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Learn how to configure Rohde & Schwarz products to fit your application. Search our database by product, technology, or application to find relevant technical documents.
Search Application Notes & Cards
Learn how to configure Rohde & Schwarz products to fit your application. Search our database by product, technology, or application to find relevant technical documents.
134 Results
Due to its outstanding performance the R&S®SMW200A vector signal generator is ideal for testing MIMO receivers in a vast variety of applications offering maximum usability at minimum form factor. It can generate up to eight antenna signals simultaneously in its digital baseband – all standard-compliant and with antenna-specific coding. In addition, it can simulate the complete MIMO transmission channel with up to 32 fading channels, sufficient to emulate higher-order MIMO configurations such as 3x3, 4x4, and 8x4.This application note explains how to use the SMW for testing higher order MIMO systems by presenting different key applications.
24-Feb-2016 | AN-No. 1GP97
The Doherty Amplifier continues to be rolled out in an increasing number of TxFE (Transmit Frontend) applications, as the quasi-linear amplifier architecture of choice.The advent of 5G, with its inevitable microwave or millimeter wave air interface, increase the design challenges associated with its construction; not least of all because of the potential for increased dispersion in the constituent amplifiers and combiners.This application note describes a measurement-based development methodology by which the Doherty Amplifier may be enhanced, increasing performance and/or performance bandwidth. This methodology is supported with a working example.The methodology may also be extended to balanced, spatially combined and anti-phase (so called "pushpull" or "differential") amplifiers, the latter often itself nested in Doherty configurations.The R&S®Quickstep sequencing software may be downloaded from:
26-Sep-2016 | AN-No. 1MA279
Digital pre-distortion (DPD) is a common method to linearize the output signal of a power amplifier (PA), which is being operated in its non-linear operating range.Most PAs operate in their non-linear range for efficiency reasons. The drawback of higher efficiency is the non-linear operating range. In order to maintain signal quality, many transmitters employ DPD. Implementing real-time DPD in a transmitter is a challenging task and often ends in PA models, which are specific to the signal transmitted.Even though these complex models are required for transmitter development, they are not needed during PA verification and development.This article describes an approach to generate a pre-distorted signal based on a hard-clipper. The resulting waveform pushes the output of the DUT as close to the hard-clipper as possible.Due to the waveform approach, the algorithm compensates all memory effects.
13-Sep-2017 | AN-No. 1EF99
Receiver diversity improves reception quality by using multiple antennas with a preferably low correlation factor between each receive path. The result is a much more robust reception, since a deep fade will not affect all received signals at the same time.However, the complex geometry and positioning constraints for antennas of the receiving devices can introduce an unwanted correlation between channels. The popular diversity test setup consisting of several independent transmitters does not serve the needs of a realistic simulation, because radio channel correlation is not simulated.This application note explains a compact and versatile MIMO test solution for any common broadcast standard with real time fading including the simulation of channel correlation for a 1x4 MIMO system.The test setup allows very precisely specified individual multipath profiles.
11-Oct-2017 | AN-No. 1GP114
With all these new flexibilities introduced with 5G, the radio access has become more complex to understand and analyze. More network interfaces and RAN configuration parameters have to be managed and the RAN and in particular the connection control, mobility and measurement reporting are decisive for the network performance. It will be vital for the system experts and radio engineers to gain knowledge and evolve their methods and tools to facilitate the work to optimize and troubleshoot 5G and 4G RAN performance. Thus, tools are needed that allow for easier understanding of the message flows in the radio protocols. The R&S®ROMES4 KPIs and Smart Events will help doing the work much easier and quicker. They are defined for a key set of LTE, EN-DC and NR RRC connection control and mobility procedures where the performance is crucial to achieve high quality network performance. Trouble shooting problematic cases and optimization of RAN protocols are key drivers to improve the mobile network performance with R&S®ROMES4.
28-Jun-2022 | AN-No. 8NT06
This application note provides an introduction to the DDR memory technology and explains common challenges, related to the specific nature of DDR data, command / address and control buses and describes the typical measurements to verify and debug DDR system designs.The paper explains the recommended test points and the connection of oscilloscope probes as well as the compensation of effects from DDR interposers via deembedding. The document describes efficient Signal Integrity verification with eye diagram measurements, advanced triggering and TDR/TDT functionality. Given the high number of signal lines and the dynamic bus termination, SSN (simultaneous switching noise) has a significant effect in DDR memory designs and Signal Integrity as well as Power Integrity is highly pattern dependent. We introduce techniques to achieve high acquisition rates and help to efficiently detect worst case scenarios, affecting the performance of the overall memory design. The document also includes a close look on Power Integrity.Providing best practice examples in the design verification and debugging process, the document addresses all system designers and test engineers, working on DDR memory designs.
30-Oct-2020 | AN-No. GFM340
3GPP TS36.141 defines conformance tests for EUTRA base stations (eNodeB). Release 14 added several tests, especially for enhanced License Assisted Access (eLAA).This application note describes how all required receiver (Rx) tests (TS36.141 Chapter 7) can be performed quickly and easily by using vector signal generators from Rohde & Schwarz. A few tests additionally require spectrum analyzers from Rohde & Schwarz.Examples illustrate the manual operation. A free software program enables and demonstrates remote operation.The LTE base station transmitter (Tx) tests (TS36.141 Chapter 6) are described in Application Note 1MA154.The LTE base station performance (Px) tests (TS36.141 Chapter 8) are described in Application Note 1MA162.
11-May-2016 | AN-No. 1MA195
Receiver diversity improves reception quality by using multiple antennas with a preferably low correlation factor between each other. This results in a more robust handling of multipath signals, since a deep fade will then not affect all received signals at the same time. However, the compact dimensions of handheld devices can introduce unwanted correlation due to their dense antenna spacing. In this case, the popular diversity test setup consisting of several independent transmitters will no longer serve the needs of a realistic simulation, since correlation effects have to be taken into account here. A clever solution is to operate the R&S®SFU in split-fading mode in combination with a second transmitter. This can be another R&S®SFU, the R&S®SFE, the R&S®SFE100 or the R&S®SMU200A. In this way, two diversity signals of adjustable correlation for any common broadcast standard are coded in realtime, while their individual multipath profile is precisely specified by the extensive features of the R&S®SFU fader module.
19-Oct-2012 | AN-No. 7BM76
The application note guides developers and manufactures of Sigfox Devices to perform the required and recommended measurements with test solutions from Rohde & Schwarz. The note will help bring ultranarrowband IoT devices and applications using Sigfox technology to the market as fast as possible and help ensure the desired quality and performance.For R&D, Pre-certification and QA, all currently defined Uplink- and Downlink- measurements are shown using the compact R&S®FPL1000 Spectrum Analyzer and R&S®SMBV100A Vector Signal Generator.For Production, use of the R&S®CMW100A Communications Manufacturing Test Set is shown for the most essential Uplink RF tests on Sigfox Devices.Python scripts for giving example SCPI commands demonstrate how measurements shown in manual use can easily be automated.
15-Nov-2017 | AN-No. 1MA294
More and more everyday items such as household appliances, vehicles, lights, etc. are now connected to the Internet, forming what is known as the "Internet of Things". Even clothing with sewn-in sensors to measure vital functions can now connect to the Internet and transmit data to cloud services. These different things use a variety of wireless technology standards to establish a connection. Due to its popularity, one of the most important standards is Bluetooth (or Bluetooth Low Energy). Before a new product with Bluetooth functionality can be launched, the qualification process defined by the Bluetooth SIG must be successfully completed. To save time and money, performance tests need to be performed in the development stage. This application note describes how to use the R&S CMW platform to perform the measurements defined in Bluetooth test specification version 5. As an alternative solution, we also cover how to perform almost all of the measurements with a spectrum analyzer and signal generator.The Bluetooth® word mark and logos are registered trademarks owned by Bluetooth SIG, Inc. and any use of such marks by Rohde & Schwarz is under license.
19-Jun-2017 | AN-No. 1MA282
For several years, vehicle manufacturers and government agencies have sought ways to increase road safety, manage traffic efficiently and, in the future, make driving more comfortable, convenient and safe. Vehicle-to-everything (V2X) is a new generation of information and communication technology that connects vehicles to everything and can support these objectives. V2X is designed to offer low-latency vehicle-to-vehicle (V2V), vehicle-to-roadside infrastructure (V2I) and vehicle-to-pedestrian (V2P) communications to add a new dimension to future driver assistance systems.Cellular V2X (C-V2X) is defined as the communications standard by 3GPP in Release 14 and uses LTE technology as the physical interface for communications.The LTE C-V2X Scanner provides customers an opportunity to verify, test, and optimize ITS traffic systems that are being deployed or are already established. The scanner accomplishes this by passively listening to PC (5.9GHz) messages that are being broadcast from RSU (roadside units), vehicles or any other C-V2X enabled device. Traditional scanner measurements regarding RF signal power and quality such as RSRP, RS-CINR and RSSI, are provided for each physical channel (PSCCH and PSSCH) as well as decoded ITS message content for all three regions (North America, EU, China).
21-Oct-2022 | AN-No. 8NT07
A turnkey 5G Field-to-Lab solution based on R&S®CMX500
5G New Radio (NR) is the fifth-generation radio interface and radio access technology (RAT) which was officially published by 3GPP in release 15. With the 5G technology, it enters a new era to meet the ever-increasing demands of mobile communications not only in the conventional cellular communication world, but also in the vertical industries.Since the commercialization of 5G NR, worldwide 162 networks have been deployed as per the report of GSA. On the path to the 5G NR network commercialization and service launch, field test is one of the essential user centric processes that User Equipment (UE) vendors should go through. Sophisticated features and versatile deployment options have to be thoroughly checked to ensure the reaching of certain confidence level before the official launch.However, field test is often linked with some challenges, such as► High costs due to the extensive drive tests► Time tedious analysis of a drive test that lowers the efficiency► Lack of test repeatability that makes the regressing tests impossibleWhat if providing an alternative solution in a laboratory environment to cope with all above mentioned challenges during the field test? R&S® as a world-wide well established test measurement equipment manufacturer and solution provider developed a 5G field-to-lab (F2L) turn-key solution, R&S®CM360°. It features► the simulation of the network with the real network configurations to avoid the cost intensive drive test by utilizing mobile radio tester R&S®CMX500► intuitive tools to visualize, drill down the problems and therefore enhance the debugging efficiency based on R&S®SmartAnlytics► the specialized key performance indicator (KPI) tests configured through real network data offered on R&S®CMX500 that guarantee the test reliability and repeatabilityThis application note aims to demonstrate the status of quo R&S®CM360° F2L solution.
16-Jul-2021 | AN-No. 1SL369
Propagation measurements are indispensable in the planning of digital, cellular mobile radio net-works. To find the optimum sites for the base stations, a mobile test transmitter system simulating the base station is operated from a number of possible locations. The test receiver system is accommodated in a vehicle, which is driven along a test route to perform measurements. The parameters measured, such as level, bit error rate or channel impulse response, provide information on the coverage within the cell. The main problem is to minimize interference caused by multipath propagation in the reception area. The SME offered by Rohde & Schwarz is a universal test generator that can be used as the core of a test transmitter system. The SME generates the GMSK-modulated signals required for GSM propagation measurements in line with the rele-vant standards. Thanks to its low weight of 17 kg it can be carried even to remote sites. Fitted with the new optional DM Memory Extension (SME-B12, in the following referred to as XMEM), the SME is able to store data sequences of up to 8 Mbit which are long enough for receiver measurements with test mobile stations. A suitable test receiver system is for instance a test mobile station for measuring level and bit error rate and the Impulse Response Analyzer PCS from Rohde & Schwarz for measuring the channel impulse response. The present Application Note describes how the XMEM can be loaded with suitable data (test sequence) by the GSM Radiocommunication Test Set CRTP from Rohde & Schwarz and how the SME has to be adjusted for GMSK modulation of these data. First, however, an overview is given of all functions of the XMEM and their operation supplementary to the Operating Manual. Finally, it is explained how the XMEM data can be transferred between PC and SME via the IEEE-488 or RS-232 interface.
01-Jul-1999 | AN-No. 1GPAN14
A step by step HOW TO guide to perform manual and automated wireless coexistence testing
At the end of the year 2020, there were over 20 Billion internet of things (IoT) products in the world operating using the licensed and unlicensed frequency bands. This growth trend is projected to keep steady over the coming years as more and more people adopt to a smarter and more connected lifestyle. This will result in a much busier and challenging RF environment than the one we have today. In order to understand the complexity of the RF spectrum, a white paper was published in 2021 from Rohde & Schwarz, which featured RF spectrum activity at multiple locations observed at different times of the day. The locations were selected based on population densities and the amount of known RF transmitters & their frequencies at those locations. It was also concluded that the ISM bands on average have higher channel utilization since most IoT devices take advantage of the unlicensed spectrum. The paper recommended, that while performing wireless coexistence testing, the test conditions should reflect the operational RF environment that the device is intended to operate in. Otherwise, the characterization of RF performance would only reflect ideal case which doesn’t exist in real world operation. Since it is not always possible to test all devices in the real world, relevant test methodologies need to be setup to replicate the real world as much as possible.This will help us get a better understanding of how the receiver of the RF device will behave under different RF conditions. It is also recommended to perform measurements in order to understand the behavior of the device in the future when the spectrum will get even more challenging. Therefore, a through characterization of the capability of the RF receiver to handle in-band and out-of-band interference signals in also of interest.In terms of regulatory compliance requirements for ensuring wireless coexistence performance, the ANSI C63.27 is currently the only published test standard that provides guidance on how to perform coexistence testing on devices. The test complexity is based up on risk imposed on the user’s health in the event of a failure caused by an or a plurality of interference signal. The standard also gives device manufacturers guidance regarding test setups, measurement environments, interference signal types and strategy, performance quality measurement parameters for physical layer using key performance indicator (KPI) and application layer parameters for end-to-end functional wireless performance (FWP).In this application note, the guidance provided by the ANSI C63.27-2021 version regarding test setup, measurement parameter and interference signal have been followed. It will give the reader a clear idea on how to configure standardized test instruments from R&S in order to generate the wanted signal as well as unintended interference signals and conduct measurement to monitor device performance in terms of PER, ping latency and data throughput.This application note provides step-by-step instruction on how to perform measurements using conducted and radiated methodology. Both manual and automated instrument configuration approach is explained in this document.The automation scripts are written using python scripting language and are available for download with this application note, free of charge. Official required to run the scripts are available on the PYPI database.
10-Nov-2022 | AN-No. 1SL392