Different types of frequencies perform a bit differently due to different frequencies behave differently in terms of diffraction, deflection and etc. Regardless which countries, the fundamental physics is the same. The differences are in terms of protocols. When you have large group of people using push-to-talk radio in a area, the channel allocation becomes difficult. It usually ends up people jamming each others, so you hear cross talk all over the place. Through ptt radio, you don't really know who you are really talking to, just try to bring a two-way radio to a big park where many people are using it, then you will know what I mean. Today, the US military has the "caller id" like features for its CNR, I don't think China has that kind of technology. In a theatre, that is battlefield, military is usually prepared, and have those thing planned ahead. Now, disasters like this, nobody plans this ahead. So when you jump into action, who do you want to talk to? I think not every soldiers of PLA has communication equipment, it is in a sense, limited the capacity, but easier to manage. That is why I can't imagine dropping a couple thousand paratroopers will help. There are other problems too, like battery life, and all this kind of things, it is not easy.

Also military and civilian communication are not interoperable, different government agencies also have different equipment, they don't work together either. Since the US is like this, I can't imagine why China is any different. Even satellite phones, at a single area, the capacity is limited, now, suddenly you have reporters, rescuers, military and other government agencies all jam up using sat. phone. Some of them won't get service, and that is by design, there is no way around it. Even the intelsat, and the US move satellites to the region, I don't think it will help that much.