An oscillator is required for generating the periodic signal with constant frequency, phase, and amplitude. Tunable oscillator can generate multiple frequency signals in the specified range. Here a tunable oscillator is designed for covering a good range of microwave and radio frequency (RF) spectrum. The tunable oscillator which is developed here using single HEMT for 5GHz to 5.2GHz can be used for multiple wireless applications. The quality of this design such that it can generate a band of 200MHz frequency. By using this oscillator, multiple devices can be operated in the range of 5GHz to 5.2GHz. In this design, oscillator characteristics are optimized to meet the specified IEEE standards. Commercially available simulation tools ADS and EMDS are used in the modeling of this novel device.