In this contribution a novel Frequency Coded (FC) chipless RFID system is introduced to significantly enhance the tag detection. The proposed system exploits the properties of Pseudo Noise (PN) random sequence, as a transmitted signal, to accurately estimate the Channel Impulse Response (CIR). Consequently, the undesired environmental clutter is filtered by a Selective-RAKE receiver. Hence, the tag is accurately identified in a heavily dense multipath environment using neither reference tags for calibration nor the non-practical no-tag deduction process. A real world simulation, based on ray-tracing tool is performed for to verify the system performance. Furthermore, the system testbed is realized on Software Defined Radio (SDR) platforms, where the tag detection is achieved with minimum latency and optimal precision.