Signal power estimation in short-range laser radar

In long-range laser radar applications the transmitter and receiver are usually focused at infinity, and the signal power received at any distance can be calculated from the well-known radar equation. The situation is not so simple in short-range applications, however, for here the target image is not always coincident with the sensor in both the axial and vertical directions, and the signal power is not a monotonic function of the measurement range. In view of the uneven distribution of irradiance on both the target plane and the sensor window, the power received cannot be resolved by an analytical expression and is highly dependent on the adjustments of the optics in the transmitter and receiver. This knowledge of the distribution is very important for the design and optimum adjustment of a laser radar system.This paper discusses a mathematical model for calculating the signal power function in relation to target distance and a software package developed for simulating the characteristics of short-range laser radar with fibres as the source and sensor in various adjustment parameters.In long-range laser radar applications the transmitter and receiver are usually focused at infinity, and the signal power received at any distance can be calculated from the well-known radar equation. The situation is not so simple in short-range applications, however, for here the target image is not always coincident with the sensor in both the axial and vertical directions, and the signal power is not a monotonic function of the measurement range. In view of the uneven distribution of irradiance on both the target plane and the sensor window, the power received cannot be resolved by an analytical expression and is highly dependent on the adjustments of the optics in the transmitter and receiver. This knowledge of the distribution is very important for the design and optimum adjustment of a laser radar system.This paper discusses a mathematical model for calculating the signal power function in relation to target distance and a software package developed for simulating the characteristics of short-range...