In the modern military conflict，the optoelectronic countermeasure technology has been more and more widely used，and concealment is also an important part of the warplanes，which can not be ignored. Due to the launch of electromagnetic wave ranging is easy to leak their own position，single station passive or passive positioning technology has many advantages such as small size，good concealment and high mobility，so it has an important application prospect in modern war. In this paper，in accordance with the idea of positioning before ranging，from the perspective of single airborne passive positioning algorithm，the differences between the proposed method and the traditional passive ranging method in terms of solving speed and accuracy are compared and analyzed by establishing three kinds of geometrical models under the geodetic coordinate system. By modeling and designing the actual application scenarios of airborne targets，the two algorithms are respectively used to solve the effective return distance values after filtering the pitch angle at an altitude of 4 000 m and a solving frequency of 500 Hz. The experimental comparisons result in a significant reduction in the computational complexity of the proposed passive positioning algorithm compared with the traditional passive ranging methods，and an increase in the average solving time of about 56.91%，which greatly increases the frequency of solving the airborne targets and saves more computational resources at the same time. It greatly increases the frequency of on-board target solving，saves more computational resources，and also ensures the stability of positioning accuracy，which can meet the requirements of practical use.