Abstract: A digital transmission apparatus, which accommodates a plurality of terminals for exchanging asynchronous frames each including a MAC address, and is used for transmitting the asynchronous frames by putting each of the asynchronous frames in a synchronous frame, includes an address table for storing an address of a group including the digital transmission apparatus, a header-creating unit for creating a header including a communication-destination transmission-apparatus identification including an address of a group including the digital transmission apparatus and a header-adding unit for creating a first frame by adding the header to data of an asynchronous frame received from any one of the terminals.

Abstract: A remote sensor (100) is remotely placed within a vessel containing a fluid in order to sense a pressure generated by the fluid. The sensor includes an antenna (10) for capturing an externally-generated interrogation signal and for transmitting a response signal, a response circuit (20, 30) coupled to the antenna (10) for receiving the interrogation signal and for generating the response signal, and a sensor element (40) coupled to the response circuit. One or more electrical characteristics of the response circuit (20, 30) change in relation to the sensed pressure, thereby determining measurable characteristics of the response signal. Importantly, the response circuit (20, 30) operates to delay the transmission of the response signal to a time separated from and following transmission of artifacts of the interrogation signal.