摘要 |
An antenna diversity system comprises at least two antennas (202, 212). In a first embodiment each antenna is connected via a common connection point (222) to a receiver (224), by means of a respective switch (204, 214) which presents a low impedance connection between the antenna and receiver in the on state and a substantially reactive load (210, 220) to the antenna (202, 212) in the off state. Selection of appropriate impedances for the off state load enables the antennas (202, 212) to function as an array with a variety of beam patterns depending on the state of the switches (204, 214). Cycling through a sequence of switch states steers the antenna beam providing improved resistance to fading and multipath effects. In a second embodiment the antennas are connected to a hybrid coupler, which enables two beam patterns to be available simulaneously for signal quality measurement and comparison.
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