Abstract: A digital tester includes a digital data pattern aligner. The digital data pattern aligner includes an alignment pattern source, a data shifter, and a data comparator. The alignment pattern source sends an alignment pattern to the comparator in a data stream. The comparator samples the data stream and compares the samples to a copy of the alignment pattern. The shifter shifts the data in the data stream so long as the comparator detects no match between a data stream sample and the copy of the alignment pattern. When a match is detected, the pattern source and the comparator are in alignment and other data, such as test patterns, may be sent to the comparator or associated components.

Abstract: A data shifter selects data from a plurality of data blocks to effectively “window” data contained within the blocks. A second stage of shifting may be implemented by selection among the resultants of the windowing step. Such a shifter may find use in a data aligner.

Abstract: A communication system having gateway filter and switching networks in forward and return channels of a frequency reuse communication satellite. The system couples subscriber terminals to the Internet or other terrestrial network by way of one or more gateways. The system cross-straps gateway-to-user beam connectivity provided by the communication satellite to allow full coverage of all user beams with a subset of the gateways having reduced frequency reuse. An exemplary system comprises a communication satellite having a return channel and a forward channel. One or more gateways are coupled to the Internet or other terrestrial network and communicate with subscriber terminals by way of the return and forward channels provided by the satellite. The return and forward channels each comprise a filter and switching network that selectively couple signals between the one or more gateways and the subscriber terminals.

Abstract: A digital tester includes a digital data pattern aligner. The digital data pattern aligner includes an alignment pattern source, a data shifter, and a data comparator. The alignment pattern source sends an alignment pattern to the comparator in a data stream. The comparator samples the data stream and compares the samples to a copy of the alignment pattern. The shifter shifts the data in the data stream so long as the comparator detects no match between a data stream sample and the copy of the alignment pattern. When a match is detected, the pattern source and the comparator are in alignment and other data, such as test patterns, may be sent to the comparator or associated components.

Abstract: A data shifter selects data from a plurality of data blocks to effectively “window” data contained within the blocks. A second stage of shifting may be implemented by selection among the resultants of the windowing step. Such a shifter may find use in a data aligner.

Abstract: A communication system having gateway filter and switching networks in forward and return channels of a frequency reuse communication satellite. The system couples subscriber terminals to the Internet or other terrestrial network by way of one or more gateways. The system cross-straps gateway-to-user beam connectivity provided by the communication satellite to allow full coverage of all user beams with a subset of the gateways having reduced frequency reuse. An exemplary system comprises a communication satellite having a return channel and a forward channel. One or more gateways are coupled to the Internet or other terrestrial network and communicate with subscriber terminals by way of the return and forward channels provided by the satellite. The return and forward channels each comprise a filter and switching network that selectively couple signals between the one or more gateways and the subscriber terminals.

Abstract: A snow thrower is provided a pair of wheels on each side. The snow thrower includes two laterally spaced wheel drive assemblies for independently supplying power from the engine to each pair of wheels. Each wheel drive assembly includes a drive sprocket, which receives input from the engine, and front and rear driveable sprockets, which are operably associated with front and rear wheel axles to drive one pair of wheels. Each wheel assembly may be operated independently to provide power steering control.

Abstract: An extremely narrow-band bandpass electromagnetic filter comprises a waveguide (1) dimensioned below cutoff and having two or more active sections (30) each containing a dielectric resonator (6). The number of resonators (6) corresponds to the number of poles of filtering. The physical dimensions of the waveguide (1) can advantageously be further reduced by means of passive coupling means (40), where the waveguide (1) cross-section is smaller than in the active sections (30). Each passive coupling means (40) inductively couples adjacent active sections (30). Mode suppression rods (10) electrically connect opposing waveguide walls (2, 3) midway between each pair of adjacent dielectric resonators (6). Preferred embodiments are illustrated, in which the resonators (6) are tranversely oriented within the waveguide (1). Electromagnetic energy travels within the waveguide (1) in a single TE.sub.10 evanescent mode (TE.sub.01.delta. within the resonators (6)).