As part of its ambitious military modernisation plan, China has completed a network of air defence radars that is able to provide seamless surveillance to all Chinese territorial airspace.

The network could serve in all-weather conditions, Fang Lei, of the air force headquarters of the Chinese People's Liberation Army, was quoted as saying by the state media.

Air defence radars have been manufactured and deployed by the PLA since 1950 and relied on as the "first line of air defence".

Air defence radar troops are among the high-tech intensive arms of the PLA services, Fang said, adding 85 per cent of the officers held bachelor degrees or above.

More than 60 per cent of air defence radars under human operation were deployed in regions with tough natural environment such as islands and highlands, the officer said.

The detection ability and overall capacity of the PLA's air defence radar network were "very close" to those of developed countries, he said.

With the PLA's modernisation, the air defence radar arm would also provide support to the air force's offensive missions, and to other PLA services, he said.