Abstract:
A semiconductor integrated circuit for processing a plurality of received broadcast signals, such as GPS signals, is operable in two modes; acquisition and tracking. In an acquisition mode, a separate acquisition engine is used which includes a sample reducer for combining samples of a received signal for correlation with a locally generated version of a GPS code. A serial to parallel converter converts the reduced samples to parallel words which are correlated in parallel with locally generated words of the GPS code.
Abstract:
A semiconductor integrated circuit for processing a plurality of received broadcast signals, such as GPS signals, is operable in two modes; acquisition and tracking. In an acquisition mode, sample reducer combines samples of a received signal for correlation with a locally generated version of a GPS code. In a tracking mode, the sampled signal is provided direct to the correlators without sample reduction. The same correlators are thereby used to increase acquisition speed.
Abstract:
A computer system comprising a plurality of data processing elements connected through a shared communication bus to a memory so that for a given computer cycle at least one of the elements assumes control of the bus for accessing address in memory. The computer system having memory access circuitry connected between the data processing elements and memory which has first and second buffer units for storing prefetched bursts of data from the memory. The buffer circuit also having control logic for prefetching data in sequential bursts from the memory and storing the prefetched burst in the first or second buffer units and the control logic monitors the buffer units and the address to be accessed in memory to determine in which buffer the next fetched burst should be stored.
Abstract:
An associative memory comprises an array of memory cells arranged in rows and columns, each row comprising a plurality of segments each of which comprises a set of said memory cells, wherein each memory cell has compare circuitry for comparing input data with data stored therein and for generating a cell match signal when said input data matches said stored data and match signal combining circuitry for receiving a match signal from a preceding cell in the set and operable to generate a logical value dependent on the match signal of the current cell and the match signal of the preceding cell whereby each segment generates a resultant segment logical value, the memory further comprising combinatorial logic circuitry associated with each row for combining said resultant segment logical values to generate a final output match signal for that row.
Abstract:
The present invention provides a system, method and computer program product for efficient low power motion estimation of a digital video image wherein processing requirements are reduced, the reduction being dependent on the content being processed. The method performs motion estimation of a current video image using a search window of previous video image. The method comprises as a first step the formation of the mean pyramids of the reference macroblock and the search area. This is followed by full search at the lowest resolution. The number of CMVs propagated to lower levels is dependent on the QADE of the current macroblock and the maximum distortion band obtained during training for that QADE value at that particular level. The process of training over a sequence is triggered at the beginning of every sequence. This training technique is required to determine the value of the maximum distortion band for all QADEs of the macroblocks, occurring over the training frames.
Abstract:
An executable program is prepared from a plurality of object code modules, each object code module including section data and associated relocations and at least one of the object code modules further including code sequences at least some of which are like to be repeatedly included in the executable program. Wherever a code sequence is to be inserted a relocation instruction specifies the location of the code sequence and the code sequence is inserted into the section data at the appropriate point. A linker is provided for preparing a executable program from such a plurality of object code modules, the linker including a relocation module for reading relocations and being operable to identify a relocation specifying one of the above-mentioned code sequences, a section data module for holding section data into which a code sequence is to be inserted, and a program preparing means which prepares the executable program including the section data with the inserted code sequences. Also discussed is a method for assembling such an object code module and a computer program in the form of such an object code module, the computer program being co-operable with the linker to prepare said executable program.
Abstract:
A method for testing a semiconductor memory cell comprising first and second transistors in cross-coupled arrangement to form a bistable latch, the drains of the transistors respectively representing first and second nodes each for storing a high or low potential state, and each node being connected to a respective semiconductor arrangement for replacing charge leaked from the node and to a respective switching means, activatable by a word-line, for coupling the node to a respective bit-line, the method comprising the steps of: connecting the bit-lines to the low potential; activating the word-line to connect the first node to the first bit-line to allow any potential on the first node to fall towards the potential on the first bit-line; and monitoring charge flow from the first node to the first bit-line to test the operation of the first semiconductor arrangement.
Abstract:
A current reference circuit consists of two interconnected current mirrors, of which the two transistors of one current mirror have mutually different threshold voltages.
Abstract:
An integrated current reference comprises two current mirrors, the gate source voltage of one of the current mirrors being offset by a voltage reference element, which in an embodiment consists of an on MOSFET.