Patent ID: 9548913
Date: 2017-01-17
CPC Classifications: H04B,H04L,H04Q

Claim:
1. A communication system comprising: a transmission unit that repeatedly transmits a transmission signal for communication to a communication line, a first terminal apparatus that communicates with at least the transmission unit by the transmission signal that conforms to a first protocol; and a second terminal apparatus that communicates with at least the transmission unit by a superimposition signal that is superimposed on the transmission signal and conforms to a second protocol different from the first protocol, the transmission unit, the first terminal apparatus and the second terminal apparatus being connected to the communication line, and the first terminal apparatus and the second terminal apparatus being separately addressable relative to the transmission unit, wherein the transmission signal is a time-division signal that is divided, frame by frame, into a plurality of regions in a time axis direction, including: a transmission segment for transmitting data to the first terminal apparatus; and a reply segment that is a time slot for receiving response data from the first terminal apparatus, and wherein the transmission unit includes: a superimposition requesting unit configured to transmit superimposition requesting data to the second terminal apparatus; and a superimposition communication unit configured to receive superimposition response data that the second terminal apparatus transmits in the reply segment with the superimposition signal in response to the superimposition requesting data.