In the existing two-dimensional direction-of-arrival (DOA) estimation algorithms based on spectral peak search

the complexity is high and the accuracy is greatly influenced by the search interval.To overcome these problems

this paper examines a two-dimensional DOA estimation with coprime rectangular array using bi-directional propagator method

which realizes a low complexity

high accuracy

unambiguous for 2-D estimation.Firstly

this algorithm introduces coprime array into 2-D DOA estimation

and constructs a coprime rectangular array model.The two rotation factor matrices along the different directions for propagator method can be got

the elevation angle and azimuth angle for the sources can be obtained from the rotation factor matrices.Further more

the multi values of sparse array are eliminated by using coprime theory

and the proof of unambiguous for two-dimensional DOA estimation under the coprime array model is provided.This paper also analyzes the complexity and gives the Cramer Rao lower bounds (CRB) of coprime rectangular array.Theoretical analysis and simulation results show that this algorithm does not need to angle matching and spectrum peak search

under the same conditions

the root mean square error (RMSE) performance is better than the multiple signal classification (MUSIC) algorithm of uniform rectangular array.At the same time

the proposed algorithm can reach the same accuracy of high dimensional grid search with low complexity and without ambiguity.