Abstract: A method of processing digital image data such as obtained from a television screen for transmission along telephone lines such that the transmitted data can be transformed to produce images in color. The method includes storing a frame of incoming digital image data in a frame buffer, transferring a group of tiles from the frame buffer to a tile buffer, generating a clock signal, generating address and sets of control signals in a state machine, applying the clock signal to a digital transformer and applying each address and set of control signals to the tile buffer to directly transfer a block of data in the tile buffer to the digital transformer. Next the data in the block is transformed, returned to the tile buffer and is written over the corresponding untransformed data in the tile buffer. These steps are repeated until all tiles in the tile block have been transformed and returned. The transformed tiles in the tile block are then coded so as to complete their compression.

Abstract: A rotary switch which includes a rotary actuator, a linear switch having a linear actuator and a rotary to linear translator interconnecting the rotary actuator to the linear actuator. Rotation of the rotary actuator causes the translator to move linearly and, in turn, to move the linear actuator.

Abstract: A phase modulator for a position indicating radio beacon which includes a digital memory circuit having a plurality of sets of stored numerical amplitude values with each set corresponding to a sine wave of a given phase and with at least three values in each set. A selection circuit selects phase values from the memory circuit in steps between a predetermined angular range in response to input data and, for each phase value, transfers the set of amplitude values in series at spaced apart time intervals to a digital to analog converter. A high frequency filter has an input coupled to an output of the digital to analog converter such that a sine wave is produced at an output of the high frequency filter.

Abstract: An attenuator circuit having a resistive "T" network and a resistive "Pi network in parallel with said "T" network.

Abstract: A microwave frequency doubler circuit, which includes a full wave rectifier for rectifying an input signal and to provide two outputs, and a differential amplifier having inputs connected to the two outputs.

Abstract: A method of transmitting broadband video services from a broadband digital signal source which includes forming the digital signal from said source into a plurality of channels of digital signals and modulating a plurality of carrier signals with respective channels of the digital signals. The resultant modulated channels are multiplexed to form a combined signal which is then used to modulate light from a laser light source. The modulated light signal is transmitted along a light fibre to a local distribution box where it is converted to electrical signals and broadcast to a number of subscriber set top terminals, Each set top terminal detects the modulated signal of a channel pre-assigned to that set top terminal. User control information is also received by that set top terminal and transmitted to the central office.

Abstract: A release mechanism for a buoyant object which includes a strap enclosing the object, an engaging mechanism for releasably engaging ends of said strap and an actuator for actuating the release of the ends of said strap in response to an increase in water pressure to a predetermined level.

Abstract: A digital modulator for modulating a stream of incoming data bits in which at least each one of the bits corresponds to a symbol. The modulator includes storage for each incoming set of symbol bits, where there is at least one bit in each set, of "n" successive symbols where "n" is a positive integer with a value greater than or equal to 1, with the oldest stored set being discarded upon the arrival and storage of a next set of symbol bits. Memory stores sample values corresponding to a modulated symbol impulse response for each of a predetermined number of symbols wherein the modulated symbol impulse responses each extend over "n" symbol periods. Sample values over one symbol period are retrieved from the memory for overlapping portions of each of the modulated symbol impulse responses stored in the storage. An adder sums the sample values which correspond to each other in time for each of the modulated symbol impulse responses corresponding to the received symbols.

Abstract: A dielectric test device formed on a substrate which includes a conductive ground plane layer formed over the substrate, a dielectric layer over the ground plane layer and a short and long conductive strip overlying the dielectric layer. Each of the long and short strips extends between common input and output conductive pads and are substantially identical in all respects except for length. Measurement of the interference pattern at the output node resulting from an input signal of a single frequency applied to the input node as frequency is varied over the gigahertz range allows the calculation of effective dielectric constant, propagation velocity as a function of frequency and attenuation.