Major Chinese telecom equipment maker ZTE Wednesday reported an almost 30 percent rise in net profits in the first half of the year due to improved sales and margins.

In a filing to the Shenzhen Stock Exchange, ZTE said its net profits rose 29.9 percent year on year to 2.29 billion yuan (339 million U.S. dollars) in the six months ending June.

Sales revenue jumped 13.1 percent year on year to 54 billion yuan during that period, it said.

The Shenzhen-based company said its sales and margins rose as domestic telecom operators continued to invest in 4G telecommunication systems. Meanwhile, as it expanded further into overseas markets, its mobile phones also reported higher sales and margins.