Abstract: In a geo-location system, the location of an object in space is determined by transmitting polarized signals towards the object. To prevent erroneous determinations due to signals which reach the object after reflection the transmitted signals are polarized. The receiver at the object includes a cross-polarization discriminator and accepts only directly transmitted signals and not reflected signals which have been cross-polarized by the reflection. The transmitted signals may be ultra-wide band signals which can penetrate into buildings. An object whose location can thus be determined can also transmit polarized signals to another object which can not be reached by signals from the original transmitter. Further the ultra-wide band signals may utilize transmission in discontinuous frequency bands to avoid interference with existing systems.

Abstract: A method and apparatus diversity-combine radio signals received from a plurality of branches (108, 214). Each radio signal comprises a plurality of subchannels (806). The radio signal from each branch (108, 214) is digitized (904) into digital samples that are converted (908, 910) into frequency domain signals (702, 712). Each frequency domain signal (702, 712) corresponds to a subchannel and a branch (108, 214). A weighting factor is determined (916) for each branch (108, 214) and each subchannel (806) from instantaneous signal energy and noise power calculated (912, 914) from the frequency domain signals (702, 712). The frequency domain signal (702, 712) corresponding to each branch (108, 214) and each subchannel (806) is multiplied (918) by the weighting factor therefor to produce weighted frequency domain signals corredponding to each branch and each subchannel.

Abstract: A frequency shift keyed receiver (214, 220, 218) estimates a carrier frequency and demodulates (1020) a symbol value associated with the carrier frequency. During symbol intervals, the receiver (214, 220, 218) receives a radio signal including symbol values (502-518) corresponding to predetermined frequency offsets (604, 606) from a carrier frequency. The radio signal is digitized (1008) during a symbol interval, and then converted (1010) into a frequency domain signal. The frequency domain signal is stored (1012), and additional symbol intervals are converted to obtain a plurality of frequency domain signals, which are processed to generate (1016) a composite frequency domain signal (702, 704). A windowing function (706) of predetermined shape is convolved (1018) with the composite frequency domain signal (702, 704) to locate a frequency distribution therein that corresponds to the predetermined frequency offsets (604, 606).

Abstract: A manually shiftable transmission for use in automobiles with the usual driven shaft, axially aligned with a drive shaft. The usual gears, (for example, first, second, third, and fourth gear) are present on said shafts, to transmit a drive from any one gear to said driven shaft. Four sleeves, or driven members, are mounted by splines upon the main shaft and each is slidable thereon longitudinally of the shaft to pair with a gear. Each pair of driven member-and-gear has confronting lateral faces: on each said lateral face is formed one or more dogs to engage with the corresponding dog on a respective confronting face to transmit a drive from the gear to the driven member. The driven members are adapted for sliding travel by shifting forks between a neutral position and a drive position, in which the driven dogs on the driven member engage with the driving dogs on its companion gear.