Abstract: An adaptive signal level detector. The inventive detector includes a first circuit for receiving an input signal and providing a second signal identical to said input signal and delayed relative thereto. The amplitude of the delayed signal is compared to the maximum amplitude of the input signal. When the second signal is at a predetermined level relative to the input signal an output signal is provided. In a specific implementation, the invention (10) includes a first circuit (18) for detecting the signal level of the transmitted signal and providing a second signal in response thereto. The second signal is a logarithmic representation of the input signal The second signal is delayed (20) to provide a third signal. The third signal is subtracted (24) from the second signal to provide a fourth signal. When the fourth signal exceeds a predetermined threshold, an output signal is provided.

Abstract: A time code receiver 18 is used to provide a rough estimate of an elapsed time, which is then enhanced by additional circuitry 53. The time code receiver 18 uses a square wave reference oscillator to produce a digital time value 56. This reference oscillator is also fed into a phase detection circuit 34 along with an output 30 from a second oscillator circuit which is triggered upon detection of the occurrence of the event 24. The measured phase difference of the time code receiver reference oscillator 20 and the second oscillator signal 30 is used to produce digital values 38 and 40 that represent a fraction of the clock cycle. This fractional clock cycle or "fine time" value is added to digital time value 56 from the time code receiver 18 to increase the resolution of time measurement. This method of measuring times of events can be used to measure events such as the arrival of radio frequency signals at remotely based receivers in order to determine the distance of the transmitter from the receivers.

Abstract: RF energy radiated by impacting munition rounds is used to provide an indication to a gunner where the rounds from his gun are striking, or to control a gun servo (158) to automatically correct the aiming of the gun. The RF energy from the rounds is received by several antennas (32, 34, 36) in a known geometry and the angle of arrival computed from the differences in the times of arrival at each antenna. The impact locations can be displayed in the existing gun sight, or in a head up display for the gunner. The angle of arrival information can further be used to control a gun aiming servo (158) to correct the aim of the gun to improve accuracy.

Abstract: An improved power supply (10) for an electrical circuit (12) mounted on a projectile. The inventive power supply (10) includes a mechanism (14) on the projectile for generating electrical energy on the acceleration thereof. The energy is stored and released to a load on the deceleration of the projectile. In a particular implementation, the energy producing mechanism (14) is a piezo-electric transducer. Storage of electrical energy in the transducer is facilitated by the connection of a diode (16) across the output terminals thereof. An acceleration switch (18) is provided which is mounted on the projectile to be open on acceleration and closed on deceleration thereof. The switch (18) thereby releases a predetermined amount of stored energy to the load (12) only on the impact of the projectile with an object.

Abstract: A munition incorporating a miniature transmitter (25) and a piezoelectric power supply (45) which converts a portion of the kinetic energy of the projectile (20), upon impact, into radio frequency energy and radiates that energy into space. The transmitter (25) can be made in suitable sizes to fit various calibers of ammunition. Different caliber ammunition can be made to radiate different frequencies. The transmitted RF energy allows the point of impact of the projectiles to be located with a high degree of precision. This type of munition may be used in the scoring of air to ground gunnery in training environments by receiving the RF energy at several known locations and determining the point of impact using time of arrival or angle of arrival techniques. Frequency discrimination allows simultaneous scoring of multiple weapons from the same aircraft or from multiple aircraft. The munition may be employed in tactical applications by allowing the fall of fire to be located and adjusted.

Abstract: An analog system (100) of measuring the difference in time of occurrence of events. The method uses two coherent oscillators (110, 116) of the same frequency which start with predetermined phase when each of the events are detected. The phase difference of the oscillators (110, 116) is a measure of the difference in the time of occurrence of the two events.