Title :
High-speed QPSK modulator and demodulator with subharmonic pumping
Author :
Trambarulo, Ralph ; Schneider, Martin V. ; Gans, Michael J.
Author_Institution :
AT&T Bell Lab., Holmdel, NJ, USA
Abstract :
The authors describe a subharmonically pumped QPSK modulator and demodulator using pairs of beam-leaded Schottky diodes and appropriate high-pass and low-pass filters on dielectric substrates. A modulator and a demodulator were operated in cascade at a carrier frequency of 13 GHz with a common pump at 6.5 GHz. This circuit showed clean eye diagrams of the recovered data trains up to 1.5 Gb/s with corresponding error rates of less than 10/sup -11/. The circuits can be readily scaled to higher frequencies with a proportional increase of the information rate.<>
Keywords :
data communication equipment; demodulators; digital communication systems; microwave links; modulators; phase shift keying; solid-state microwave circuits; 1.5 Gbit/s; 13 GHz; 6.5 GHz; QPSK; beam-leaded Schottky diodes; broadband microwave circuitry; carrier frequency; cascade operation; common pump frequency; data trains; demodulator; dielectric substrates; digital transmission; high-pass filters; low-pass filters; modulator; phase shift keying; subharmonic pumping; Circuits; Demodulation; Dielectric substrates; Error analysis; Frequency; Information rates; Low pass filters; Optical modulation; Quadrature phase shift keying; Schottky diodes;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
