The demand for speed is helping LTE market to grow faster. Infonetics says LTE revenue grew 69 percent in 2014 from the previous year. Mobile traffic demand is expected to grow nine times by 2020.
To address the growing demand of mobile Internet, service providers using a concept called FDD/TDD carrier aggregation to increase the downlink capacity, where operators add TDD to the already installed FDD network, FDD/TDD carrier aggregation extends the app coverage of the TDD layer by up to 230 percent.
The first company to support FDD/TDD carrier aggregation is Ericsson, which allows operators just to do some software update to its baseband hardware already operating in the network, Ericsson's Networks Software 15B release enables simultaneous operation of LTE FDD and TDD.
Vodafone is the first operator to implement LTE FDD/TDD carrier aggregation in commercial network by using Ericsson commercial software release 15B supporting FDD/TDD carrier aggregation starting with its network in Portugal.
To tell you on the semiconductor chips supporting this technology QUALCOMM's Snapdragon 810 processor with X10 LTE supports carrier aggregation across LTE TDD and LTE FDD.
Another LTE chip vendor GCT Semiconductor offers an advanced FDD-TDD LTE Category 5/6/7 single chip GDM7243Q with 4X4 MIMO carrier aggregation for LTE.
The Gobi 9x30 from QUALCOMM is cellular modem for automotive based on the 20 nm technology node with support for global carrier aggregation deployments up to 40 MHz in both LTE FDD and TDD modes.
In 2014 itself, Ericsson, SingTel and Qualcomm have made a live demonstration of FDD / TDD Carrier Aggregation using commercial track hardware and software. The demonstration achieved 260 Mbps downlink speeds.
"For operators using TDD bands, the TDD uplink coverage can be a constraint. By combining TDD and FDD spectrum through Carrier Aggregation, low band FDD can deliver good uplink coverage while the TDD band can be leveraged for higher downlink capacity. LTE FDD / TDD Carrier Aggregation enables spectrum from both LTE FDD and LTE TDD to be combined to deliver higher peak data speeds and improve app coverage across the network. It increases the effective TDD coverage area by up to 70%, reducing the cost of providing TDD coverage. It also ensures efficient utilization of spectrum, increasing both the combined FDD / TDD coverage area and capacity of the network", explains Ericsson.