Methods, systems, and devices for guiding surgical instruments using radio frequency technology

Methods, systems, and devices are provided for guiding surgical instruments using radio frequency (RF) technology. In general, the methods, systems, and devices can allow a trajectory, e.g., an angular approach, of a surgical instrument relative to a patient to be identified during use of the instrument in a surgical procedure being performed on the patient. The trajectory can be identified using a plurality of RF modules. The methods, systems, and devices can allow the trajectory to be compared to a predetermined trajectory so as to identify whether the trajectory matches the predetermined trajectory. A result of the matching can be communicated to a user of the instrument. Based on the result, the user can maintain the trajectory, e.g., if the trajectory matches the predetermined trajectory, or can adjust the trajectory to closer align the trajectory with the predetermined trajectory, e.g., if the trajectory does not match the predetermined trajectory.