The present invention concerns a diversity transmitter and a corresponding diversity transmission method. A symbol matrix is input for being processed, the processing comprising supplying columns of the symbol matrix to a plurality of at least two branches, each branch being supplied to a respective one of spatial channels for transmission. Parallelization is performed so as to provide within each branch at least two parallel channels allocated to a respective user. The symbol matrix signals is ...

A multiple-channel microwave communications system with an improved diversity switch permitting the system to be constructed without the necessity of equalizing channel delays wthin a 1/2 bit period by adjusting coaxial cable lengths. The average clock frequency is made to be the on-line channel frequency. The off-line clock frequency is forced to assume the on-line clock frequency by shifting the off-line clock one-half bit, that is 180.degree., when it is advanced or delayed more than 180.degr...

The present invention relates to a cooperating arrangement for a pair of space diversity stations (30 and 40) interconnected by a communication link (20) wherein each station normally communicates independently with a remote point (12) of the system while handling traffic related to a separate service region (32 and 42) or separate portion of an overall service region. At the occurrence of a fade condition at one of the two stations, the fading station alerts the other station of the pair of suc...

To reduce fading in a diversity receiver, the signals received on two spaced-apart antennas are added together without phase shift while amplitude of the sum is above a certain threshold. When the signal falls below the threshold, the signal from a squelch detector causes the sum amplitude to be stored and then a 180.degree. time delay to be inserted between one of the antennas and the adding circuit, after which time, the new sum amplitude is compared with the stored signal amplitude. If the ne...

A spatial diversity system for digital mobile telephone networks which comprises at least two antennas, one antenna being part of a primary (or master) unit and the other being part of a diversity (or slave) unit, each unit having processing means to detect the "quality" of digital audio signals received by their respective antennas, the "quality" comprising link quality, AGC level and parity errors; the primary unit being capable of comparing the "quality" of the audio signals received by each ...

A frequency diversity receiver system operating over a predetermined bandwidth comprising a first mixer receiving two identical information signals widely separated in frequency, a stepping oscillator with a predetermined number of steps controlling the output frequency of said mixer, two frequency channels at the output of said mixer, the first of said channels having a broad bandwidth filter and the second having a narrow bandwidth filter, a second mixer receiving simultaneously the output of ...

Methods for improving the availability of information derived from signals received from an object irradiated with coherent pulses of any form of radiation that exhibits a wave nature are disclosed. A method for reducing speckle derives separate component noncoherent signals from the received signals, and combines these separate noncoherent signals to form improved composite noncoherent signals. Weighting and processing of component signals can be applied as a function of time, frequency, and si...

A jittering idle channel is tracked to a jittering active channel and diversity switching to the idle channel is provided without loss of a bit. The signal received in the idle channel is written into an elastic store bit-by-bit as it is received; the signal is read out in the order in which it was written at times determined by a timing signal derived from the active signal and modified under control of an error signal indicating a timing difference between the signals on the active and idle ch...

In a space diversity receiver for receiving broadcast signals and having first and second antennas coupled to first and second receiving circuits, respectively, for supplying first and second output signals therefrom to a switching circuit which normally selectively supplies the one of the output signals detected to have a superior or better signal to noise ratio; a judging circuit is provided for comparing the better signal to noise ratio of an output signal with a predetermined value and for p...

A space-diversity receiving system for microwave band radio communication including two antennas and receivers, an endless phase shifter, a hybrid combiner, a hybrid distributor, a voltage controlled oscillator, a signal mixer, a low pass filter, a detector, and a control circuit. Microwaves received by the antennas are detected by the receivers. One received signal is directly applied to the hybrid combiner. The other received signal is applied to the hybrid combiner via the endless phase shift...