The use of multiple packet reception (MPR) can alleviate congestion in multi-hop networks and improve network Goodput. However, a sophisticated design is required in order to enable MPR in such networks considering the heterogeneity of transiting packets, both in size and arrival times. In this paper, we introduce a cross-layer MPR-PHY/MAC design suitable for multi-hop ad-hoc networks. Our design identifies three phases of operation tied to the network offered load. Simulation results show that the saturation Goodput of a network using our proposed MPR-PHY/MAC design is better than that of a network using standard IEEE 802.11 PHY and MAC by a factor of at least $50\%$.