Orthogonal code-hopping multiplexing (OCHM) is a statistical multiplexing scheme designed to increase the number of allowable downlink channels in code-division multiple-access (CDMA) systems. OCHM makes it possible to use orthogonal code resources more efficiently than the conventional dedicated codeword allocation/multiplexing schemes in cdma2000 and wideband DMA(WCDMA) systems. Collision-allowable hopping in the OCHM system yields a statistical multiplexing gain. However, collisions may degrade the bit error rate (BER) performance. A group-mode hopping scheme is proposed as a collision mitigation scheme for OCHM. The performance of the proposed scheme is evaluated using numerical analysis and simulations.