The efficient utilization of the air interface in the LTE standard is achieved through a combination of subcarrier allocation schemes, adaptive modulation and coding, and transmission power allotment. The scheduler in the base station has a major role in achieving the required QoS and the overall system performance. The resources for both downlink and uplink transmission need to be assigned such that the capacity, throughput, and cell edge performance are optimized. This paper investigates allocation schemes for downlink transmission based on different criteria and performs evaluation through simulation results. The system for downlink scheduling is modeled using OPNET Modeler.