Nowadays, in addition to having a key role in some sensitive situations such as military and disaster applications, wireless communication has become a part of human life. Indeed, in many advanced countries, communication products such as mobile, WLAN, GPS, RFID have become a part of human life. Moreover other applications like wireless sensor networks or remote telemedicine have propounded. Increasing demand for low-cost, low-power, low-size and high operating frequency wireless components has caused rapid growth of wireless communication. Frequency synthesizers are one of the main parts in any transceiver and frequency divider block is an essential part of the synthesizer. In UWB systems and CR which cover a wide frequency range, a set of frequency dividers are put at the output of frequency synthesizer. The output of these frequency dividers should cover a wide range of operating frequency. Frequency dividers based on D-flip-flop are usually used at low frequencies. But, at high frequencies, digital methods for frequency dividing are not suitable. This is because they consume significant power moreover their correct division function fails at high frequencies. Therefore analog methods are usually used for high frequency applications. Injection-Locked Frequency Dividers (ILFDs) are analog dividers which have the merit of high operating frequency and low power consumption. These dividers can divide frequency by even or odd numbers. ILFDs with even division factor have recently received more attention and analytical models appropriate for circuit design have been developed but dividers with odd division factor have been studied less. Problems such as having a narrow locking range or having non-quadrature outputs are some issues in these dividers. The need for using frequency dividers with odd division factor can be felt in low power prescalars or communication systems such as UWB and Cognitive Radio. ILFDs can be stroked="f" filled="f" path="m@4@5l@4@11@9@11@9@5xe" o:preferrelative="t" o:spt=" Keywords: 1-local oscillator 2-injection locked frequency divider (ILFD) 3-odd division factor 4-wide locking range 5- quadrature input-quadrature output
