We report on our research activity on the problem of how to optimally partition the available bandwidth of frequency division duplex, multi-input single-output communication systems, into subbands for the uplink, the downlink, and the feedback. In the downlink, the transmitter applies coherent beamforming based on quantized channel information which is obtained by feedback from the receiver. As...

Some recent papers [5, 9] have shown that congestion control based on additive increase and multiplicative decrease tends to share bandwidth according to proportional fairness. Proportional fairness is a form of fairness which distributes bandwidth with a bias in favour of ows using a smaller number of hops; this is in contrast with max-min fairness, which gives absolute priority to small ows. ...

In a wireless environment, guaranteeing QoS constraints is challenging because applications at multiple devices share the same limited radio bandwidth in the network. In this paper we introduce and study a resource management model for centralized wireless networks, using feedback control theory. Before applying in practice, the proposed model is evaluated using the well-known 20-sim dynamic sy...

N egative feedback techniques are widely used in analog and RF design to improve circuit properties such as variation tolerance, bandwidth, impedance matching, and output waveform distortion. In practice, unwanted local return loops also exist around individual transistors through parasitic capacitance. As the size of transistors continues to shrink and the bandwidth of transistors continues to...

Being widely used in industrial systems and manufacturing lines, precision position control systems need to use high feedback control gains to reject disturbances. However, phase-lag in velocity estimation resulting from encoder measurement imposes a limitation on maximum allowable feedback gains, when system stability and control smoothness are concerned. In this paper, use of velocities deriv...

A novel DC bus voltage estimation algorithm with inherent cancellation of feedback voltage ripple is presented in this work. Design issues are discussed and simulation results are presented. Apart from reduction of output voltage sensor, the proposed estimation algorithm also eliminates twice the line frequency ripple from the feedback path allowing a voltage controller bandwidth comparable to ...

This paper presents a high CMRR and wideband current feedback Instrumentation Amplifier (IA). The proposed IA architecture consists of Fully Balanced Differential Difference Amplifier (FBDDA) and Differential Difference Amplifier (DDA) based on 2 generation current conveyor (CCII) with a buffer. From the simulation results evaluated by HSPICE, the proposed IA exhibits average CMRR was 109.3 dB ...

We propose and demonstrate a measurement technique of the intrinsic modulation responses semiconductor lasers with high sensitivity in wide frequency range. The is based on two-tone optical lock-in detection an spectrum having sidebands. measured response conventional 1.55-mm distributed feedback laser indicates that improves signal-to-noise ratio by 22 dB. This significant improvement allows u...

– The deÞning characteristic of a networked control system (NCS) is having a feedback loop that passes through a local area computer network. Our two-step design approach includes using standard control methodologies and choosing the network protocol and bandwidth in order to ensure important closed-loop properties are preserved when a computer network is inserted into the feedback loop. For su...

Power control is considered as an important means to combat near-far fading effects and maintain acceptable connections in wireless communications systems. When applying power control in practice, the performance is restricted by a number of fundamental limitations. Here, these are addressed from a control theory perspective. Limited update rate, limited feedback bandwidth, time delays, measure...