I was jogging along the 4th ring road from the airport expressway exit to Chaoyang park and was trying to hold a phone convo at the same time. The call dropped 3 times in 10 minutes. The person I was talking to was in the middle of Jing'an. I told them that it was to be expected as I was in the middle of the capital and they were in the middle of China's largest city, we wouldn't expect to have good connectivity . We both use Unicom.