A time slot assignment arrangement for ultralow power devices in a wireless communication network is disclosed. The time slot assigned to ultralow power device wakeup frame is identified as ultralow power timeslot using various indicators. The ultralow power timeslot is assigned as contention based timeslot allowing ultralow power devices in the wireless network to extend the interval for synchronizing with the network overcoming the short synchronization interval requirements of wireless communication network resulting in significant improvement in battery life by preserving the power needed for frequent synchronization with the wireless communication network.