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The proposition of Time Division Alternative Binary Offset Carrier (TD‐AltBOC) provides a new solution for COMPASS B2 navigation signal.Relative to AltBOC,TD‐AltBOC has higher multiplexing efficiency,lower reception complexity and higher ranging accuracy when greater frontend bandwidth is used.However,the assessment of TD‐AltBOC modulation performance is still in the theoretical period.It is needed to test the properties of TD‐AltBOC actually in the highly realistic and complex spatial simulation environment.To solve this problem,this paper proposes methods of generating TD‐AltBOC signal and simulating the simple multipath scenario on the FPGA‐based hardware platform.TD‐AltBOC is generated using lookup table method based on the basic modulation principles.By converting the value of the parameter k in the lookup table,this paper achieves the key technology that the phase of subcarrier flips with 180 degree at the even chips spot.The multipath signal is composed of direct signal,reflected signal and reference signal.The MDR and multipath delay can be controlled precisely.This article has tested the code tracking performance and anti‐multipath performance of the generated signal.The testing results match the theory.The methods of signal generation and multipath simulation this paper proposes can meet the demand of performance assessment.