Faulty inaccessible sewer pipe discovering method - involving use of external pulse basis radar and internal continuous wave frequency modulation radar process

摘要

A movable antenna device is used to transmit and receive a first electromagnetic radiation. This device is moved along the surface of the material in which the pipe is located. From the first antenna device a first electromagnetic radiation is sent and received and penetrates the material and is reflected from the pipe and/or the fluid which it contains. The signal received from the first antenna device with regard to a fault point through the fluid in the pipe penetrates the surrounding material is evaluated. When a possible fault point is discovered, a second movable antenna device is used to transmit and receive a second electromagnetic radiation which at least partly penetrates the walling of the pipe. The second radiation is reflected on the material surrounding the pipe and is received by the second antenna device. The received signal is evaluated using a vehicle-mounted computer in relation to a faulty walling and the determn. of the exact position of the fault point is effected. USE - To determine position of fault in underground canalisation pipe.