Abstract: The present invention provides a radar for a road vehicle. The radar comprises a beam-forming network having a first number of input ports and a second number of beam-forming ports, wherein the first and second numbers are greater than 1; a first number of antennas, wherein the first number of antennas is for receiving signals and each antenna in the first number of antennas is connected to a respective input port of the beam-forming network; a second number of receivers, wherein at least two receivers can operate simultaneously, each receiver is connected to a respective beam-forming port of the second number of beam-forming ports; a third number of antennas, wherein the number of antennas is for transmitting a signal, wherein the third number is greater than 1; and a processing means configured to determine the position of an object relative to the radar based on the magnitudes of the signals received by the receivers.

Abstract: An intruder detection system comprising a pair of detection nodes supporting a bidirectional wireless communication link across which each node is capable of sending a wireless signal to and receiving a wireless signal from the other paired node. Each node analyses the wireless signal received from the other node to detect one or more characteristics of the received signal that is indicative of a target in the detection zone. Each node is operable in a transmit mode in which it transmits to the other paired node, and a receive mode in which it receives from said other paired node, each node switching periodically between modes.