Abstract: With a redundant GPS antenna splitter two GPS antennas are connected through an amplifier to a passive antenna splitter in parallel feeding mode, whereby the direct current supply of the antennas is provided by a DC driver stage, whose inputs (DC1 to DC8) are coupled with outputs of the antenna splitter of the connected transmitters in order to control the power supply with current measuring stages depending on the operating condition of the GPS antennas and to deliver a supply voltage both to the GPS antenna and HF-amplifier, if the antenna is active.

Abstract: A base station signal processing mechanism for a time division multiple access (TDMA) cellular communication system adaptively controls weighting coefficients of the base station's phased array antenna in a manner that forms a directivity pattern whose gain and/or nulls maximize the signal to noise ratio in the presence of co-channel users whose communication time slots overlap a communication time slot of a desired user. The signal processing mechanism performs correlation processing of synchronization patterns contained in signals transmitted by co-channel users to identify times of transitions between successive co-channel users' communication time slots relative to a time of transition of the desired user's communication time slot, and deriving weighting coefficients in accordance with the times of transitions.

Abstract: A coupler for transferring signals from a first group of single optical fibers to a second group of single optical fibers. The coupler provided for this purpose is a directional star coupler which is constructed so as to eliminate any need for the employment of a mixing chamber. A covering, or cladding, generally covers each optical fiber in order to prevent light from being emitted through the circumferential surface of such fiber. At an end portion of each of the fibers of both the first and second groups, the cladding is treated so as to allow light to be emitted from the circumferential surface of such portion. The end portions of the fibers of the first group are fed through an opening at one side of a coupling chamber. The end portions of the fibers of the second group are fed through another opening within the coupling chamber. The first and second groups of fibers are arranged within the chamber so that their end faces are in abutment with each other.