Frequency-Doubled and Phase-Coded RF Signal Generation Based on Orthogonally Polarized Carrier-suppressed Double Sideband Modulation

Broadband Microwave Signal Processing Enabled by Polarization-Based Photonic Microwave Phase Shifters

“…For the above methods, the maximum operating frequency is limited by the bandwidth of the electro-optical modulators and the electrical devices used in the system. To break the bandwidth limitation, approaches that can perform simultaneously frequency multiplication and phase shifting are highly desirable [28], [29], [33]- [35]. The key is to generate two orthogonally-polarized wavelengths separated by a frequency that is multiple times of the frequency of the input RF signal.…”

Generation of a frequency-quadrupled phase-coded signal using optical carrier phase shifting and balanced detection

“…The main drawback of this method is that the two optical paths are physically separated and independently processed, which makes the signal suffer severely from environment variations. To improve stability, polarization modulation technique can be utilized, thanks to the complementarily phase-modulation function of the integrated polarization modulator (PolM) [8][9][10][11][12][13]. However, the schemes based on the polarization modulation are usually complicated and costly due to the use of multiple modulators.…”

“…To overcome the frequency restriction caused by the bandwidth of the modulator or electrical devices, frequencymultiplication technique is highly desired at the time of generating a high-frequency phase-coded signal. Previously, a frequency-doubled phase-coded signal was generated [7,11,12], but the frequency multiplication factor is small, which can hardly support high-frequency applications. The generation of a frequency-quadrupled phase-coded signal has also been proposed [8], but the polarization maintaining fiber Bragg grating (FBG) used in the scheme is wavelength and polarization dependent, making the frequency tuning range very limited.…”

Generation of a Frequency-Quadrupled Phase-Coded Signal With Large Tunability

“…To overcome this problem, polarization modulation based approaches were proposed [7][8][9][10][11][12], in which two orthogonally-polarized wavelengths are first generated and then complementarily phase modulated in a polarization modulator (PolM). One of the key steps in these approaches is the generation of the orthogonally-polarized wavelength pair, which can be realized by employing a differential group delay (DGD) element [7], a polarization-maintaining FBG (PM-FBG) [8], a PolM followed by an optical filter (OF) [9][10][11], or a dual-parallel polarization modulator [12]. However, all these approaches can only generate a phase-coded signal in a relatively small frequency range which is limited by the frequency dependence of the optical components or the bandwidth of the modulators and electrical devices.…”

“…To increase the frequency range of the photonic microwave phase-coded signal, frequency multiplication with high multiplication factor is highly desired. Previously, schemes for frequency-doubled phase-coded signal generation were reported [7,11,12], but the frequency multiplication factors are small, which can hardly support high frequency applications. Generation of a frequency-quadrupled phase-coded signal was also demonstrated [8], but its frequency tuning range is dependent on the polarization response of a PM-FBG.…”