Abstract Two incremental algorithms for drawing circles using short line segments are proposed in this paper. The proposed algorithms can draw manypoints at one time. They use only addition, subtraction, and shift operations except in the initialization of the algorithm. Using this simplified approach we can greatly increase the speed of drawing circles, relative to other conventional algorithms.

The "Bryn Processor" is a well-known array processor; its design depends on spectral densities of the signal and noise processes. Array output signal-to-noise ratio can be decreased because of errors in sampling times: (1) When array design parameters are estimated from sampled data; (2) when operating on sampled input data. We model errors in sampling times as a discrete-parameter random process. Expressions for array output SNR of the Bryn processor are determined for the two situations listed above. Numerical results are presented for some specific assumptions on signal, noise, and sampling error.

An adaptive sequential bit synchronizer for a random squarewave data process is proposed in this paper. The probability distributions of the signal parameters and noise process are assumed unknown. The synchronization algorithms, implemented on a small computer, are capable of accurately estimating pulse transition time, pulse amplitude, and pulsewidth simultaneously by invoking the Gauss-Markov theorem. Numerous simulations indicate that the performance of the synchronizer is satisfactory from the points of view of the amount of data required and the speed of convergence.