China, though, has radar installations arrayed on mountains with overlapping coverage and the ability to look deep into neighboring countries, according to Mark Stokes, a former United States military attaché in China who is now the executive director of a defense research group, the Project 2049 Institute in Arlington, Va.
The Chinese are probably “a little bit more on the ball,” Mr. Stokes said.
http://www.nytimes.com/2014/03/19/wo...h.html?hp&_r=0
The Indian and perhaps Nepalese military may have more exact knowledge of where and how low Chinese primary radar reaches -- not that I think they will share that with us.
The Chinese of course want attaches to think that everything will be detected and tracked.
Mind you, taking a Turbo Porter on a smuggling run down a Himalayan gorge looks much more doable than in a T7.
Remember that there's not much point running primaries in a mountainous area without an interceptor force that can get to low level traffic sneaking up a valley.
A mountaintop primary getting an echo from a target below it needs software to separate that echo from the ground behind it.
These concerns stated, the Chinese primaries could be as good as advertised.