Author: Dr. Dao Chi Thanh

Faculty: Vietnam National University, Hanoi

Country: Vietnam

e-mail: Pqnguyen77@yahoo.com

The radar transmits a variable elliptical polarization signals, the reflected signals from the targets are  received and processed in 2 receiver channels, the output signal from the 2 receiver channels is processed by weighted, multi-dimensions special algorithms – formulas for getting the highest detection probability.


1-This technology can detect very small tagets with the RCS small to 0.01 m2  , and the potencial even smaller than 0.01 m2;

2-Displaying only 1 color will choose a variant to get better ability to detect the target class of that color;

3-Changing the color assignment scheme will select the color assignment plan for better target detection and classification;

4-Very good background noise supression;

5-Capable of detecting targets in the woods (forest) because the Jαβ of the target is different from Jαβ  of the woods;

6-Base on Jαβ we can classify and identify targets by creating a library of Target Types of Parameters Jαβ to defind target identification and classification, this is a very important issue in radar engineering.

Radar transmits an elliptical polarized signal of the form  i : e i T,  ( i  is positive integers in the range [1 ÷ I ], I is any positive integer that takes value in the range [1 ÷ +∞ ) (1) ), the elliptic signal i reflected from the target e i R  can be  decomposed on the union of  2 circularly polarized signals: right circular polarization and left circular polarization having different amplitudes which are received and processed in 2 receiver channels; the output signals from receiver channels 1, receiver channel 2 are E i1 , E i2  ;  E i1 , E i2   are sent to the Signal Processing System and then sent to the Digital Signal Processing System to compute:

–         Iiαβ =  (2) is the Weighted Ratio (WR) of E i1 , E i2 ; α, β are positive integers (in the general case will be plural) in the range [1 ÷ M], M is any positive integer that takes value in the range [1 ÷ +∞ ) (3).

–         Weighted Radar Cross Section (WRCS) of the target is computed:

   Ϭiαβ =    Ϭiαβ ( α, β,  )     (4)

–             Jiαβ = Jiαβ ( Iiαβ )   (5)

Jiαβ is the coefficient reflecting the Weighted Eigenfeatures (WE) of the target.

Jiαβ will be in the range [-a, +a]   (6),  a is a definite positive integer,  range [ -a, +a ]  is divided into N segments, N is a positive integer  in the range [1 ÷ 100 ) (7), each segment is assigned a color so in the range [ -a, +a ]  there are N segments corresponding to N colors, each color corresponds to a target class with the same  Jiαβ  value.  Jiαβ , Ϭiαβ will be taken to a 2-dimensional display: color type, color brightness; Jiαβ determines the color type, which is the color of the target marker;  Ϭiαβ determines color brightness, which is the brightness of the target marker  (8).

The number of color types N is enough to be easily distinguishable by the eye, in the case of auto-detection using Artificial Intelligence (AI) technology, the number of color types that can be selected is large enough to satisfy the target marker resolution.

For each set of values α , β we have a pair of values Jiαβ , Ϭiαβ , for each pair of Jiαβ , Ϭiαβ we have a value of  PDiαβ ( Target Detection Probability ); then we will have the value PDimax = Max { P Diαβ }; α, β = [ 1,…,M]  (9), so we have a pair of α , β for the PDimax for each signal type elliptic polarization ei – PD is a most important parameter  of radar.

The transmitted signal is parameterized to have ellipses of the form i (i = [1…I],  then we have PDmax max = Max {PDimax }  (10) i= [1…I], which is the highest Detection Probability P Dhighest   =  P Dmax max                  (11).

Set of Algorithms – Formulas (1), (2), (3), (4), (5), (6), (7), (8), (9), (10), (11) have implemented a weighted processing variable elliptical polarization radar signal in 5-dimensional space: α , β , Jαβ , Ϭ αβ , and time t give the highest Detection Probability. It is called “Weighted, multi-dimentional processing of variable eliptical polarization radar signal for  highest Detection Probability”.

          With this set of Algorithms – Formulas, we will not only choose the set of parameters α , β for the highest Detection Probability, but also base on Jαβ we can establish a library of Parameters Jαβ – Type targets to be able to identify and categorize targets. This is a very important issue in radar engineering.

In fact, we can have a very simple way of implementing the above Algorithms-Formulas: With the parameters I, M, N, α, β selected defined, the 2 important parameters Jαβ, Ϭαβ are computed while the radar continuously transmits e i T and brought them ( Jαβ, Ϭαβ ) to the display.