The multi-antenna receiver has many use cases in wireless communications and Radar but it faces some major drawbacks such as high cost of hardware and high power consumption. Recent developments on narrow band systems have led to an alternative solution called Code-Division Multiplexing (CDM), using a single RF receiver front-end to receive signals from multi-antenna. For this purpose signals from the antennas are mixed with high speed spreading codes and then are combined at the RF stage. However, the use of high speed codes increases the signal bandwidth. Applying this solution on Ultra-Wide Band (UWB) systems is questionable because of the bandwidth increase. This paper discusses the principles and implementation of CDM technique on an Impulse Radio (IR) UWB system showing interesting insights. An experiment is performed to estimate the Angle-Of-Arrival (AOA) on the recovered signals in a basic indoor positioning scenario.