초록 ▼

An apparatus for detecting at least one tone having a known frequency and duration in an input signal. The input signal is input over a period of time which is divided into frame portions including at least an initial frame portion and a last frame portion. An energy signal indicative of the energy

An apparatus for detecting at least one tone having a known frequency and duration in an input signal. The input signal is input over a period of time which is divided into frame portions including at least an initial frame portion and a last frame portion. An energy signal indicative of the energy of the input signal during each frame portion is generated. A signal filter receives the energy signal and generates a noise indicator for each frame portion based on whether noise is detected in the energy signal. A dynamic threshold determiner generates an energy threshold for each frame portion. The energy threshold for the initial frame portion is generated based on a minimum expected value of the energy signal for a subsequent frame portion. The energy thresholds for frame portions subsequent to the initial frame portion are generated based on values of the energy signals during previous frame portions and the noise indicator. A signal processor determines when the input signal includes the at least one tone based on the energy threshold, the noise indicator, and the energy signal.

대표청구항 ▼

An apparatus for detecting at least one tone having a known frequency and duration in an input signal. The input signal is input over a period of time which is divided into frame portions including at least an initial frame portion and a last frame portion. An energy signal indicative of the energy

An apparatus for detecting at least one tone having a known frequency and duration in an input signal. The input signal is input over a period of time which is divided into frame portions including at least an initial frame portion and a last frame portion. An energy signal indicative of the energy of the input signal during each frame portion is generated. A signal filter receives the energy signal and generates a noise indicator for each frame portion based on whether noise is detected in the energy signal. A dynamic threshold determiner generates an energy threshold for each frame portion. The energy threshold for the initial frame portion is generated based on a minimum expected value of the energy signal for a subsequent frame portion. The energy thresholds for frame portions subsequent to the initial frame portion are generated based on values of the energy signals during previous frame portions and the noise indicator. A signal processor determines when the input signal includes the at least one tone based on the energy threshold, the noise indicator, and the energy signal. e Current Touchdown Point and Intended Touchdown Point position and elevation. 21. The apparatus of claim 19, further comprising a source of host aircraft configuration, thrust, and trajectory data; wherein the processor is further coupled to receive the aircraft configuration, thrust, and trajectory data; and the processor is further structured to determine the Current Touchdown Point position and elevation as a function of the aircraft configuration, thrust, and trajectory data. 22. The apparatus of claim 19, further comprising a source of current atmospheric condition data; wherein the processor is further coupled to receive the current atmospheric condition data; and the processor is further structured to determine the Current Touchdown Point position and elevation as a function of the current atmospheric condition data. 23. The apparatus of claim 19 wherein: the processor is further structured to determine a direction of the runway and a current glide path of the host aircraft; the signal generator operated by the processor is further structured to retrieve the current glide path and runway direction information, compare the current glide path and runway direction information, and output a signal representative of a degree of coincidence of the current glide path and runway direction; and the cockpit indicator structured to receive the signal output by the signal generator and responsively output an indication of the degree of coincidence of the current glide path and runway direction. 2