Abstract
This paper is on a spread spectrum transmission system for multiplexing a number of sensory signals in a robot to reduce the number of wires of the signls. In the proposed system, each transmitter and a receiver are connected in series and the multiplexed signal is synchronized in each circuit with the system clock by newly developed analog signal phase shift circuits. The time required to demodulate a transmitted signal by utilizing the developed transmission system in which 127-bit M-sequence code is used is reduced to be 3ms for the adoption of the unique synchronization tracking method. Furthermore, the S/I ratio of the system is evaluated to be 23. 5 dB. The developed system has characteristics of the short accessing time and an advantage that any number of new sensors, with transmitters, can be inserted in a desired position among the existing sensors. Therefore, the developed system can be applied to devices in which many sensory signals are to be accessed in real time. In the paper, we discuss the way how to track the synchronization circuit by circuit and we describe the structure of the system and the circuits used. Finally, the developed system is evaluated in terms of the S/I ratio.
