Microwave Journal

Generating and analyzing LTE signals for the first time with R&S SMx-K55 and R&S FSQ-K100

April 17, 2007
Munich, 17 April 2007 — Although the first mobile radio networks were upgraded to high speed packet access (HSPA) only a short time ago, the next advance in UMTS – UMTS long-term evolution (LTE) – is already around the corner. Rohde & Schwarz also supports the enhancement of the standard with its T&M equipment in this case. The company has already added the new technology to its product portfolio. The R&S SMx-K55 option turns the R&S SMU200A, R&S SMJ100A, and R&S SMATE200A into the world's first generators for LTE signals. When equipped with the R&S FSQ-K100 option, the high-end R&S FSQ spectrum analyzer also becomes a pioneer in the field of LTE. Rohde & Schwarz has already presented both solutions at trade fairs, and now they are available for purchase. With LTE, the goal is to achieve data rates of up to 100 Mbit/s in the downlink and up to 50 Mbit/s in the uplink. Moreover, LTE provides significant improvements with respect to access times, data throughput, and spectral efficiency, thus ensuring, above all, the long-term competitiveness of UMTS. As with WiMAX, data transfer from the base station to the mobile phone is based on orthogonal frequency division multiple access (OFDMA). In the uplink, the single carrier frequency division multiple access (SC-FDMA) transmission method is used. The 3GPP LTE standard is specified in 3GPP Release 8 and is scheduled to be launched in 2009. Equipped with the R&S SMx-K55 option, the R&S SMU200A, R&S SMJ100A, and R&S SMATE200A signal generators generate high-quality downlink signals for performing tests on base station components as well as on mobile phone components and receivers. Since the option runs directly on the instruments, no external software is required. The R&S SMx-K55 option supports the OFDMA transmission method, channel bandwidths up to 20 MHz, as well as the QPSK, 16QAM, and 64QAM modulation modes, plus it offers predefined scenarios. Moreover, it is also possible to flexibly set the parameters of reference symbols and control and synchronization channels (BCH, SCH) as well as to configure the subframes independently of each other. Modifications to the standard are covered via free updates. For analyzing downlink LTE signals, the R&S FSQ vector signal analyzer and high-end spectrum analyzer can be equipped with the R&S FSQ-K100 option, which is a flexible PC software application for the development of base stations. This option also makes it possible to quickly respond to modifications to the standard. The R&S FSQ-K100 option analyzes LTE signals in the spectral, time, and modulation domains with all channel bandwidths specified in the standard. For measuring signals in the baseband – whether balanced or unbalanced – the optional baseband inputs of the R&S FSQ are available. The two options are compatible with one another and can therefore be used together. Their high flexibility accommodates the fact that the specifications are not yet fully defined in the standard. The uplink will be available for both solutions in the near future – as a free-of-charge firmware update for the R&S SMx-K55 option, and as the R&S FSQ-K101 option for the R&S FSQ. The R&S SMx-K55 option for generating downlink LTE signals and the R&S FSQ-K100 option for analyzing downlink LTE signals are now available from Rohde & Schwarz.