Photoconductive antenna (PCA) is one of the most used terahertz (THz) radiation sources in terahertz time domain spectrometry (THz-TDS) system. In this paper, a 1560nm laser-excited fiber-coupled terahertz radiation source module is designed and simulated using InGaAs/InAlAs superlattice PCA chip based on the principle of terahertz signal generating by PCA. Through the integrated design of optical path and structure, the miniaturized terahertz radiation source is obtained. Under the excitation of femtosecond pulse laser with an average power of 25mW, pulse width of 100fs and central wavelength of 1560nm, THz signal with the spectral range of 0.1~2.9THz and the dynamic range of 57dB obtained is achieved from sampling of single waveform of terahertz radiation source. In addition, the excitation light power, the bias voltage and the relationship between the output signal amplitude of the terahertz radiation source is investigated experimentally.