Abstract: Weak target detection has always been an important challenge for airborne radar, and a target interframe noncoherent integration and detection method is proposed in this paper. Firstly, the airborne radar signal model when multiple frames using different carried frequencies and pulse repetition interval is build. Secondly, a method of the moving target Doppler correction and the range migration compensation is proposed, which makes the target between different frames in the same cell to be detected. Then, the strong targets are detected and deleted, range cycle expansion is used to resolve range ambiguity, and interframe noncoherent integration is applied. After processing by the proposed method, the detection performance for weak target is improved. Finally, simulation result is given to prove the effectiveness of the proposed algorithm.