We describe a simple method for high-precision rotary angle encoder calibration for longrange angular errors. By using a redesigned electronic nulling autocollimator, an opticalpolygon artifact is calibrated simultaneously with determining the encoder error function over a rotation of 2π rad. The technique is applied to the NIST vacuum double crystal spectrometer, which depends on precise measu...

Hardware implementation of the JPEG 2000 image compression standard for real-time image compression requires implementation of the adaptive arithmetic encoder among other related algorithms. In this work, a system level design for the adaptive arithmetic encoder used in the JPEG 2000 standard is proposed. This design is based on the assumption that the bit-sequence and its corresponding context...

The β-encoder, introduced as an alternative to binary encoding in A/D conversion, creates a quantization scheme robust with respect to quantizer imperfections by the use of a β-expansion, where 1 < β < 2. In this paper we introduce a more general encoder called the βα-encoder, that can offer more flexibility in design and robustness without any significant drawback on the exponential rate of co...

Due to the magnetic nonlinearities, SRM drive control is complicated and normally requires a microprocessor or a DSP. This paper presents a simple and reliable SRM drive using an innovative encoder based on optical graphical programming technology. There is no microprocessor in the drive, no A/D or D/A circuitry, with a drive system that matches the simplicity of the motor construction. It feat...

In principle, to nd the optimal code one needs to optimize the tness functionH with respect to all its 2 m s degrees of freedom, the m s entries of the encoder e i and the m s entries of the decoder dj!, taking into account the m conservation relations for the encoder P i e i = 1 and the s conservation relations for the decoder P ! dj! = 1. However, although the degrees of freedom of the encode...

A generic M-ary continuous phase modulation (CPM) scheme, with a modulation index of h = 1/M, can be decomposed into a continuous-phase encoder (CPE) followed by a memoryless modulator (MM), where the CPE is linear over the ring of integers modulo M. By using a channel encoder (CE), which is a convolutional encoder, to operate over the same ring of integers modulo M, the CE and the CPE can be c...

Electrical drives frequently use incremental encoders as position sensor. The paper deals with the modeling and simulation of an incremental encoder and associated units for processing the information provided by the encoder. A mathematical model of the incremental encoder is presented. Based on encoder signals the direction of the rotation, the position and the speed are identified. The descri...

In this paper we introduce a VLSI priority encoder that uses a novel priority lookahead scheme to reduce the delay for the worse case operation of the circuit, while maintaining a very low transistor count. The encoder's topmost input request has the highest priority; this priority descends linearly. Two design approaches for the priority encoder are presented, one without a priority lookahead ...

Images typically contain smooth regions, which are easily compressed by linear transforms, and high activity regions (edges, textures), which are harder to compress. To compress the first kind, we use a “zero” encoder that has infinite context, very low capacity, and which adapts very quickly to the content. For the second, we use an “interpolation” encoder, based on neural networks, which has ...