Fig. 1. Schematic diagram of PSK-LFM integrated signal generation

Fig. 2. Constellation and waveform of the signal after DC offset. (a) 8PSK-LFM constellation diagram when DC offset is 1; (b) time domain waveform of 8PSK-LFM with DC offset of 1

Fig. 3. Schematic diagram of the photon-assisted THz-ISAC architecture. (a) Simplified spectrum of the optical frequency comb; (b) simplified spectrum filtered out by the wavelength selector switch; (c) simplified spectrum after modulation by the I/Q modulator; (d) simplified spectrum after the simplified coupling after the frequency tap; (e) simplified spectrum after the frequency tap; (f) schematic diagram of the sensing and communication system architecture

Fig. 4. Simulation results of VPI section. (a) Integrated signal spectrum; (b) linear FM signal spectrum; (c) optical frequency comb spectrum; (d) signal spectrum after coupling

Fig. 5. Ambiguity functions. (a) Ambiguity function for LFM; (b) ambiguity function for 8PSK-LFM

Fig. 6. Time-frequency analysis of the signal. (a) LFM time-frequency analysis; (b) PSK-LFM time-frequency analysis

Fig. 7. Comparison of distance ambiguity functions. (a) Communication rate is 2 Gbaud; (b) communication rate is 4 Gbaud; (c) communication rate is 6 Gbaud; (d) communication rate is 8 Gbaud

Fig. 8. Comparison of spectra after de-chirping at different distance positions. (a) Reference position versus 20 cm from the reference position; (b) reference position versus 0.97 cm from the reference position

Fig. 9. Comparison of geometric shaping gain curves. (a) 8PSK-LFM/GS-8PSK-LFM; (b) 8QAM-LFM/8QAM (star)-LFM/GS-8QAM (star)-LFM

Fig. 10. Received 4 Gbaud 8PSK/GS-8PSK constellation diagram. GS-8PSK-LFM (a) after quadrature normalization; (b) after CMA equalization; (c) after carrier recovery. 8PSK-LFM (d) after quadrature normalization; (e) after CMA equalization; (f) after carrier recovery

Fig. 11. Relation curves of BER and input optical power into PD for 4 Gbaud 8PSK-LFM/GS-8PSK-LFM integrated signal

Fig. 12. Relation curves and constellation diagrams of BER and input optical power into PD for 4 Gbaud GS-8PSK-LFM/GS-8QAM-LFM integrated signals transmitting 50 m wireless distance

Fig. 13. Relation curves of BER and input optical power into PD for 4 Gbaud/8 Gbaud 8PSK-LFM/GS-8PSK-LFM integrated signals transmitting 50 m wireless distance

Fig. 14. Relation curves of BER and input optical power into PD for 8PSK-LFM integrated signal transmission over 10 m wireless distance with different DC components

Fig. 15. BER and PSLR relationship curves of GS-8PSK-LFM integrated signal under different DC components