Multifunction GaAs MMIC transmitter/receiver for onboard satellite equipment
This paper describes the development of a new GaAs MMIC to be used in transmit/receive modules for S band transponders. The IC, which includes five different functions, reduces the sue of the system whilst maintaining and even improving system performance. Amplification, phase shifting, and mixing are some of the functions integrated in the same chip. The goal of the work is to reduce the number, size, and consequently, the cost of the circuitry currently in use through an European commercial Enhancement/Depletion (E/D) pHEMT process, compatible with low noise reception. A maximum conversion gain more than 54 dB has been achieved with a gain control more than 27 dB. A 0 dBm output power at 1dB compression point (P1dB) has been measured when a CW stimulus was used as input signal, while more than 35 dB of Adjacent Channel Power Ratio (ACPR) was tested for a BPSK input signal.
High-Frequency Analog Integrated Circuit Design
Integrated Circuit Processing Technology MESFET Design and Modelling Schottky Diode and Passive Components Basic Building Blocks Wideband Amplifiers Operational Amplifiers Mixers and Oscillators Data Conversion Circuits Synthesis of Linearized Conductance Functions.
Magnetic plasma confinement for laser ion source.
A laser ion source (LIS) can easily provide a high current beam. However, it has been difficult to obtain a longer beam pulse while keeping a high current. On occasion, longer beam pulses are required by certain applications. For example, more than 10 micros of beam pulse is required for injecting highly charged beams to a large sized synchrotron. To extend beam pulse width, a solenoid field was applied at the drift space of the LIS at Brookhaven National Laboratory. The solenoid field suppressed the diverging angle of the expanding plasma and the beam pulse was widened. Also, it was observed that the plasma state was conserved after passing through a few hundred gauss of the 480 mm length solenoid field.