On– Off Error Control Coding Scheme for Minimizing Tracking Error in Wireless Feedback Control Systems

In wireless feedback control systems, reducing packet loss is critical. The use of channel coding may decrease such packet loss; however, redundancy in channel coding also decreases the packet transmission rate although the bit rate remains the same. Thus, control systems are highly affected by disturbances. To improve control system quality, channel coding should be adaptively employed on the basis of packet loss and disturbances. Herein, an on-off error control coding scheme based on the communication and control layers is proposed. In this scheme, channel coding is adaptively used to minimize tracking errors in a controlled plant. Results demonstrate that the proposed on-off error control coding scheme improves the control system's reference tracking performance compared with that when using a fixed-rate coding scheme.