The default pulse shaping filter in the conventional multiple-input and multiple-output (MIMO) based orthogonal frequency division multiplexing (OFDM) system is a rectangular function, which unfortunately is highly sensitive to frequency synchronization errors and the Doppler spread. Shaped OFDM is able to considerably alleviate the effect of inter-carrier interference (ICI) as well as reduce t...

This dissertation focuses on the implementation of integrating pulse transmitter with wide-band antenna array into a chip by CMOS process for beam-forming in millimeter-wave (mm-wave) active imaging applications. Integrated antenna arrays in this research electrically control and steer radiated-pulse beams towards objects to be imaged. Among imaging approaches, active imaging method provides mo...

We have developed a low noise, low power charge sensitive ampli er and pulse shaping circuit. Our application is for a double-sided germanium strip detector, nominally providing 50 independent spectroscopy channels. An array of these detectors would provide signi cant improvements in imaging, spectroscopy, and sensitivity for space-based gamma-ray astronomy. The key features of these electronic...

In the design of optical communication systems for multigigabit transmission rates, a special care must be given to the post-detection receiver filter. A well-designed post-detection filter, effecting appropriate pulse shaping/noise reduction, can reduce significantly the degradation caused by the system impairments. The received solitons occupy just a fraction of the bit period, a feature that...

The reverse link bandwidth efficiency of a spectrally overlapped CDMA system with fast transmit power control is evaluated to find the optimum overlapping, where the bandwidth efficiency is defined as the maximum aggregate bit rate of all subsystems per unit bandwidth (bps/Hz). Single and multiple cell environments are considered. Besides the rectangular chip pulse, the impact of a pulse-shapin...

This paper presents a 1MHz bandwidth, ΔΣ fractional-N PLL as the frequency synthesizer for LTE. A noise cancellation path composed of a novel hybrid ΔΣ DAC with 9 output bits is incorporated into the PLL in order to cancel the out-of-band phase noise caused by the quantization error. Further, a re-timing circuit is proposed to reduce the nonlinearity in the Charge Pump and provide pulse shaping...

LLE Review, Volume 73 1 Pulsed-laser systems emit optical pulses having a temporal pulse shape characteristic of the particular type of laser design. Advances in technology have produced laser-pulseshaping systems where the laser temporal profile can be specified in advance and controlled to a high degree of accuracy.1–3 A pulse-shaping system has been in operation on OMEGA for several years. T...