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.
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.
1104 Results
A programmable data generator such as the combination of SME with option SME-B11 is a novelty with signal generators. To make it easy for the user to get acquainted with the option and to ensure efficient operation, possible applications are described below. The data generator is used for producing binary data as well as control signals for level switching whenever digitally modulated signals are used. For a start we should like to deal in brief with the various settings available for digital modulation. Taking GSM as an example, the programming of data lists will be described next. The description for GSM can be easily applied to other digital networks as well. Next the generation of level bursts and the extension of data generator memory with option SME-B12 are described. The last section deals with special subjects such as FSK using data rates below 400 bits/s and pulse-amplitude modulation. A basic knowledge on digital modulation and TDMA will be sufficient to follow the topics.
01-Jul-1999 | AN-No. 1GPAN08
While Mobile phones are allowed to require approximately 3 time slots for switching from transmission to reception, base stations must be able to transmit and receive at a new frequency in every time slot in the frequency hopping mode. This behaviour must of course be tested and measurements carried out on the base station transmitter and receiver. Since there is no signal generator which is able to settle at different frequencies from one to the next time slot with GSM modulation, a solution to this problem was found by linking two Signal Generators SME in such a way that they alternately provide signals at different frequencies.
01-Jul-1999 | AN-No. 1GPAN28
Communication systems according to IS-136 (NADC) use Time Division Multiplex Access (TDMA) for the communication between base station and mobile stations. There are 6 time slots available. Depending on the amount of data, which have to be transmitted, the system uses full rate channels or half rate channels. A full rate channel means, that the mobile is accessed every 3rd time slot (e.g time slot 1 and 3, time slot 2 and 4 or time slot 3 and 6). With half rate channels the mobile is accessed every 6th time slot. Full rate and half rate channels may be mixed on demand. The base stations transmit continous on their frequency. Depending on the used combination of full rate and half rate channels the base station uses a different sequence of synchronisation words. The mobile stations use bursted transmission with one of the synchronisation words S1 to S6 defined in the standard. Signal Generator SME is excellently suited to generate these signals to test either base station receivers or mobile phone receivers. Together with the modulation data supplied with this application note the SME serves as a signal source for various test and measurement applications in the whole frequency range of IS-136 (NADC).
01-Jul-1999 | AN-No. 1GPAN35
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
The present application note describes the possibilities of the Stream Explorer to be remotely controlled by some peripheral program via OLE. Extensions are also discussed, widening the fields of application of such a Client-Server architecture.
31-Mar-1999 | AN-No. 7BM02
In frequent cases, it appears that the MPEG2 decoder is not located in the control/monitoring room. The present application note describes how to operate a remote control of up to four DVMDs over an ethernet link.
31-Mar-1999 | AN-No. 7BM01
This application note describes the principle of harmonic mixing and the requirements to be met by spectrum analyzers and external mixers.
05-Mar-1999 | AN-No. 1EF43
An FSE Spectrum Analyser equipped with the Vector Signal Analysis option (FSE-B7) can measure oscillator settling time or transmitter attack and release times with high accuracy up to 40 GHz. No additional measurement equipment is needed.
12-Feb-1999 | AN-No. 1MA15
Using option ZVR-B4 (Frequency Converting Measurements), a ZVR Vector Network Analyzer can be used for measurements on frequency converting devices such as mixers and amplifiers. Using the ZVR's ARBITRARY mode, the source and receiver frequency ranges of the ZVR's generator and receiver, plus for two external signal generators, can be defined independently. As a result, mixer and intermodulation products such as conversion loss or sampling mixers, can all be measured. Used together with option ZVR-B6 (Reference Channel Ports), group delay measurements can also be made on frequency converting devices.
19-Jan-1999 | AN-No. 1EZ47
With options ZVR-B4 (mixer measurements), ZVR-B5 (nonlinear measurements) and ZVR-B7 (power calibration) installed, signal generators and power meters can be controlled from ZVR network analyzers via the IEC/IEEE bus. Customary signal generators and power meters are supported by the device firmware. This application note describes how user-specific configuration files can be generated for and adjusted to external equipment of these two categories.
19-Oct-1998 | AN-No. 1EZ46
A test setup is described for easy demonstration of the Bit Error Rate Test (BERT) function of AMIQ/AMIQ-B1. The test setup contains I/Q Modulation Generator AMIQ/AMIQ-B1 controlled by I/Q Simulation Software WinIQSIM, Vector Signal Generator SMIQ and Spectrum/Vector Signal Analyzer FSE/FSE-B7. The FSE with FSE-B7 is used as online FSK demodulator (setting: Analog demodulation, FM Signal, DC coupling, Real Time On) to demodulate the SMIQ RF signal FSK-modulated by PRBS data. The AMIQ is controlled by WinIQSIM software and receives the demodulated AF output signal from the FSE for BER testing.
29-Sep-1998 | AN-No. 1MA16
Embedding and De-Embedding of virtual transformation networks for measuring scattering parameters with a ZVR or ZVC vector network analyzer.
25-Sep-1998 | AN-No. 1EZ45
The measurement accuracy of vector network analyzers can be tested simply, easily and quickly, with a simple DUT which consists of a common tee-junction with one port, terminated with a resistive load Z, and the T-Check program. The four S-parameters from ports 1 and 2 are measured with the vector network analyzer to be checked and then evaluated by means of the T-Check software.
04-Aug-1998 | AN-No. 1EZ43
3-Port Adapter ZVR-B8 is an optional accessory to all Vector Network Analyzers of the ZVR family, namely ZVRL, ZVRE, and ZVR, and extends the two test ports PORT1 and PORT2 to a total of three test ports PORT1, PORT2 and PORT3. The option comprises an electronic single-pole double-throw switch (SPDT) by means of which PORT1 of the analyzer is switched to either PORT1 or PORT3 of 3-Port Adapter. Test port PORT2 of the analyzer is directly connected to PORT2 of the 3-Port Adapter and is not switched over.
04-Aug-1998 | AN-No. 1EZ26
Using the optional three-port or four-port adapter (ZVR-B8 and ZVR-B14), PORT 1 and PORT 2 of the network analyzers of the ZVR family (ZVRL, ZVRE and ZVR) can be expanded to up to four ports. Thus automatic measurements on three- and four-port DUTs can be easily performed without any reconnection of ports being required. With the electronic switches in the adapters, switchover between the various ports is fast to the extent that the known high measurement and display speed of the analyzers of the ZVR family is fully maintained.
04-Aug-1998 | AN-No. 1EZ37
ZVR is a vector network analyzer equipped with selective input channels for determining phase relations. Thus a wide dynamic range can be obtained. For measurements on frequency-converting DUTs (output frequency not identical to input frequency), the generator and receiver frequency ranges can be separately set. For measurements on DUTs using a built-in conversion oscillator, as is the case here, the conversion frequency must be exactly known so that the receiver can be accurately tuned to the respective output frequency. The maximum receiving bandwidth is 26.5 kHz. When a wide dynamic range is required, this bandwidth has to be reduced with the consequence that the requirement for the DUT output frequency and the ZVR receive frequency to be in agreement will be greater.
04-Aug-1998 | AN-No. 1EZ31
Vector Network Analyzers of the ZVR family measure magnitude and phase of complex S-parameters of a device under test (DUT) in the frequency domain. Using an inverse Fourier transform, the results can be transformed to the time domain. The impulse or step response of the DUT is obtained, which gives an especially clear representation of its characteristics. For instance, faults in cables can be directly localized. Moreover, special time domain filters, so-called gates, can be used to suppress unwanted signal components such as multireflections.
04-Aug-1998 | AN-No. 1EZ44
The RSIB interface enables the network analyzers of the ZVR family to be controlled by means of Windows applications via DDE. The interface functions are contained in the DLL RSIB.DLL. The other DLL RSDDE.DLL provides functions for the DDE access to the instrument firmware. These functions are used by RSIB.DLL. The interface of these functions greatly corresponds to that of National Instruments for programming the GPIB. The function names are similar to those of the NI library but preceded by RSDLL. The two DLLs are part of the firmware and are updated with the firmware update kits.
31-Jul-1998 | AN-No. 1EZ33
The option ZVR-B7 allows an enhanced power calibration of the source and of the receiver channels of a ZVR, then being active instead of the standard factory power calibration. Using an external power meter, the power level of input or output wave quantities will be adjusted to a desired value at an arbitrary reference plane.
29-Jul-1998 | AN-No. 1EZ41
Three hardware modifications of the option External Measurements ZVR-B25 enable the bidirectional network analyzers of the ZVR-family to carry out 4-port measurements. For the measurements, the four ports PORT 1, PORT 2, INPUT b1 and INPUT b2 at the front panel of the ZVR(E) are utilized. The fifth connector, ie OUTPUT a1, is not required for this purpose. As detailed below, the necessary modifications of the test set of the analyzer are described for the model ZVR. Of course, the modifications can be done in a similar way for the model ZVRE as well.
28-Jul-1998 | AN-No. 1EZ25
Vector network analyzers are used in high frequency applications to measure the complex scattering parameters of an unknown device-under-test (DUT). In general, the DUT characteristics can be evaluated by using electromagnetic waves. The correlation between the incident, reflected and transmitted wave quantities at the DUT is defined by its scattering matrix S.
28-Jul-1998 | AN-No. 1EZ30
A special requirement for testing GSM components is to measure the electrical characteristics, such as the gain of a power amplifier, of the DUT under pulsed conditions. The test should be similar to real operating conditions for a mobile telephone.
28-Jul-1998 | AN-No. 1EZ42
Using a Vector Network Analyzer from the ZVR family, not only magnitude and phase can be measured, but also group delay and even phase delay. Whereas phase delay measurements produce the highest accuracy for the electrical length of non-dispersive devices under test, such as coaxial cables, group delay measurements also give a detailed insight into the frequency dependent delay characteristics of dispersive devices, such as filters. In addition to the traditional step aperture technique, Vector Network Analyzers from the ZVR family offer a frequency aperture technique, which allows a well defined and constant aperture for group delay measurements also for a nonlinear frequency sweep.
28-Jul-1998 | AN-No. 1EZ35
To quantify uncertainties for network analyzer measurements, the influence of the entire system (network analyzer plus test setup and DUT) has to be taken into account. Usually, the overall uncertainty of the complete measurement setup is determined with the aid of a verification kit, containing highly accurate verification standards. Of course, the verification standards need to have the same connector type as the DUT. If such verification standards are not available, the overall error has to be estimated.
28-Jul-1998 | AN-No. 1EZ29
This Application Note describes the internal transfer of ZVR measurement data in Excel, carried out on the PC option of the ZVR, and the evaluation of the data in Excel tables. To start the data transfers, macros are implemented under Excel.
28-Jul-1998 | AN-No. 1EZ39
This Application Note describes two programs for calculating conversions: 1.: The Power Unit Calculator Power, dBm, dBmV and Volts @ 50 W 2.: The VSWR Calculator Reflection, VSWR, Return loss and Power reflection Reflections, Reflectionl to Mismatch Uncertainty.
03-Jul-1998 | AN-No. 1MA12
Present-day sound studios are hardly conceivable without A/D converters. A/D converters are essential components when music is recorded and they directly influence the recording quality. The current Application Note describes a test program permitting automatic measurements of all parameters of sound studio equipment with the aid of Audio Analyzers UPD or UPL. Measuring converter chips with mostly serial interfaces that are not to standard are not the subject of this Application Note.
26-Jun-1998 | AN-No. 1GA30
In many applications, circuitries with automatic gain control are used, for example in the fields of tape recording or hearing aids. This application note describes the typical characteristic of these control circuitries and the difficulties in measurements using oscilloscops. With the audio analyzers UPL and UPD these measurements can be done much easier, the analysis can be done manually or automatically by using a special software tool.
04-Jun-1998 | AN-No. 1GA32
Many measurements in audio applications have to be monitored for compliance with specified limit values. Therefore, sometimes a whole series of measurements have to be compared with a fixed limit value, in other case it might be necessary to define different tolerances for example for different frequency ranges. Both can be done using Audio Analyzer UPD or UPL. This application note covers the different possibilities of limit checking, it demonstrates how to edit limit files and presents a program to easily generate files for checking the limits of frequency response measurements. Furthermore the display modes for different kinds of references are explained.
04-Jun-1998 | AN-No. 1GA33
In modern telephoning, dual-tone dialling is used more and more often. Every symbol to be transmitted is coded by two frequencies which are sent at the same time. To ensure a trouble-free call setup, transmission has to be done within defined tolerances. For measuring these kind of dialling signals, the measurement equipment has to fulfill high requirements. This application note describes how the measurements can be carried out by using the Audio Analyzers UPL or UPD. It also presents a measuring program for this application.
04-Jun-1998 | AN-No. 1GA23