Mini Vasudevan

An automatic process for growth planning in a wireless network

The last few years have seen a tremendous demand for wireless services. Service providers have to accommodate this rapid growth on their existing networks as well as make plans for new networks. Therefore, there is a need for a cell planning tool incorporating optimization techniques to assist RF engineers for initial as well as the future growth planning. This paper proposes an innovative approach for automatic cell site growth planning in an existing network. The new approach replaces the current tedious and inaccurate manual process, simplifies planning, and also reduces operational costs. In addition, this process makes use of powerful optimization algorithms, which can guarantee a near optimum solution.

Interference immunity and spectral reuse in PCS systems

The advent of PCS has necessitated systems employing different bandwidths, modulation techniques and access schemes to coexist. In this scenario, the conventional method for analyzing intersystem interference, considering only the relative power levels of the carrier and the interferer, is insufficient to determine the performance degradation. This paper analyzes the interference effects on analog phase modulated systems due to a QPSK modulated digital interferer by determining the interference spectral density at baseband as a function of the RF carrier-to-interference ratio. This density is then compared with that due to an equivalent analog interferer. Interfering signals with the same power but employing different modulation schemes and occupying different bandwidths are shown to cause vastly different performance degradation at baseband for the victim signal. This methodology is more accurate in determining the carrier-to-interference objective and serves as an improved design tool for optimizing bandwidth in various scenarios of spectral reuse involving dissimilar systems.

A novel frequency transition scheme for capacity enhancement in a cellular radio system

This paper presents a smooth transition scheme for frequency planning when capacity enhancement is envisaged in existing AMPS-TDMA cellular networks. To meet growth requirements, it is often required to adopt reuse schemes with smaller reuse distances, and this in turn results in modification of the existing frequency plan. The proposed frequency transition scheme allows for gradual expansion, smooth transition and also unobtrusive co-existence offering minimal disturbance to the existing network. The plan also allows fractional reduction in cluster size and has the flexibility to adapt to varying traffic growth requirements.