Title :
A fiber optic/millimeter-wave radio transmission link using HBT as direct photodetector and an optoelectronic upconverter
Author :
Suematsu, Eiji ; Imai, Nobuaki
Author_Institution :
ATR Opt. & Radio Commun. Res. Labs., Kyoto, Japan
fDate :
1/1/1996 12:00:00 AM
Abstract :
The performance of a fiber optic subcarrier link using an HBT as a direct photodetector and an optoelectronic up-converter in 50 GHz band has been experimentally investigated at a wavelength of 0.83 μm. From comparison with the performances of links using other MMIC-compatible photodetectors and with that of a high speed PIN-photodetector, this paper shows that the HBT-photodetector is superior to the other MMIC compatible photodetectors (MSM and HEMT). It is also shown that HBT not only has a high photodetection ability in the millimeter-wave band but also provides low conversion loss between a microwave subcarrier modulated by an optical signal and a millimeter-wave carrier. Also demonstrated are video FM-subcarrier transmission and 140 Mbps QPSK digital radio transmission using an HBT optical/RF transducer. At transducer transmission power of around -20 dBm, the HBT optical/RF transducer allows 50 GHz band radio transmission over optical fiber to achieve a weighted SNR of more than 50 dB and a data rate of 140 Mbps in indoor application
Keywords :
bipolar MMIC; digital radio; frequency modulation; heterojunction bipolar transistors; integrated optoelectronics; microwave links; optical fibre communication; optical receivers; photodetectors; quadrature phase shift keying; subcarrier multiplexing; visual communication; 0.83 micron; 140 Mbit/s; 50 GHz; HBT direct photodetector; HBT optical/RF transducer; MMIC-compatible photodetectors; QPSK digital radio transmission; fiber optic subcarrier link; fiber optic/MM-wave radio transmission link; indoor application; low conversion loss; microwave subcarrier; millimeter-wave band; millimeter-wave carrier; optoelectronic upconverter; video FM-subcarrier transmission; HEMTs; Heterojunction bipolar transistors; High speed optical techniques; MMICs; Optical fibers; Optical losses; Optical modulation; Photodetectors; Radio frequency; Transducers;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
