有限振幅失真現象導致波型失真會產生許多原本沒有的頻率成份，組織諧波影像的諧波信號便是這樣產生的。三倍頻發射相位法可藉由外加一個可改變相位的三倍頻信號而產生頻率和及頻率差的諧波成分來抑制與增強組織諧波信號以改善諧波影像品質。如何用適合的探頭作出所要的功能，在組織諧波中由於諧波訊號是由非線性現象所產生，所以其訊號強度是較基頻訊號微弱，所以要增強諧波影像的強度，但是由於探頭的頻寬限制，要在單一探頭產生不同的頻率，或接收2倍頻的頻率都會受到探頭的頻寬的影響，所以要如何作出適當的探頭就很重要。
在本研究中，經由模擬確認三倍頻相位法於單一陣列式探頭實現的可能性，但是在研究中發現單一陣列式探頭中由於基頻與三倍頻設計於探頭中不同通道時，由於空間上的差異，並無法得到很好的空間解析，能解決此一問題的方法為使用多通道陣列式探頭，於相同半徑環型陣列式探頭中通道越多則空間解析越佳。

The Finite amplitude distortion will be let waveform distortion caused many not originally produce the frequency components. Tissue harmonic imaging is the product of such harmonic signals. The method of third harmonic (3f0) transmit phasing utilizes an additional 3f0 transmit signal to provide mutual cancellation and addition between the frequency-sum component and the frequency-difference component of tissue harmonic signal. Appropriate to the desired function of probe. In tissue harmonic signals, because non-linear phenomenon of harmonics. So the signal strength is weak compared with the baseband signal, so images to enhance the harmonic intensity However, due to bandwidth limit the probe to produce different probes in a single frequency, or receive Second harmonic frequency bandwidth will be the impact of the probe, so how appropriate it is important to the probe.
In this study, the simulation confirmed that the third harmonic phase method on a single array probe the possibility of achieving. However, the study found that a single array probe in the fundamental frequency and third harmonic design of the different channels in the probe, due to differences in space, and can not be very good spatial resolution. To solve this problem for the use of multi-channel array probes and the same radius of the annular array probe in the channel the more the better in the spatial resolution.

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