It is also possible to modify this approach so that the modulated signal can be received by a standard receiver, but an improved receiver will be needed to realize the benefits of adaptive modulation. Current research will attempt to determi ne the degree to which channel degradations are removed when the signal is displayed on an improved receiver, and how much the signal is distorted when displayed on a standard receiver. Professor Lim also conducts research on motion estimation for motion compensation in image coding. Motion estimation can be used to improve image sequence restoration, and interpolating between two adjacent image frames. To achieve this, a design algorithm has been developed with improved convergence behavior over existing methods for the special cas e of a two-channel perfect reconstruction filter bank.
Additional research applies image processing techniques to speech spectrograms.
VLBI can give extremely precise position measurements, and researchers would like to use this technique to determine if nearby stars have planetary companions. Professor Hewitt examines how a star's radio emission varies with time, so it is necessary to exclude other sources of emission and interference from the data. Under the direction of Professor Jacqueline N. Hewitt, student James Brody has calculated theoretical images of the object and has developed an automatic technique to compare theoretical images with the data. One activity of RLE's Radio Astronomy group is the exploration of matter and energy in the universe associated with the gravitational lens effect. Working to study this phenomenon are Professors Bernard F. Burke and Jacqueline N. Hewitt .