In this paper, we propose a scheme for optical generation and application of chirp polarity-modulated LFM signal. Furthermore, we generate an LFM signal with quadrupled carrier frequency and bandwidth, whose chirp polarity is controlled by input binary sequqence. The simulation results verify the feasibility of the scheme in frequency-multiplied signal generation, measurement of Doppler frequency shift, and wireless communication. Additionally, we input 4-6 GHz, 5-6.5 GHz, 8-9 GHz LFM signals, generating 16-24 GHz, 20-26 GHz, and 32-36 GHz triangular frequency-modulated signals, respectively, whereas the time-bandwidth product is expanded seven times. Also, the generated signal realizes the speed measurement of a moving target at a speed of 800 m/s. The ambiguity function is used to analyze the performance of the signal on solving the range-Doppler coupling problem. Besides, for wireless communication, the matching filter at the receiving end successfully recovers the 10-bit binary sequence with a code rate of 0.1 Gbit/s. This scheme combines chirp polarity modulation and optical microwave frequency multiplication, thereby generating a triangular wave frequency modulation signal for the joint measurement of radar speed and distance, improving radar detection resolution, and enlarging the chirp modulation usage scope to realize the integrated application of radar communication.