• Title, Summary, Keyword: Photonic microwave filter

Search Result 25, Processing Time 0.039 seconds

A Flexible and Tunable Microwave Photonic Filter Based on Adjustable Optical Frequency Comb Source

  • Tran, Thanh Tuan;Seo, Dongsun
    • Journal of IKEEE
    • /
    • v.19 no.1
    • /
    • pp.27-32
    • /
    • 2015
  • A flexible and tunable microwave photonic filter based on adjustable optical frequency comb source is demonstrated. We use a combination of a dual parallel Mach Zehnder modulator and an intensity modulator to generate fifteen comb lines with proper weights to implement a desired filter. The optical comb weights, corresponding to the tap coefficients of the filter, are flexibly changed by adjusting the operation parameters of the modulators. The achieved bandwidth and stopband attenuation of the tunable filter are 0.7 GHz and 20 dB, respectively. In addition, we overcome the undesired low frequency suppression appeared in a conventional scheme by applying a dual parallel Mach Zehnder modulator for single sideband suppressed carrier modulation.

Tunable Photonic Microwave Band-pass Filter with High-resolution Using XGM Effect of an RSOA

  • Kwon, Won-Bae;Lee, Chung Ghiu;Seo, Dongjun;Park, Chang-Soo
    • Current Optics and Photonics
    • /
    • v.2 no.6
    • /
    • pp.563-567
    • /
    • 2018
  • We propose and experimentally demonstrate a simple tunable photonic microwave band-pass filter with high resolution using a reflective semiconductor optical amplifier (RSOA) and an optical time-delay line. The RSOA is used as a gain medium for generating cross-gain modulation (XGM) effect as well as an optical source. The optical source provides narrow spectral width by self-injection locking the RSOA in conjunction with a partial reflection filter with specific center wavelength. Then, when the RSOA is operated in the saturation region and the modulated recursive signal is injected into the RSOA, the recursive signal is inversely copied to the injection locked optical source due to the XGM effect. Also, the tunability of the passband of the proposed microwave filter is shown by controlling an optical time-delay line in a recursive loop.

Microwave Photonic Filter Using Optical True-Time-Delay Line Matrix (광 실시간 지연선로 행렬을 이용하는 마이크로웨이브 포토닉 필터)

  • Jung, Byung-Min
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.26 no.2
    • /
    • pp.213-217
    • /
    • 2015
  • Microwave Photonic(MWP) filters capable of use a bandpass filter or a notch filter with large bandwidth have been proposed. 4-lines${\times}$2-bit fiber-optic delay lines with a unit time-delay difference of 50 ps were experimentally realized. By changing the time-delay difference and the coefficients of microwave-modulated optical signals, the bandpass and notch filters were implemented and characterized.

X-band Microwave Photonic Filter Using Switch-based Fiber-Optic Delay Lines

  • Jung, Byung-Min
    • Current Optics and Photonics
    • /
    • v.2 no.1
    • /
    • pp.34-38
    • /
    • 2018
  • An X-band microwave photonic (MWP) filter using switch-based fiber-optic delay lines has been proposed and experimentally demonstrated. It is composed of two electro-optic modulators (EOMs) and $2{\times}2$ optical MEMS-switch-based fiber-optic delay lines. By changing time-delay difference and coefficients of each wavelength signal by using fiber-optic delay lines and an electro-optic modulator, respectively, a bandpass filter or a notch filter can be implemented. For an X-band MWP filter with four channel elements, fiber-optic delay lines with the unit time-delay of 50 ps have been experimentally realized and the frequency responses corresponding to the time-delays has been measured. The measured frequency response error at center frequency and the time-delay difference error were 180 MHz at 10 GHz and 3.2 ps, respectively, when the fiber-optic delay line has the time-delay difference of 50 ps.

Tunable Photonic Microwave Delay Line Filter Based on Fabry-Perot Laser Diode

  • Heo, Sang-Hu;Kim, Junsu;Lee, Chung Ghiu;Park, Chang-Soo
    • Current Optics and Photonics
    • /
    • v.2 no.1
    • /
    • pp.27-33
    • /
    • 2018
  • We report the physical implementation of a tunable photonic microwave delay line filter based on injection locking of a single Fabry-Perot laser diode (FP-LD) to a reflective semiconductor optical amplifier (RSOA). The laser generates equally spaced multiple wavelengths and a single tapped-delay line can be obtained with a dispersive single mode fiber. The filter frequency response depends on the wavelength spacing and can be tuned by the temperature of the FP-LD varying lasing wavelength. For amplitude control of the wavelengths, we use gain saturation of the RSOA and the offset between the peak wavelengths of the FP-LD and the RSOA to decrease the amplitude difference in the wavelengths. From the temperature change of total $15^{\circ}C$, the filter, consisting of four flat wavelengths and two wavelengths with slightly lower amplitudes on both sides, has shown tunability of about 390 MHz.

Photonic K-Band Microwave Bandpass Filter with Electrically Controllable Transfer Characteristics Based on a Polymeric Ring Resonator (전기적으로 가변되는 전달특성을 갖는 폴리머 링 광공진기를 이용한 마이크로웨이브 대역통과 필터)

  • Kim, Gun-Duk;Lee, Sang-Shin
    • Korean Journal of Optics and Photonics
    • /
    • v.17 no.5
    • /
    • pp.475-479
    • /
    • 2006
  • An integrated photonic K-band microwave bandpass filter has been proposed and demonstrated by incorporating a polymeric ring resonator. Its transfer characteristics were adjusted by shilling the resonance wavelength of the ring resonator via the thermooptic effect. The achieved performance of the filter includes the center frequency of 20 GHz, the attenuation of ${\sim}15dB$, the bandwidth of 2 GHz, and the corresponding quality factor of 10. The microwave output power within the passband of the device was adjusted at the rate of about 6.7 dB/mW in the range of 27 dB. This kind of device with electrically controllable transfer characteristics can be applied to implement microwave switches and other devices.

Microwave Instantaneous Frequency Measurement (IFM) Approach Based on an Integrated Photonic Ti:LiNbO3 Y Branch

  • Zhang, Changsheng;Zhang, Jiahong;Zhao, Zhengang
    • Current Optics and Photonics
    • /
    • v.4 no.4
    • /
    • pp.361-367
    • /
    • 2020
  • An approach based on an integrated photonic Ti:LiNbO3 Y branch has been proposed, designed, and analyzed for the microwave instantaneous frequency measurement (IFM). By designing the Y branch with length L = 6545 ㎛ and refractive index NTE - NTM = 0.0764, a complementary optical filter with free spectral range (FSR) of 600 GHz is constituted, which results in a maximum measureable frequency of 300 GHz being obtained. Theoretical analysis on the temperature stability of the Ti:LiNbO3 Y branch shows that the FSR variation of the complementary filter is 0.3% for the temperature change of 100 K, which indicates that the IFM approach will have a better stability. All these results demonstrate that the proposed IFM approach has potential capability to be used for the increasingly higher microwave IFM with better stability.

Four-channel Selective Photonic Microwave Filter Based on Optical Resonator Router (폴리머 광공진기 라우터 기반의 4채널 선택 포토닉 마이크로웨이브 대역통과 필터)

  • Kim, Gun-Duk;Eo, Yun-Sung;Lee, Sang-Shin
    • Korean Journal of Optics and Photonics
    • /
    • v.19 no.3
    • /
    • pp.242-245
    • /
    • 2008
  • A four-channel selective microwave filter was demonstrated incorporating an optical resonator router, which is constructed by integrating a $1{\times}4$ space switch with an arrayed ring filters featuring different free spectral ranges. The center frequency of each channel was determined by the FSR of the corresponding ring resonator, and the four channels centered at 10 GHz, 16 GHz, 18 GHz and 20 GHz were individually selected to provide a bandpass filtering via the control voltage applied to the switched resonator.

Sidelobe Suppression Enhancement of Radiofrequency Photonic Filters via Time-to-frequency Mapping

  • Song, Min-Hyup
    • Journal of the Optical Society of Korea
    • /
    • v.18 no.5
    • /
    • pp.449-452
    • /
    • 2014
  • We present a multi-tap microwave photonic filter with high selectivity through applying time-to-frequency mapping and optical frequency comb shaping techniques. When arranged in the time-to-frequency mapping stage, by a Fourier transform, the deviation of the optical taps to the target profile is significantly reduced while maintaining the apodization profile, resulting in high sidelobe suppression in the filters. By applying a simple time-to-frequency mapping stage to the conventional optical frequency combs, we demonstrate a substantially enhanced (>10dB) sidelobe suppression, resulting in filter lineshapes exhibiting a significantly high (>40dB) main lobe to sidelobe suppression ratio. These results highlight the potential of the technique for implementation in various passband filters with high sidelobe suppression.