In order to exploit fully the frequency diversity benefits of multicarrier modulation (MCM), and the very nature of the frequency selective radio channel, we investigate an erasure decoded π/4 QDPSK MCM (ED-MCM) by employing simple Hamming (block) code. We propose the threshold-free criteria, i. e. relative minimum receive power test (RMRPT) and relative maximum decision error test (RMDET) for erasure generation and evaluate ED-MCM's performance by applying these tests to average received power, average decision error, instantaneous symbol/bit decision errors. At a normalized delay spread of 1/64, computer simulation results indicate a coding gains of 6.0 - 7.0 dB with ED-MCM at a BER of 10-3. RMDET/RMRPT based erasure decoding yields a 1.5 - 2.5 dB improvement over the conventional forward error correction (FEC) decoding at a BER of 10-5. The simulation results at other normalized delay spreads, i. e. , 1/32, 1/16 are also obtained. The erasure criteria (RMRPT and RMDET) applied to average values of received power/decision error yield consistently better performance over error only decoding. The results indicate that the erasure decoding based on relative (threshold-free) measures clearly promises an improved performance of the MCM system.