i am trying to design a robot which can track a transmitter which produces rf signals in a given range of frequencies(example:- 400-900 MHz). i want to know the following details. 1. i have a design of wireless robot with A433MHz RF modules. i need to change the frequency of transmission without changing the main components like antenna(assume the tracking frequency is within the antenna' bandwidth).is it possible to design such transmitters and receivers in RF range. Then how to choose the antenna types for such designs if possible. 2. i plan to train it initially to a particular frequency in the given range which is supposed to be my training phase. then the robot should track my transmitter's change in frequencies within lock in range and should be used for finding the transmitter's location.i plan to have a buzzer which sounds when the bot reaches say within 1 meter radius of the transmitter. 3.please suggest me some key concepts and prerequisites for my extensive reading to implement this stuff. 4. suggest me the feasibility of this design like how far this is possible for implementation. if not what are the modifications needed. thank you all.