Long-Term Evolution Time-Division Duplex

Long-Term Evolution Time-Division Duplex (LTE-TDD), also referred to as Time-division Long-Term Evolution (TD-LTE), is a 4G telecommunications technology and standard co-developed by an international coalition of companies, including China Mobile, Datang Telecom, Huawei, ZTE,Nokia Solutions and Networks, Qualcomm, Samsung, and ST-Ericsson. It is one of two variants of the Long Term Evolution (LTE) technology standard, the other being Frequency-Division Long-Term Evolution (LTE-FDD).

Overview of technology

Time-Division Duplex LTE, abbreviated as TD-LTE, TDD LTE, or LTE-TDD is one of the two mobile data transmission technologies that fall under the international standard of LTE, the other being Frequency-Division Duplex (LTE-FDD). LTE-TDD was developed specifically with idea of migration to 4G from the third generation 3G TD-SCDMA networks in mind.

There are two major differences between LTE-TDD and LTE-FDD: how data is uploaded and downloaded, and what frequency spectra the networks are deployed in. While LTE-FDD uses paired frequencies to upload and download data, LTE-TDD uses a single frequency, alternating between uploading and downloading data through time. The ratio between uploads and downloads on a LTE-TDD network can be changed dynamically, depending on whether more data needs to be sent or received. LTE-TDD and LTE-FDD also operate on different frequency bands, with LTE-TDD working better at higher frequencies, and LTE-FDD working better at lower frequencies. Frequencies used for LTE-TDD range from 1850 MHz to 3800 MHz, with several different bands being used. The LTE-TDD spectrum is generally cheaper to access, and has less traffic. Further, the bands for LTE-TDD overlap with those used for WiMAX, which can easily be upgraded to support LTE-TDD.

LTE

LTE may refer to:

Science and technology

Education

Organizations and companies

Miscellaneous

Rohde & Schwarz

Rohde & Schwarz GmbH & Co KG (/ˈroʊdə ənd ˈʃwɔːrts/; German pronunciation: [ˈʁoːdə ʊnt ˈʃvaʁts]) is an international electronics group specialized in the fields of electronic test equipment, broadcast & media, cybersecurity, radiomonitoring and radiolocation, and radiocommunication. The company provides products for the wireless communications, broadcast & media, cybersecurity and electronics industry, aerospace and defense, homeland security and critical infrastructures.

The group has been developing, producing and marketing electronic products for the capital goods sector since 1933. In addition to the Munich headquarters, there are regional headquarters in the US (Columbia, Maryland) and in Asia (Singapore). Almost 5500 of the company's employees work in Germany, including the around 2000 employees at the Munich headquarters.

Worldwide, the company has a total of around 9900 employees in over 70 countries. Rohde & Schwarz is family-owned and self-financing. Exports account for approx. 90 percent of revenues. The company invests around 16 percent of its annual net revenue in research and development.

FDD

FDD may refer to:

Science and technology

Other uses

Redmi

RedMi is a smartphone brand manufactured by Xiaomi that was first announced in July 2013. Redmi phones use the Android operating system. The phones were previously branded under the name HongMi. Models include the Redmi 1, Redmi 1S and Redmi Note. Redmi phones have been marketed in China (including Hong Kong), Taiwan, Singapore and India. The most significant difference from traditional Xiaomi smartphones is that it uses less-expensive components and is more consumer-oriented. However, the Redmi 1S and Redmi Note (4G edition) both have a mid-range Snapdragon 400 series chipset. In August 2014, The Wall Street Journal reported that in the second-quarter of the 2014 fiscal year, Xiaomi smartphone shipment rankings in China with a market share of 14%. Redmi sales were attributed as a contributing factor toward this gain in shipment rankings.

2013

The RedMi phone released in 2013 was first announced on the Xiaomi's website, with consumer sales beginning on July 12, 2013. When first launched, supply was limited to units for China and 10,000 units for Hong Kong.