LTE / LTE-Advanced

LTE-Advanced Technology Overview

Long Term Evolution (LTE) was defined to ensure the competitiveness of UMTS for the next decade and to provide a high-data-rate, low-latency and packet-optimized system. LTE, also known as Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN), is specified in 3GPP Release 8. LTE can be operated in either frequency division duplex (FDD) or time division duplex (TDD) mode, also referred to as LTE FDD and TD-LTE. Besides peak data rates of more than 150 Mbit/s (2x2 MIMO) in the downlink and 50 Mbit/s in the uplink, a significant increase in spectrum efficiency and capacity as well as a significant latency reduction are implemented.

Commercialization of the LTE technology started at the end of 2009. By the end of 2010, about 20 LTE FDD networks were commercially available, and first TD-LTE networks will follow shortly.

LTE-Advanced. In order to make LTE a true 4th generation mobile communications technology, it is being enhanced to meet the IMT-Advanced requirements. The necessary enhancements are specified in 3GPP Release 10 and later and are known as LTE-Advanced. IMT-conformant systems will be candidates for future spectrum bands that are still to be identified, which is another major reason for aligning LTE-Advanced with the call for IMT-Advanced technologies. This ensures that today’s deployed LTE mobile networks provide an evolutionary path towards many years of commercial operation. LTE-Advanced will further increase peak data rates towards 1 Gbit/s in the downlink and 500 Mbit/s in the uplink.

The feature candidates for LTE-Advanced are:

Carrier aggregation
MIMO extension (DL: 8x8; UL: 4x4)
Clustered SC-FDMA (UL)
Simultaneous data and control information (PUSCH and PUCCH) transmission
Improving cell edge performance (enhanced inter-cell interference cancellation, relaying)

Deployment Scenario

E-UTRAN can be deployed as a standalone network, but integration with existing WCDMA/HSPA, GSM/GPRS/EDGE and CDMA2000®1xEV-DO networks will become a typical deployment scenario. Thus, mobility between the different technologies needs to be supported, and handover procedures have been specified accordingly. LTE and LTE-Advanced focus on the packet-switched domain and will benefit all applications with high data rates and low latency requirements.

Rohde & Schwarz Test Solutions

Rohde & Schwarz was the first supplier on the market with test solutions for LTE. Flexible and easy-to-use solutions for LTE signal generation and analysis enable the testing of RF and physical layer implementations. A special highlight are the unique test solutions for MIMO. The versatile R&S®CMW500 wideband radio communication tester addresses all stages of wireless device testing, from early R&D up to conformance testing and production. Scalable RF test systems such as the R&S®TS8980 LTE RF test system and the powerful R&S®TSMW universal radio network analyzer complete the Rohde & Schwarz test and measurement portfolio for LTE. Initial LTE-Advanced test functions are available on signal generators and analyzers. Future implementations will reflect the latest 3GPP enhancements.

Key Parameters

	LTE / LTE-Advanced
Frequency range
Frequency range	Show / Hide E-UTRA/FDD Bands 1) UL: 1920 MHz - 1980 MHz DL: 2110 MHz - 2170 MHz 2) UL: 1850 MHz - 1910 MHz DL: 1930 MHz - 1990 MHz 3) UL: 1710 MHz - 1785 MHz DL: 1805 MHz - 1880 MHz 4) UL: 1710 MHz - 1755 MHz DL: 2110 MHz - 2155 MHz 5) UL: 824 MHz - 849 MHz DL: 869 MHz - 894 MHz 6) UL: 830 MHz - 840 MHz DL: 875 MHz - 885 MHz 7) UL: 2500 MHz - 2570 MHz DL: 2620 MHz - 2690 MHz 8) UL: 880 MHz - 915 MHz DL: 925 MHz - 960 MHz 9) UL: 1749.9 MHz - 1784.9 MHz DL: 1844.9 MHz - 1879.9 MHz 10) UL: 1710 MHz - 1770 MHz DL: 2110 MHz - 2170 MHz 11) UL: 1427.9 MHz - 1447.9 MHz DL: 1475.9 MHz - 1495.9 MHz 12) UL: 699 MHz - 716 MHz DL: 729 MHz - 746 MHz 13) UL: 777 MHz - 787 MHz DL: 746 MHz - 756 MHz 14) UL: 788 MHz - 798 MHz DL: 758 MHz - 768 MHz 15) UL: 1900 MHz - 1920 MHz DL: 2600 MHz - 2620 MHz ¹⁾ 16) UL: 2010 MHz - 2025 MHz DL: 2585 MHz - 2600 MHz ¹⁾ 17) UL: 704 MHz - 716 MHz DL: 734 MHz - 746 MHz 18) UL: 815 MHz - 830 MHz DL: 860 MHz - 875 MHz 19) UL: 830 MHz - 845 MHz DL: 875 MHz - 890 MHz 20) UL: 832 MHz - 862 MHz DL: 791 MHz - 821 MHz 21) UL: 1447.9 MHz - 1462.9 MHz DL: 1495.9 MHz - 1510.9 MHz 22) UL: 3410 MHz - 3490 MHz DL: 3510 MHz - 3590 MHz ²⁾ 24) UL: 1625.5 MHz - 1660.5 MHz DL: 1525 MHz - 1559 MHz E-UTRA/TDD Bands 33) 1900 MHz - 1920 MHz 34) 2010 MHz - 2025 MHz 35) 1850 MHz - 1910 MHz 36) 1930 MHz - 1990 MHz 37) 1910 MHz - 1930 MHz 38) 2570 MHz - 2620 MHz 39) 1880 MHz - 1920 MHz 40) 2300 MHz - 2400 MHz 41) 2496 MHz - 2690 MHz 42) 3400 MHz - 3600 MHz 43) 3600 MHz - 3800 MHz 1) Europe only (ETSI EN 301 908-2) 2) planned
Modulation	DL: QPSK, 16QAM, 64QAM UL: QPSK, 16QAM, 64QAM (optional)
Duplex (uplink/downlink)	FDD / TDD
	LTE	LTE-Advanced
Multiple access	DL: OFDMA UL: Localized SC-FDMA	DL: OFDMA UL: Localized SC-FDMA, Clustered SC-FDMA
Channel bandwidth	scalable to 20 MHz	scalable to 20 MHz, with band aggregation up to 100 MHz
MIMO mode	DL: 2x2, 4x2 UL: 1x2, 1x4	DL: 2x2, 4x2, 4x4, 8x4 UL: 1x2, 2x2, 2x4, 4x4, 4x8
Peak data rate requirements	DL: 300 Mbit/s (20 MHz 4x4 MIMO) UL: 75 Mbit/s (20 MHz)	DL: 1 Gbit/s UL: 500 Mbit/s

Standardization

LTE is being specified in 3GPP (3rd Generation Partnership Project). Work on LTE started in December 2004 with a feasibility study that was finalized in 3GPP Release 7. LTE specifications for the FDD and TDD modes form part of 3GPP Release 8. 3GPP Release 9 will bring further enhancements to LTE. Furthermore, the study item on LTE-Advanced as the next evolution stage was started in 2009 to investigate how LTE can become a true 4G system. In September 2009 the 3GPP partners made a formal submission to the ITU proposing that LTE Release 10 and beyond should be evaluated as a candidate for IMT-Advanced. The candidate was accepted on October 20, 2010.

The following link provides access to 3GPP specifications: http://www.3gpp.org