General Dynamics

About: General Dynamics is a company organization based out in Fairfax, Virginia, United States. It is known for research contribution in the topics: Signal & Propellant. The organization has 5722 authors who have published 5819 publications receiving 85768 citations. The organization is also known as: GD & General Dynamics Corporation.

Quasi parallel cyclic redundancy checker

Abstract: Method and apparatus for operating a CRC in a parallel, quasi parallel or serial fashion. The device allows all the bits in a word to be read and loaded into the cyclic redundancy checker (CRC) register in one clock cycle putting it in sync with the rest of the system. The CRC consists of a set of logic gates for converting a parallel input signal to a converted parallel input signal that is the equivalent of the conversion performed on the serial data input into the prior art cyclic redundancy checkers. The bits of the converted parallel input signal are then combined in another set of logic gates to provide the CRC output.

State metric memory arrangement for a viterbi decoder

Abstract: An improved memory utilization arrangement for a VITERBI decoder which allows the amount of memory required for storing state metrics to be minimized. Both old and new state metrics are required to be stored. This scheme utilizes memory locations for which old metrics have been previously read for storing the newly calculated metrics. In one implementation of this invention, a barrel shifter is used to calculate the address at which to store and retrieve the appropriate metrics. Another implementation employs a shift register with a shifting and inserting operation to align the metrics in the proper order and at the same time store the new metrics for subsequent calculations. As a result of the saving of memory, the amount of memory and power consumption are reduced substantially.

Spectral emissivity measurements of the 4.3 - micron co2 band between 2650 and 3000 k.

Abstract: Spectral-emissivity measurements of the 4.3-μ CO2 band were made at high temperatures. Under the conditions of the present experiments, the fine structure in the 4.3-μ CO2 spectrum is smeared out and comparable with a weak-line band model. A comparison of the observed spectral emissivities with theoretical band-model calculations shows good agreement. The measured integrated intensity of the 4.3-μ CO2 band between 2650° and 3000°K is 2850 (cm−1/cm at STP) and agrees well with measured room-temperature values.