This paper describes a new biasing scheme for sensing circuits, namely an automated bias control (ABC) circuit, for high-performance VLSI's. The ABC circuit can automatically gear the output level of sensing circuits to the input threshold voltage of the succeeding CMOS converters. The sensing performance can be accelerated with the ABC circuit either by reducing excessive signal level margin between the sensing circuits and the CMOS converters or by reducing extra stage of signal amplification. Since feedback control of the ABC circuit ensures a correct dc biasing even under large process deviation and circuit condition changes, wider operation margin can also be obtained. Three successful applications of the ABC circuit are reported: a sense amplifier, an address transition detector (ATD), and an ECL-CMOS input buffer. A 64-kb BiCMOS SRAM employing the proposed sense amplifier and the ATD has been fabricated with a 0.8-µm 9-GHz BiCMOS technology. The SRAM has an address access time of 4.5 ns.

Integration of 21/2D sketches obtained at different observing stations into a consistent world (or object) representation is one of the central issues in computer vision and robotics. The resolution and accuracy of 21/2D sketches may be different from one view point to another, and inconsistent data between different observations may occur. This paper presents one approach to building a 3-D world representation from range image sequences for road scenes including moving objects. First, a range image is transformed into a height map representing the height information from the ground plane on which the observer is assumed to lie, then it is segmented into the ground plane and objects on it. In order to capture the resolution and accuracy of the range data and to reprsent the consistency of the height information between different height maps, we define a reliability of the height information for each grid on the height map. Using the reliability, the system finds the correspondences of both static and moving objects between different observations, and successively refines the height information and its reliability with newly acquired data, dealing with inconsistent data. We show the results applied to road scenes which are physically simulated by landscape toy models using a range finder based on the structured light.

A narrowband interference in direct sequence spread spectrum communication systems also affects the characteristics of a delay lock loop. In this paper, the delay errors of a baseband delay lock loop (DLL) in the presence of the interference which consists of a narrowband Gaussian noise and several tones are examined, and when a filter is used to reject the interference, the characteristics of the DLL are analyzed using the Fourier method. Furthermore, from the calculation results of the delay error in case where a prediction error filter with two-sided taps is used as the rejection filter, it is shown that the filter is necessary to keep the DLL in the lock-on state.