In this paper we investigate the peak-to-average power ratio (PAR) and its effects on the performance of Zipper-VDSL systems. The spectrum and the out of band power when passing through a nonlinear device is also investigated. We further evaluate the performance with a recently proposed PAR reduction technique for orthogonal frequency division multiplexing (OFDM). PAR reduction of Zipper-VDSL m...

|This paper describes a technique to handle temporal signal correlations during estimation of average power in sequential circuits. A key feature of the approach is that it provides an eecient and accurate way to estimate average power using a Monte Carlo based method. Results on a large number of benchmark sequential circuits connrm that the technique runs eeciently (up to two orders of magnit...

The measurement of the average received power is essential for power control and dynamic channel allocation in wireless communication systems. However, due to the effects of multipath fading and additive noise inherent to the wireless channel, there can be significant errors in such measurements. In this paper, the error statistics for average power measurements are considered; in particular, t...

The study of critical phenomena and universal power laws has been one of the central advances in statistical mechanics during the second half of the past century, explaining traditional thermodynamic critical points1, avalanche behaviour near depinning transitions2,3 and a wide variety of other phenomena4. Scaling, universality and the renormalization group claim to predict all behaviour at lon...

High peak to average power ratio of the transmit signal is a major drawback of OFDM systems. After defining the PAPR and analyzing its statistical properties, some of the most representative PAPRreduction techniques available in the literature are reviewed in detail. Several methods have been proposed to reduce the peak power of OFDM signals. In this paper the effectiveness of some recently pro...

Acknowledgement This master thesis is defined by ArrayComm company in U.S, California, San Jose. The project is a collaboration between the company and Chalmers. I would like to show my gratitude to certain people: Dr. Thomas Svantesson from ArrayComm-for giving me this opportunity and also your great guidance and help during the project. Professor Mats Viberg-for introducing me to the right pe...

We present our research on the high energy picosecond laser operating at a repetition rate of 1 kHz and the high average power picosecond laser running at 100 kHz based on bulk Nd-doped crystals. With diode-pumped solid state (DPSS) hybrid amplifiers consisting of a picosecond oscillator, a regenerative amplifier, end-pumped single-pass amplifiers, and a side-pumped amplifier, an output energy ...

We present a semiconductor saturable absorber mirror mode-locked thin disk laser based on Yb:Lu(2)O(3) with an average power of 141 W and an optical-to-optical efficiency of more than 40%. The ideal soliton pulses have an FWHM duration of 738 fs, an energy of 2.4 microJ, and a corresponding peak power of 2.8 MW. The repetition rate was 60 MHz and the beam was close to the diffraction limit with...

A moving-slab-geometry Nd:glass laser has been designed and demonstrated. An average power output of 43.8 W has been achieved at 2.76-kW input power and at 2.06% slope efficiency. The moving-slab laser has the potential for scaling to kilowatt average power levels.

In this paper, OFDM based on Software-Defined Radio (GNU Radio) to reducing the peak to average power ratio is developed and tested. Orthogonal frequency-division multiplexing (OFDM) is a method of encoding digital data on multiple carrier frequencies. OFDM has developed into a popular scheme for wideband digital communication, whether wireless or over copper wires, used in applications such as...