Millimeter-wave Signal Generation Research Articles

Millimetre-wave signal generationusing pulsed semiconductor lasers

A novel technique for millimetre-wave signal generation using a pulsed semiconductor laser is proposed and demonstrated. Optical filtering is used to select only two modes and suppress all other modes in the optical spectrum of the laser. The two selected modes beat together in a photodiode to generate a millimetre-wave signal with 100 % modulation depth.

Active and nonlinear wave propagation devices in ultrafast electronics and optoelectronics

We describe active and nonlinear wave propagation devices for generation and detection of (sub)millimeter wave and (sub)picosecond signals. Shock-wave nonlinear transmission lines (NLTL's) generate /spl sim/4-V step functions with less than 0.7-ps fall times. NLTL-gated sampling circuits for signal measurement have attained over 700-GHz bandwidth. Soliton propagation on NLTL's is used for picosecond impulse generation and broadband millimeter-wave frequency multiplication. Picosecond pulses can also be generated on traveling-wave structures loaded by resonant tunneling diodes. Applications include integration of photodetectors with sampling circuits for picosecond optical waveform measurements and instrumentation for millimeter-wave waveform and network (circuit) measurements both on-wafer and in free space. General properties of linear and nonlinear distributed devices and circuits are reviewed, including gain-bandwidth limits, dispersive and nondispersive propagation, shock-wave formation, and soliton propagation.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Acousto-optic liquid-crystal analog beam former for phased-array antennas

A compact phased-array antenna acousto-optic beam former with element-level analog phase (0-2π) and amplitude control using nematic-liquid-crystal display-type technology is experimentally demonstrated. Measurements indicate > 6-bit phase control and 52.6 dB of amplitude-attenuation control. High-quality error calibration and antenna sidelobe-level control is possible with this low-control-power analog beam former. Optical system options using rf Bragg cells or wideband Bragg cells are discussed, with the rf design being the current preferred approach. Transmit-receive beam forming based on frequency upconversion-downconversion by electronic mixing is introduced for the rf Bragg-cell beam former, and comparisons with digital beam forming are highlighted. A millimeter-wave signal generation and control optical architecture is described.

Efficient millimetre-wave signal generation through FM-IM conversion in dispersive optical fibre links

A frequency- or phase-modulated optical signal becomes intensity-modulated through dispersion in single-mode optical fibres. New theoretical results describing this effect are presented, and supported by observation of 12% intensity modulation at the 60 GHz harmonic of a 4 GHz signal applied to a three-contact DFB laser.

Synthetic millimeter-wave signal generation for length measurement

Synthetic millimeter-wave signal generation for length measurement

Generation of Millimeter-Wave Signals of High Spectral Purity

The generation of millimeter-(mm-) wave signals phase coherent to a lower frequency reference or standard implies a large multiplication factor with inherent amplification of the short term instability or phase noise. This effect which usually is of secondary importance at lower microwave frequencies may become a limiting factor in the implementation of some mm-wave digital communication systems. Techniques used for the generation of signals of high spectral purity are discussed, and illustrated with the realization for a low data rate mm-wave satellite communications system. Quantitative results are presented and analyzed in terms of the theoretical time and frequency domain relationships.