1. A receiver for a real time locating system (RTLS), comprising: a down converter converting a signal into a base band signal; a matched filter matched-filtering the converted base band signal; an adaptive transversal filter (ATF) estimating an interference signal with an output of the matched filter, and filtering the output to remove interference of a heterogeneous signal of the same frequency band; a de-spreader multiplying an output of the ATF and a code according to direct sequence spread spectrum (DSSS) modulation used for spreading when a tag signal is modulated, and performing chip-matched filtering on the output from the ATF and obtaining a value of correlation energy through a de-spreading process; and a detector detecting transmission data using the correlation energy value, where the filtering is implemented according to a weight generated in correspondence with the interference signal estimated and an input value, and the signal is demodulated using the code.