The Global Mobile Suppliers Association (GSA) has confirmed a rising number of operator commitments to long term evolution- time division duplex (LTE-TDD) TDD (network deployments, new commercial service launches, increasing variety of user devices, especially smartphones, and accelerating subscriber growth. So far, 39 operators, which are around one in eight LTE operators, have commercially launched LTE TDD (TD-LTE) systems in 26 countries. Another 48 operators are currently deploying or planning networks and a number of operators are undertaking technology trials and studies. GSA has therefore calculated that almost 120 operators globally are investing in LTE TDD.

Within the current total of 39 commercially launched LTE TDD networks, 13 operators have launched converged systems, i.e. using both TDD and frequency division duplex (FDD) mode in the networks. GSA further confirmed that converging of systems is a growing industry trend. For instance, some Indian operators have deployed converged networks using LTE FDD 1800 MHz and TDD 2.3 GHz spectrum.

The devices ecosystem for the TDD mode is mature and has expanded rapidly. Within the total of 1,889 LTE user devices that have been introduced to the market, as recently confirmed by GSA, 530 products i.e. 28 per cent of all LTE devices can operate in the LTE TDD mode. There has been an increase of 330 LTE user devices in the last one year. GSA also confirmed that 85 device manufacturers have launched LTE TDD products.

Alan Hadden, President of GSA, said “TDD operators are focusing more on personal mobility and the smartphone is the key segment. Recent progress has been excellent and 184 TDD smartphone products have now been announced, which is 87 per cent more than the total in March 2014. A year ago, 52 per cent of LTE TDD devices were routers (including personal hotspots), while smartphones had only 10 per cent share. Now routers make up 38 per cent of TDD products, and the smartphone category has grown its share to 35 per cent. Band 40 (2.3 GHz) and band 38 (2.6 GHz) have the largest choice of TDD terminals, each band being supported by 68 per cent of all LTE TDD devices. The terminal support for band 39 is 38 per cent, band 41 is 34 per cent, and band 42 is 4.5 per cent. Moreover, 96 per cent of TDD smartphones are multimode, supporting one or more 3G system technologies, as well as LTE TDD. Band 40 (2.3 GHz) is used in most commercially launched LTE networks currently.”

GSA has forecasted that the global TDD share of LTE subscriptions - fuelled by its popularity in China with 14 million LTE TDD subscribers by end June 2014 - will surge from around 5 per cent in first quarter 2014 to over 15 per cent by end 2014.