ABSTRACT
Millimeter Waveforms............................................................ 221 7.3 Ultrabroadband Microwave Waveform Synthesis ............................. 227
7.3.1 Ultrawideband Systems, Applications, and Challenges ........................................................................ 227
7.3.2 Experimental Apparatus ......................................................... 229 7.3.3 Ultrabroadband Radio-Frequency and Microwave
Signal Synthesis ...................................................................... 233 7.3.4 Spectral Engineering of Ultrabroadband
Radio-Frequency and Microwave Waveforms....................... 236 7.3.5 Amplification of Ultrawideband Waveforms......................... 243
7.4 Application of Photonically Synthesized Waveforms to Compensate for Broadband Antennae Phase Distortions .................. 247
7.5 Conclusion .......................................................................................... 255 Acknowledgments ....................................................................................... 255 References.................................................................................................... 255
Femtosecond pulse shaping for generating nearly arbitrarily shaped ultrafast
optical pulses is now a well-established technology [1] and has been widely
adopted for applications ranging from high-speed communications to coher-
ent laser control of chemical reactions. Arbitrary waveform generation
(AWG) capabilities for millimeter-wave and microwave electromagnetic
signals, however, are quite limited. Commercial radio-frequency AWG in-
strumentation is currently limited to ~2 GHz bandwidth. Here, we review
work at Purdue in which shaped optical pulses are used to drive an optical-to-
electrical (O-E) converter. This leverages our femtosecond optical AWG
technology to achieve cycle-by-cycle synthesis of arbitrary voltage wave-
forms in the range of 1-50 GHz. Such capabilities could open new possibil-
ities for applications in areas such as wireless communications, electronic
countermeasures, sensing, and pulsed radar.
