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Encoding algorithms generate a 32 x 64-bit matrix Reed-Muller code from a 6-bit orthogonal code-word. This increases error-free reception by a high rate telemetry channel under adverse signal noise with minimal use of additional hardware.
Design recommendations for integral brushless torquer-encoder based on Hall resolver principle
Low power encoder system using electron beam derived from cold source
Shaft misalignment effect on accuracy of precision digital shaft angle encoders, using test fixture and optical methods
Convolutional encoding and decoding developments, and applications in deep space communication
Encoders designed to generate comma free biorthogonal Reed-Muller type code comprising conversion of 64 6-bit words into 64 32-bit data for communication purposes
Problem of deterministic source encoding with fidelity criteron using computational work
N-P junction diode detector used in design of radioactive source non-contact encoder
Laboratory test set for integration of data compression and error correction encoding of digital communications system
Counting rate source encoding algorithm with orthogonal functions in space experiment data processing before telemetering to ground
Random images transmission rates, comparing line- by-line and two dimensional encoding
Hadamard transform source encoding application to Apollo unified S-band telemetry links, considering possible system performance improvement
Spatial frequency encoding is described as it applies to both photographic and television systems. In each case, color separations amplitude modulate spatial frequency carriers. The photographic system separates the carriers in the two-dimensional Fourier transform plane using coherent optics; the television system employs a two-dimensional electrical filter to perform the same separation. These filters are synthesized so that the two-dimensional bandwidths of the television camera are used efficiently. Nonlinear processing techniques are also described to minimize crosstalk between channels.
Abstracts are presented of research conducted on source encoding for two-dimensional data.
Electronic encoding altimeter has pulsed output with pulse width proportional to altitude and converts pressure-proportional input voltage to digital signal that may then be routed to monitoring or display equipment.
The disclosed encoder is adapted to produce both digital and analog output signals corresponding to the angular position of a rotary shaft, or the position of any other movable member. The digital signals comprise a series of binary signals constituting a multidigit code word which defines the angular position of the shaft with a degree of resolution which depends upon the number of digits in the code word. The basic binary signals are produced by photocells actuated by a series of binary tracks on a code disc or member. The analog signals are in the form of a series of ramp signals which are related in length to the least significant bit of the digital code word. The analog signals are derived from sine and cosine tracks on the code disc.
Contactless encoder is used at higher angular velocities and for objects lacking integral supporting shaft.
A precision capacitive shaft encoder providing a dc signal corresponding to the angular position of a shaft is described. Two variable capacitances are coupled in tandem by a rotatable shaft. Each capacitor has a capacitance that varies linearly with a change in the angular position of the shaft. The sum of the two capacitances is always constant for any angular position of the shaft. Each capacitance is alternately coupled to a reference dc voltage and a discharge circuit. The capacitances are electrically coupled in series and the charge periodically acquired at the junction of the capacitance is a function of the position of the shaft. An error-compensating voltage is imposed on the junction when the capacitances are coupled to the reference voltages. The junction is coupled to sample-and-hold apparatus provided with a error-correcting circuit.