Frequency diverse array (FDA) is referred to an array transmitting linearly increasing carried frequencies across the array elements. Compared to traditional phase-arrays (PA), the difference in multi-frequency characteristics will result in that the effective signal-to-noise ratio (SNR) changes with time, angle and distance. This paper also demonstrates that the S-NR of FDA is does not outperform PA under the same conditions in most of time. The decrease of SNR will greatly degrade the estimation accuracy of Frequency Different of Arrival (FDOA) and Time Different of Arrival (TDOA). The significantly degraded FDOA and TDOA estimation accuracy will make the intercepted emitter position being significantly deviated from its actual position, which also means the achievement of localization deception capability.