Implementation and performance of the RAKE receiver for CDMA

In the radio environment, transmitted signals arrive at the receiver via a direct, unobstructed path, or via multiple paths from the reflection, diffraction and scattering of surrounding objects such as buildings and trees. The signal at the receiver is significantly distorted and faded by the multipath propagation, witch lead to inter-symbol interference (ISI). Spread spectrum mobile communication systems use RAKE Receivers to minimize these communication errors resulting from multipath effects. Ideally, the number of correlators in the RAKE receiver should match the number of multipath signals. This paper presents an implementation of the RAKE Receiver and examines its Bit Error Rate (BER) performance varying the number of users, spreading factor, RAKE fingers within systems based on CDMA (Code Division Multiple Access) in a Rayleigh channel transmission.