Sharif Digital Repository

This paper presents a highly-linear transceiver core chip for X-band phased-array systems with two RX and one TX channels. Implemented in a standard 0.18-μm CMOS technology, the core chip provides 6-bit phase control (with rms error <2°) and 6-bit gain control (with rms error <0.6 dB) both within the 8.5–11.5 GHz frequency band. Improved accuracy is also available by digital calibration in narrowband applications. The receivers achieve a gain of 13.5 dB, an IIP3 of +10.3 dBm, and a noise figure of 8.2 dB, while drawing 170 mA per channel from the 3.3 V supply. The chip also provides an additional low-gain mode which further enhances IIP3 to +19.1 dBm and the input-referred P1dB to +11.4 dBm.... 

Using the ellipsoidal cavity model, the quasi-monoenergetic electron output beam in laser-plasma interaction is described. By the cavity regime the quality of electron beam is improved in comparison with those generated from other methods such as periodic plasma wave field, spheroidal cavity regime and plasma channel guided acceleration. Trajectory of electron motion is described as hyperbolic, parabolic or elliptic paths. We find that the self-generated electron bunch has a smaller energy width and more effective gain in energy spectrum. Initial condition for the ellipsoidal cavity is determined by laser-plasma parameters. The electron trajectory is influenced by its position, energy and...