO techniques are VBLAST, STBC and by sub carrier selection. As MIMO systems are
useful for the increased data rate using Space Division Multiplexing. The combination
of the through put enhancement of SDM with the robustness of OFDM against frequency
selective fading cost by severe multipath scattering and narrowband interference
is regarded as promising bases of future (indoor) high data rate future communication
systems. |
•
Physical Layer Implementation of WiMax (fixed) using OFDM
Dr. Naeem Zafer
Azeemi, Mr. Wajid Mumtaz and Mr. Muhammad Zia Qammar |
|
IEEE 802.16-2004 is a standardized
technology for supporting broadband and wireless communication with fixed access.
The WiMax physical layer is based on orthogonal frequency division multiplexing.
OFDM is the transmission scheme of choice to enable high speed data, video and multimedia
communication and is used by a variety of commercial broadband systems, including DSL, Wi-Fi, Digital Video Broadcast-Handheld (DVB-H), MediaFLO, besides WiMax. OFDM
is an elegant and efficient scheme for high data rate transmission in a non line
of sight or mltipath radio environment. |
•
Software defined radio for WCDMA and WiFi (IEEE 802.11g)
Dr. Naeem Zafer Azeemi, Mr. Talha Faiz ur Rahman, Mr Ata-ul-Mannan and Mr. Asfand |
|
In this project, the configuration
and key technologies of the newly developed small-size software radio terminal are
introduced. The terminal consists of a common platform that includes an original
field programmable gate array (FPGA) board with four FPGAs, a CPU board that has
two CPUs and is operated by µITRON, and RF boards with open interface. Users have only to prepare software for FPGAs and CPUs that can configure mobile communication
systems. In addition, the common platform has control software that can change several
communication systems as users like by using several algorithms based on certain
conditions. On the common platform, the software of W-CDMA and IEEE802.11a that
realizes physical layer, data-link layer, and network (TCP/IP) layer has been established.
Users can change communication systems by using programmed control software that
receives users’ request, propagation characteristics, data error, and so on from
RF board and FPGA board. |