A device for deflecting acoustic waves for an object in a liquid environment includes an electrical power source located in the object. A heating grid is positioned about the object in the liquid environment, and a cooling grid is also positioned about the object in the liquid environment such that the heating grid is located between the object and the cooling grid. A least one Peltier device is joined to the electrical power source and the cooling grid for providing cooling. Resistance heating or the Peltier device can be joined to the heating grid for providing heating.

A device for deflecting acoustic waves for an object in a liquid environment includes an electrical power source located in the object. A heating grid is positioned about the object in the liquid environment, and a cooling grid is also positioned about the object in the liquid environment such that the heating grid is located between the object and the cooling grid. A least one Peltier device is joined to the electrical power source and the cooling grid for providing cooling. Resistance heating or the Peltier device can be joined to the heating grid for providing heating.

An active sensing system includes an agent and at least one sensor operatively associated with the agent. The at least one sensor includes one or more emitters configured and disposed to establish a sensing zone. A conflict identification module is configured and disposed to identify one or more sensor conflict regions, and an active sensor controller is operatively connected to the at least one sensor and the conflict identification module. The active sensor controller is configured and disposed to form an adjustment zone within the sensing zone to accommodate the one or more sensor conflict regions.

An object detection apparatus includes a transmission signal generator, a correlation signal generator, and a signal determiner. The transmission signal generator can generate a plurality of types of transmission signals changing frequencies thereof over time, and outputs one of the plurality of types of transmission signals to a transmitter transmitting a probe wave having a frequency thereof modulated based on a frequency change mode of the transmission signal. The correlation signal generator generates a correlation signal indicating a correlation between a reference signal and a reception signal. A plurality of correlation signal generators are provided in correspondence with the plurality of types of transmission signals. The signal determiner performs a signal determination of determining, based on the correlation signal, whether a received wave has a frequency change mode corresponding to a frequency modulation mode of the probe wave, and performs the signal determination by comparing a plurality of correlation signals.