ANTENNA ARRAY

摘要

P/8156/MRC (figure 2) Antenna Array A log periodic antenna array, each consisting of e.g. five dipoles D1 - D5 are each driven by a transmitter Tx by an amplifier A and phase shifter 5. Each antenna radiates generally from one dipole only for example dipole D4. The Applicants have discovered that the antenna may behave as if the radiation appears to emanate from the position marked with a cross. Probe antennas P1 - P3 are used to derive error signals representing the difference between the expected relative phase between a dipole and a probe antenna and the measured relative phase between the dipole and the probe antenna, which error signals are then used to apply corrections to the phase shifters PS.