Research Of Channelized Receiver Technology Using The Photonic Method

With the rapid development of information technology and continuous improvement, the signal environment is becoming more and more complex. Its frequency range is wider. And maybe multiple signals arrive at the same time. Channelizer is an effective way of receiving the broadband radio frequency(RF). The traditional approach is achieved in the electric field. It requires lots of components, so that the device is often complex and bulky. And it cannot satisfy the increasing bandwidth requirements. The method of photonics has many advantages, such as large bandwidth, light quality, low loss, anti-electric magnetic field interference, and so on. These advantages make it solving the "electronic bottleneck problem". In this paper, one photonic channelized receiver based on four wave mixing(FWM) and periodic filter is researched, using the photon link and the channelized technology. The complexity of channalizer is greatly reduced. The flexiblity is verified by tuning some key parameters, compensating the drawback of filters. In addition, the scheme works in positive mode, thus eliminating the needless insertion loss of the passive components. The main content of this paper is presented as follows:1) The multicast system of signals based on FWM effect in optical fiber is simulated. The results show that single Radio Frequency(RF) signal carried digital signals is multicast successfully using this multicast system. Then the third-order intermodulation distortion of the system is analyzed using the method of continuous dual tone. The output power of copies curve is varied linearly along with the input power of RF signal. Compared with back-to-back third-order intermodulation point, copies of the third order intermodulation intercept point have a low fluctuation in a small scale. So, the system could be used in multicasting of the RF signal with low distortion in a linearly way.2) The photon channelized receiver system based on FWM effect in optical fiber simulation analysis is simulated. The theory of intensity modulation using Mach-Zehnder Modulator is briefly analyzed. Then, the simulation system of the photon channelized receiver is setup in the simulation software named Optisystem. Four copies are selected for analyzation. The results show that this system achieved the purpose of channelized receiver using one periodic filter.3) On the basis of the theory and simulation analysis, the experimental system is set up. The influence of power and wavelength interval between two input lights is tested. When the wavelength interval between the two pumps is fixed, FWM happens easily by increasing the power of pumps. In this case, we can observe more converted light in the output spectrum. With the same other conditions, we change the wavelength interval between the two pumps. Results indicate that small wavelength interval is beneficial to FWM. When the signal wave with low power is input into this system, five copies were generated. And less than 2.5 dB power ripple between the copies was measured. When the signal wave was modulated with one microwave source of 10 GHz, four copies also carried the information of signal wave.