This paper presents the DME (Distance Measurement Error) estimation analysis for the wireless indoor positioning channel. The channel model for indoor positioning is derived and implemented using 8 WLAN (Wireless Local Area Network) antennas system compliant to IEEE 802.11 a/b/g standard. Channel impairments are derived for the TDOA (Time Difference of Arrival) range estimation. DME calculation is performed over distinct experiments in the TDOA channel profiles using 1,2,4 and 8 antennas deployed system. Analysis for the DME for different antennas is presented. The spiral antenna achieves minimum DME in the range of 1m. Data demographics scattering for the error spread in TDOA channel profile is analyzed to show the error behavior. The effect of increase in number of recordings on DME is shown by the results. Transmitter antennas behavior for DME and their standard deviations are depicted through the results, which minimize the error floor to less than 1 m. This reduction is not achieved in the literature to the best of our knowledge.