Frequency-Hopping Microwave Generation With a Large Time-Bandwidth Product

We propose and demonstrate an approach to generating large time-bandwidth product (TBWP) frequency-hopping (FH) microwave waveforms by using an ultra-high-quality factor (Q) silicon microring resonator (MRR) with thermal tuning. An ultra-high-Q MRR (Q ~ 10
⁶
) is used to filter out an expected frequency component from an optical frequency comb. Heterodyne beating between the filtered frequency and another seed frequency light detected by a photodetector will generate an FH microwave waveform. In addition, the FH microwave signal can be flexibly and independently tuned in terms of the central frequency, bandwidth, frequency order, and time sequence length, just altering the driving voltage on the MRR. The proof-of-concept experiments show that the TBWP of the stepped linear, stepped arbitrary, and Costas sequence microwave signal can be over 4.5 × 10
⁷
. Our paper offers an integrated FH microwave generation approach to support the optics communications and the next-generation photonic radar systems.