Radar measurement accuracy: The accuracy of radar measurement of a single target parameter is related to many factors, such as the completeness of the radar system itself, radio wave propagation, etc. Here, we only discuss the maximum measurement accuracy that radar can provide in the presence of noise.

Radar resolution: The ability of a radar to distinguish a specific target from two or more targets. It is related to the characteristics of the radar itself, target characteristics, etc. Here, only the inherent resolution related to the radar transmission waveform is studied.

Radar measurement accuracy and resolution are important indicators of radar system performance, which directly affect the radar's ability to detect and identify targets. This article will delve into these two concepts and the key factors that influence them.



Radar measurement accuracy refers to the accuracy of a radar system in measuring individual target parameters such as distance and velocity. In practical applications, radar systems are affected by various factors such as noise and radio wave propagation conditions. Especially in noisy environments, the echo signals received by the radar will produce distortion, leading to measurement errors. The mean square error criterion is a method for evaluating accuracy, which determines the magnitude of the error by calculating the mean square error between the transmitted signal and the mixed waveform of the echo signal and noise. The measurement time error is closely related to factors such as the signal-to-noise power ratio and the root mean square bandwidth of the signal, and the root mean square error is proportional to these parameters.

The accuracy of radar speed measurement involves the precision of measuring the target's motion speed using radar. Similarly, the presence of noise can affect the measurement results, leading to measurement errors in speed. The root mean square time width and measurement frequency error are indicators of this accuracy, which are related to the nonlinear phase characteristics of the signal. The nonlinear phase variation of the signal will further affect the speed measurement accuracy. Through the formula, it can be found that the relationship between nonlinear phase characteristics and measurement accuracy is nonlinear.

Radar resolution involves the ability to distinguish specific targets from multiple targets, mainly divided into distance resolution and velocity resolution. Distance resolution refers to the ability of a radar to distinguish between two closely adjacent targets, which depends on the distance autocorrelation function of the signal. The width of the main peak of the autocorrelation function determines the resolution, which is usually represented by the time width corresponding to the distance from the main peak of the autocorrelation function to a certain level. Gaussian envelope frequency modulated or non frequency modulated signals have optimal distance resolution. On the contrary, when the high-frequency phases are close, the resolution will decrease.



Velocity resolution measures the ability of a radar to distinguish between two targets with small velocity differences, which depends on the Doppler frequency autocorrelation function of the signal. The Doppler resolution constant is inversely proportional to velocity resolution, meaning that the higher the resolution, the smaller the velocity difference that can be distinguished. The improvement of speed resolution can be achieved by increasing the signal duration or reducing the bandwidth of the transmitted signal.

Radar measurement accuracy and resolution are core considerations in the design and optimization of radar systems. Improving accuracy and resolution requires comprehensive consideration of various components of the radar system, including the type of transmitted signal, bandwidth, noise level, and signal processing technology. By optimizing these parameters, more accurate and refined target detection and tracking can be achieved, thereby improving the overall performance of the radar system.