Wireless network is a network of computers, computer peripherals and various other devices that are connected to each other without wires. This enables ease of communication, especially for mobile computing platforms. WiMAX (Worldwide interoperability for Microwave Access) is the latest contender as a last mile solution for providing broadband wireless Internet access and is an IEEE 802.16 standard. In IEEE 802.16 MAC protocol, BandWidth Request (BWR) is the mechanism by which the Subscriber Station (SS) communicates its need for uplink bandwidth allocation to the Base Station (BS). The performance of the system is affected by the collisions of BWR packets in uplink transmission, that have the direct impact on the size of the contention period in uplink sub frame, uplink access delay and uplink throughput.