Sri Andari Husen

Lighting systems control for demand response

Lighting is a major part of energy consumption in buildings. Lighting systems will thus be one of the important component systems of a smart grid for dynamic load management services like demand response. We consider the problem of control of multiple lighting systems in a building for providing demand response service. In the scenario considered in this paper, under a demand response request, lighting systems in a building react by executing dimming control to reduce power consumption based on their load shedding flexibilities. Load shedding flexibility reflects the amount of power reduction that can be achieved by an individual controller without violating minimum illumination requirements of occupants in that area. We consider different methods for distributing load reduction across the multiple lighting system controllers employing their respective load shedding flexibilities. The performance of the methods is compared with a scheme where uniform dimming is applied across the lighting systems.

Blind Estimation of Maximum Delay Spread in OFDM Systems

We present a new method of estimating the maximum delay spread of a channel in an OFDM system. The method differs from other approaches because it uses all active OFDM subcarriers (pilot and data) and therefore avoids the aliasing problem arising from the exclusive usage of pilot subcarriers. The method considers the transmitted data as a random probe signal for obtaining characteristics of a channel. Although the data content is not known at the receiver, it turns out that useful second order statistics can be extracted, from which the maximum delay spread is estimated. The method is shown to be robust to noise and Doppler spread.

Automatic switch between static and mobile operation modes in DVB-T/H receivers

In wireless communications, the receivers have to work properly both in the mobile and static environments. A proper solution might require the development of two parallel receivers modes. In this paper we propose an automatic switch between these two receiver modes. The automatic switch estimates a decision variable based on the temporal correlation of the channel frequency response. Then, it compares the decision variable with a pre-calculated threshold to decide which is the best receiver mode