Abstract:A novel sparse linear array geometry, i.e. a new nested array, is proposed based on KhatriRao (K-R) subspace , which is capable of increasing the degrees of freedom (DOF) of arrays. The new nested array consists of two uniform linear arrays (ULA), where the spacing of larger ULA is determined by the array length of smaller one. Compared with a ULA providing DOF with sensors, a new nested array is able to increase the DOF to by obtaining a virtual ULA with sensors through KR product in K-R subspace, and thus the increased DOF makes it possible to resolve more sources. In addition, the new nested array is a sparse array, and has longer aperture than that of ULA in equal number of sensors to bring a good ability to resolve nearby targets. The new nested array is one of the arrays, which have the largest DOF increased by K-R product, and the performance of the new nested array is good even under the condition of low SNR and small snapshots.