Police in Beijing uses ultrasound to guide police dogs from distance

Chinese police in Beijing are using an ultrasonic remote control method to command the police dogs from a distance in a bid to catch the suspects by surprise, state-run media reported Monday.

Inaudible to humans, the ultrasonic signals are heard by dogs, which have a wider range of hearing, Global Times reported.

"We hope to silently guide our police dogs at a distance without disturbing criminal suspects, especially in some specific tasks," Liu Xiaoxiao, vice-captain of the city police corps, told the daily.

The police have filed a patent for the ultrasonic remote control method being used on the dogs.

Dogs accustomed to one officer's voice may fail to follow orders from a different officer. Ultrasonic uses an identical passphrase coded into a radio signal, enabling different police to guide their dogs' behaviour, Liu said.

The experiment started out in 2016, he said.

Initially the police were using high-frequency dog whistles to train their canines. In the process, they discovered dogs also responded to radio signals.

The method is still new to dogs, with only one or two able to respond so far.

"It proved to be a feasible way, but we are still in development," Liu said.

This method was on display at a Beijing Municipal Public Security Bureau demonstration organized by the police dog base on Saturday.

The trained mutts impressed audiences with their skills and intelligence at searching for explosives, sniffing for drugs on human bodies, searching for gasoline and moving objects, the report said.