Frequency upconversion of multiple RF signals using optical carrier suppression for radio over fiber downlinks.

We propose and analyze a technique of an optical carrier transmitting two RF signals using optical carrier suppression. A single optical Mach-Zehnder modulator is used for both optical carrier suppression and signal modulation, and optical carrier suppression modulation is also used for frequency conversion of RF signals. This work shows that in contrary to the case of an optical carrier transmitting a single RF signal with optical carrier suppression where stronger optical carrier suppression improves the upconverted RF signal, weaker optical carrier suppression is preferred for an optical carrier transmitting two RF signals due to nonlinear distortion because the nonlinear distortion is reduced by using weaker optical carrier suppression. We find that the usable range of optical carrier suppression ratio is from 10 to 18 dB for RF signal upconverted to 20 GHz and beyond, and the best optical carrier suppression ratio is around 10 dB. We verify the concept and analysis with experiment. In experiment, we used two RFs at 6 and 18 GHz transmitting two 750 Mb/s signals. The experiment for the first time demonstrated that an optical carrier can transmit two RF signals using optical carrier suppression and showed that upconverted RF signals are degraded by nonlinear distortion, particularly for upconverted RF signal at 12 GHz, i.e. the RF signal at the lower frequency.

[1]  A. Nirmalathas,et al.  Dispersion-tolerant multiple WDM channel millimeter-wave signal generation using a single monolithic mode-locked semiconductor laser , 2005, Journal of Lightwave Technology.

[2]  A. Nirmalathas,et al.  Simultaneous multiplexing and demultiplexing of wavelength-interleaved channels in DWDM millimeter-wave fiber-radio networks , 2006, Journal of Lightwave Technology.

[3]  A. Nirmalathas,et al.  Hybrid Multiplexing of Multiband Optical Access Technologies Towards an Integrated DWDM Network , 2006, IEEE Photonics Technology Letters.

[4]  Effect of third-order intermodulation on radio-over-fiber systems by a dual-electrode Mach-Zehnder modulator with ODSB and OSSB signals , 2006 .

[5]  Ke Wu,et al.  A novel millimeter-wave-band radio-over-fiber system with dense wavelength-division multiplexing bus architecture , 2006, IEEE Transactions on Microwave Theory and Techniques.

[6]  Xiupu Zhang,et al.  A novel single wavelength balanced system for radio over fiber links , 2006, IEEE Photonics Technology Letters.

[7]  Xiupu Zhang,et al.  Millimeter-Wave Photonic Techniques for Broadband Communication and Sensor Applications , 2006, LEOS 2006 - 19th Annual Meeting of the IEEE Lasers and Electro-Optics Society.

[8]  L.P. Barry,et al.  Remote downconversion with wavelength reuse for the radio/fiber uplink connection , 2006, IEEE Photonics Technology Letters.

[9]  Lin Chen,et al.  A Radio-Over-Fiber System With a Novel Scheme for Millimeter-Wave Generation and Wavelength Reuse for Up-Link Connection , 2006, IEEE Photonics Technology Letters.

[10]  Peng-Chun Peng,et al.  Simultaneous Generation of Baseband and Radio Signals Using Only One Single-Electrode Mach–Zehnder Modulator With Enhanced Linearity , 2006, IEEE Photonics Technology Letters.

[11]  Xiupu Zhang,et al.  Impact of nonlinear distortion in radio over fiber systems with single-sideband and tandem single-sideband subcarrier modulations , 2006 .

[12]  T. Kuri,et al.  Wavelength-division-multiplexed Millimeter-waveband radio-on-fiber system using a supercontinuum light source , 2006, Journal of Lightwave Technology.

[13]  Ke Wu,et al.  Phase-Noise Analysis of Optically Generated Millimeter-Wave Signals With External Optical Modulation Techniques , 2006, Journal of Lightwave Technology.

[14]  Ke Wu,et al.  Efficient Photonic Generation of Millimeter-Waves Using Optical Frequency Multiplication in Radio-over-fiber Systems , 2007, Microwave Photonics, 2007 Interntional Topical Meeting on.

[15]  Lin Chen,et al.  A Novel Radio-Over-Fiber System With Wavelength Reuse for Upstream Data Connection , 2007, IEEE Photonics Technology Letters.

[16]  Hai-Han Lu,et al.  Bidirectional Radio-Over-DWDM Transport Systems Based on Injection-Locked VCSELs and Optoelectronic Feedback Techniques , 2007, IEEE Photonics Technology Letters.

[17]  A.M.J. Koonen,et al.  Microwave Signal Generation and Transmission Based on Optical Frequency Multiplication With a Polarization Interferometer , 2007, Journal of Lightwave Technology.

[18]  Peng-Chun Peng,et al.  Hybrid Optical Access Network Integrating Fiber-to-the-Home and Radio-Over-Fiber Systems , 2007, IEEE Photonics Technology Letters.

[19]  Xiaoping Zheng,et al.  A Radio-Over-Fiber Downstream Link Employing Carrier-Suppressed Modulation Scheme to Regenerate and Transmit Vector Signals , 2007, IEEE Photonics Technology Letters.

[20]  Ting Wang,et al.  A Novel Radio-Over-Fiber Configuration Using Optical Phase Modulator to Generate an Optical mm-Wave and Centralized Lightwave for Uplink Connection , 2007, IEEE Photonics Technology Letters.

[21]  A. Nirmalathas,et al.  Investigation of Performance Enhancement of WDM Optical Interfaces for Millimeter-Wave Fiber-Radio Networks , 2007, IEEE Photonics Technology Letters.

[22]  Ting Wang,et al.  Centralized Lightwave Radio-Over-Fiber System With Photonic Frequency Quadrupling for High-Frequency Millimeter-Wave Generation , 2007, IEEE Photonics Technology Letters.