似噪音脈衝光纖雷射是由非線性極化演化(nonlinear polarization evolution)之環形共振腔產生，相較於鎖模脈衝，似噪聲脈衝具有周期性，但每個脈衝的電場、強度上有不同的波型。我們可以調控波片的偏振角度，光纖共振腔可以產生鎖模脈衝（MLP）和似噪聲脈衝（NLP）。鎖模脈衝寬度為6.12皮秒，似噪音脈衝的底座寬度、尖端寬度、尖端到底座寬度分別為10.25皮秒、390飛秒、1.34。我們利用脈衝模型來建立鎖模脈衝和似噪音脈衝的自相關曲線和脈衝波型，這兩種自相關曲線與實驗結果大致相同。
根據天線電路模型，我們的模擬利用鎖模脈衝與似噪音脈衝激發電偶極光導天線產生的兆赫波。比較不同雷射激發的兆赫波光譜，鎖模脈衝產生的兆赫光譜頻寬為0.061 THz，似噪音脈衝產生的兆赫光譜頻寬為0.038 THz。似噪音脈衝產生的兆赫光譜可延伸到高頻率(0.2-3 THz)，但是高頻訊號強度小於主訊號50 dB。在相同脈衝能量下，鎖模脈衝產生的兆赫功率為15.8 uW，似噪音脈衝產生的兆赫功率為10~12 uW，似噪音脈衝產生兆赫波的效率沒有比鎖模脈衝產生的較高。

Compared to the mode-locked pulse, the noise-like pulse has periodicity, but the electric field and intensity of its every pulse are different. For our fiber laser system, depending on settings of polarizing components such as the wave plates, fiber lasers can generate both regular mode-locked pulses (MLPs) and noise-like pulses (NLPs). The width of the MLP is 6.12 ps, the pedestal duration, spike duration and peak to pedestal ratio of NLP is 10.25 ps, 390 fs and 1.31, respectively. We use the phenomenological model to construct the AC profiles of MLP and NLPs which is roughly the same as the experimental results.
According to the circuit model, our simulation shows that the THz fields, spectrums, and power of MLP and NLPs excitation from the photoconductive antenna. Compare to the THz spectrum of the MLP excitation, the 3dB-bandwidth of the THz spectrum of NLP excitation (0.05 THz) is narrower than MLP excitation (0.08 THz) at low frequency. The spectrum of NLP as a pump source can extend to a higher frequency (0.2-3 THz), but the signal is very weak. At the same optical pulse energy, the THz power excited by MLP (15.8 uW) is higher than NLP (10~12 uW) excitation and the optical-to-THz efficiency of NLP is not as well as MLP

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