Very highly efficient surface acoustic wave convolver using GaSb/InSb/AlGaAsSb heterostructures grown on LiNbO/sub 3/ substrates

Highly efficient surface acoustic wave (SAW) convolvers are required for application in spread spectrum communication systems. We present here for the first time the growth of GaSb/InSb/AlGaAsSb heterostructures on LiNbO₃ substrates by molecular beam epitaxy (MBE) and their application to a novel strip-coupled SAW convolver. As a result of investigating the semiconductor thin film structure and the output electrode structure, we have succeeded in obtaining very high efficiencies of more than -14 dBm (F-value). We have also studied the correlation properties of the strip-coupled SAW convolver using a square wave signal and a pseudonoise (PN) code signal.