Optoelectronic mixing, modulation, and injection locking in millimeter-wave self-oscillating InP/InGaAs heterojunction bipolar photo transistors - Single and dual transistor configurations
J. Lasri et al., Optoelectronic mixing, modulation, and injection locking in millimeter-wave self-oscillating InP/InGaAs heterojunction bipolar photo transistors - Single and dual transistor configurations, IEEE MICR T, 49(10), 2001, pp. 1934-1939
Citations number
16
Categorie Soggetti
Eletrical & Eletronics Engineeing
Journal title
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES
We describe an experimental investigation of two millimeter-wave oscillator
s one employing a single and the other using two InGaAs/InP heterojunction
bipolar photo-transistors (photo-HBTs). The single HBT oscillator can be op
tically injection locked to improve its spectral purity. Alternatively, it
can be modulated by analog or digital data carried by an optical signal. In
the two phototransistors case, one HBT oscillates and is optically injecti
on locked while the second serves as a modulator. The two-transistor case p
roved to be superior in terms of carrier spectral purity, analog modulation
efficiency and linearity as well as for digital modulation. Its advantages
stem from the better isolation between the local oscillator and modulating
signals and from the ability to separate the injection-locking and modulat
ion functions.