Abstract: A reference jig comprises a base adapted to be secured to a distal end of a bone. An adjustment mechanism has a bracket, one or more rotational joints operatively mounting the bracket to the base, whereby the bracket is rotatable in two or more rotational degrees of freedom relative to the base, and one or more translational joints. A landmark alignment unit is operatively connectable to the bracket by the at least one translational joint, the landmark alignment unit having a bone alignment component configured to be aligned with at least one bone landmark.

Abstract: A resilient antenna disturbance detector is provided. A signal generator generates an unclonable integrity test signal. The antenna reflects a signal in response to the integrity test signal. A comparator determines whether the reflected signal matches the integrity test signal and a controller signals the disturbance of the antenna to a monitoring device if the energy level of the reflected signal is greater than a predetermined threshold and the reflected signal matches the integrity test signal. The detector provides the advantage of preventing an external receiver and transmitter from predicting and transmitting the integrity test signal to the antenna to interfere with disturbance detection. Also provided is a security system with resilient antenna disturbance detection.

Abstract: A resilient antenna disturbance detector is provided. A signal generator generates an unclonable integrity test signal. The antenna reflects a signal in response to the integrity test signal. A comparator determines whether the reflected signal matches the integrity test signal and a controller signals the disturbance of the antenna to a monitoring device if the energy level of the reflected signal is greater than a predetermined threshold and the reflected signal matches the integrity test signal. The detector provides the advantage of preventing an external receiver and transmitter from predicting and transmitting the integrity test signal to the antenna to interfere with disturbance detection. Also provided is a security system with resilient antenna disturbance detection.