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Physical Layer

We are working on technologies which are expected to have a strong impact on emerging wireless systems, which include:


Multicarrier Technologies


We have been working on various aspects of OFDM techniques.  We worked on a technique for resource allocation combined with adaptive modulation for an OFDM based access system.  We are also working on application of various OFDM concepts to applications like WLANs and BWA systems.  We have also started some work in MC-CDMA systems.


Space Time Technologies

The activities in this centre with respect to space-time technologies can be categorised into two broad categories as

We are coordinating with our mathematical team on formulation of new codes from design point of view and another team works on engineering codes for performance enhancement.

1. Space-time code designs :

 In this aspect,  we are working on applying algebraic concepts for space-time code design with an effort to achieve the capacity promised by the MIMO channel. We are looking at the mathematical concept of code design, capacity, and the engineering sense of simplicity in decoding and improvement in BER.

2. Space-time code applications :

 In this aspect, people here are involved in applying space-time codes to improve the performance of the wireless channel. We are working in space-time codes for the frequency selective channel and in multi user detection. We are working on providing better schemes and algorithms to improve performance in the wireless environment.


Link Adaptation Technologies

Link adaptation involves the adaptive transmit optimization techniques aimed at maximizing the throughput. We are currently working on the following algorithms:

Our goal is to study the performance of these algorithms using software  simulations and to propose new ones that are computationally less intensive and efficient at the same time. These algorithms are integrated into the (802.11a) simulation environment to test their effectiveness. This can lead to certain potential enhancements to the 802.11a standards.

Another area under link adaptation is in the use of OFDM as multiple access technology. Several algorithms for adaptively allocating subcarriers to users and combining adaptive loading of bits with it are being studied.