To sent a value of B2-byte sent from a transmitter side transmission terminal station to a receiver side terminal station even when a pointer is revised in the radio repeater corresponding to the Synchronous Digital Hierarchy SDH.

A B2 extract means 2a of the radio repeater 2 extracts B2 byte information. On the other hand, a B2 re-arithmetic means 2b revises a painter of received transmission information and conducts again B2 parity arithmetic operation. Then an adder means 2c adds data extracted by the B2 extract means 2a to data obtained by the B2 re-arithmetic means 2b for each bit. A transmission means 2d sends a scum obtained by an adder means 2c to a succeeding radio repeater 3. The radio repeater 3 recognizes occurrence of an error in B2 parity arithmetic object data corresponding to bits of a value '1' based on the sum sent from the transmission means.