An integrated electrically pumped opto-electronic mixer consisting of two I
nP/GaInAs heterojunction bipolar transistors in a cascode configuration is
demonstrated, Intrinsic downconversion gains of 18.2 and 8.9 dB at RP optic
al modulation frequencies of 3 and 9.5 GHz were obtained, The performance o
f the cascode mixer and a single heterojunction bipolar transistor (IJ;ET)
opto-electronic mixer are compared. The performance of the cascode mixer wa
s superior to the single HET mixer, mainly at high frequencies, Up and down
mixing conversion gains were measured and found comparable, A simulation w
as carried out by solving the nonlinear differential equations that corresp
ond to the large-signal equivalent circuit. The results of the simulation e
nabled us to identify the principal nonlinear components in the equivalent
circuit.