In this paper the problem of flow control in fast, connection oriented communication networks supporting traffic generated by multiple sources is considered. The network is modelled as a dynamic system with different delay times. A nonlinear strategy governing the behaviour of the sources is proposed. The strategy combines Smith principle and feed-forward compensation with the conventional rela...

The possibility of polarization-mode dispersion (PMD) compensation in fiber-optic communication systems with direct detection using a simple channel estimation technique and low-density parity-check (LDPC)-coded orthogonal frequency division multiplexing (OFDM) is demonstrated. It is shown that even for differential group delay (DGD) of 4/BW (BW is the OFDM signal bandwidth), the degradation du...

We demonstrate what we believe to be the first real-time impairment-cancellation system for group-velocity dispersion (GVD) and differential group delay (DGD) for a 640 Gb/s single-channel signal. Simultaneous compensation of two independent parameters is demonstrated by feedback control of separate GVD and DGD compensators using an impairment monitor based on an integrated all-optical radio-fr...

In this work, an on-line dead-time compensation method based on a time delay control for a pulse-modulation (PM) synchronous motor drive is presented. Disturbance voltages caused by the dead time are estimated on-line without any additional circuits nor off-line experimental measurements. The estimated disturbance voltages are fed back to the voltage reference as compensation. The proposed meth...

We experimentally demonstrate a novel technique to process broadband microwave signals, using all-optically tunable true time delay in optical fibers. The configuration to achieve true time delay basically consists of two main stages: photonic RF phase shifter and slow light, based on stimulated Brillouin scattering in fibers. Dispersion properties of fibers are controlled, separately at optica...

The slow light device based on photonic crystal coupled waveguide was fabricated, and a tunable delay of 72 ps was obtained for 2-ps-wide slow light pulses by local heating, which corresponds to a tunable fractional delay of 36. This value was further enhanced to 110 by compressing the output pulses through self-phase modulation and dispersion compensation in external fibers. We applied this de...

The control delay in distributed control systems may be compensated on-line or off-line depending on the required quality of the output, available computational power of the controller node, time stamping and clock synchronizing facilities etc. Irrespective of the compensation technique, there is an upper bound to the constant or variable control delay, which is decided by the plant, controller...

This paper reports two advances in a slow light device consisting of chirped photonic crystal slab coupled waveguide on SOI substrate. One is concerning the delay-bandwidth product, indicating the buffering capacity of the device. We experimentally evaluated a record high value of 57 (a 40 ps delay and a 1.4 THz bandwidth). We also observed ~1 ps wide optical pulse transmission in the cross-cor...

Abstract: This paper addresses the remote tracking control of a mobile robot subject to a bilateral time-delay. The delay affects the system since the controller and the robot are linked via a delay inducing communication channel, such as the Internet, and consequently, the performance and stability of the system are compromised. Based on the notion of anticipating synchronization, a state esti...

Recent interest in networked control systems (NCS) has instigated research in various areas of both communication networks and control. The analysis of NCS has often been performed either from the network, or the control point of view and not many papers exist were the analysis of both is done in the same context. Here a simple overall analysis is presented. In the paper the procedure of obtain...