Rf measurements tutorial rf device test and measurement. Pulse measurement techniques are illustrated by way of device measurement problems, which makes the chapter more. The measurement technique is described in detail in application notes such as keysight application note 572 noise figure measurement accuracy the yfactor method. Also, certain parameters need to be set up in the noise figure meter before the measurement, such as frequency range, application amplifiermixer, etc. Minimize uncertainties wherever that is possible 3. A mixer may be necessary if you want to convert the rf frequencies to desired if frequencies.
Keysight technologies nfa series noise figure analyzers keysight technologies psa series spectrum analyzers with noise figure measurement personality. Magnetic loops have long been used by emc personnel to sniff out sources of emissions in circuits and equipment. The later chapters, in particular, include more advanced and sourcespecific noise control technology. Enable browser cookies for improved site capabilities and performance. Theory and measurement techniques for the noise figure of. Pdf a novel noise measurement method for mixers which exploits mixer noise figure variation with lo power is reported. Noise data contains amplitude, frequency, time or phase information, which allows us to. Agilent technologies nfaseries noise figure analyzers introduced in 2000 agilent technologies 8970series and similar. Superposition of am and fm spectrum unequal carrier side bands. Background equations are presented for each step of the calculation. Aug 14, 2012 this book provides stateoftheart coverage for making measurements on rf and microwave components, both active and passive. A paradigmatic example is the hp8970 and associated family that was considered for years as the reference meter for noise figure characterization. Spectrum analyzers with noise figure measurement personality software. The goal of the noise figure application is to accurately measure the noise that is generated by the dut.
Practice all the different settings video bandwidth, resolution bandwidth etc. Feb 12, 2019 the y factor technique for noise figure measurements this application note describes in detail the steps required to make a noise figure measurement on a spectrum analyzer using the y factor technique. Corrections related to match and gain, microwave j. Noise figure measurement without a noise source on a vector. An intriguing chapter on pulse characterization ends the book. Signal and noise measurement techniques using magnetic. The y factor technique for noise figure measurements rohde.
Hebard university of florida, gainesville, fl august 4, 1999 abstract the noise of a resistive sample is a measurable physical property. Pdf a new technique for noise figure measurements of millimetre. Then the power measurement technique, which includes the power gain compression, harmonic distortion and intermodulation distortion measurements. Noise figure is the parameter that is seen widely in specifications and in use when defining radio receivers and the elements within the receiver systems. It is a number by which the performance of an amplifier or a radio receiver can be specified, with lower values indicating better performance. In case you dont need a frequency mixer, simply connect the if out cable to the noise source, and calibrate. Once additional noise joins the signals, receiver performance will be degraded.
Agilent technologies nfa series noise figure analyzers agilent technologies psa series spectrum analyzer with noise figure measurement personality. If a premium product has a maximum specified noise figure of 2. Using a noise figure meter is the most straightforward way to measure noise figure. Application note of noise figure measurement methods. These basic concepts covered in application note 571 are expanded on in chapter 2 of this application note. Using noise figure meter excess noise ratio enr of noise source. A practical guide to theory, measurement, and circuits is a comprehensive and readable treatment of rf and microwave engineering.
Topics covered include microwave instrumentation, such as network analyzers, realtime spectrum analyzers and microwave synthesizers. Gain method, yfactor method, and the noise figure meter method. Oldest phase noise measurement method simplest and easiest method of phase noise measurement the device under test dut is directly connected to the input of a spectrum analyzer the analyzer is tuned to the carrier frequency directly measure. To reduce the noise variance, a statistical approach must be undertaken. The equipment connections are as shown in the diagram below. Grouppresentation title agilent restricted month november, 2005 definition in terms of noise. In case you dont need a frequency mixer, simply connect the if out cable to the noise. Three methods of noise figure measurement tutorial maxim. Signal and noise measurement techniques using magnetic field probes douglas c. The material included in this book is limited to that which is clearly applicable to nonaerospace industrial noise control problems.
The title of the book says advanced and some of the techniques are certainly advanced like for example vector corrected noise figure measurements. Microwave measurements exploit a number of tools that are also commonly. Many instruments use the yfactor technique, including. This is a measure of how far a signal pokes through the noise floor. Fiber optic measurement techniques is an indispensable collection of key optical measurement techniques essential for developing and characterizing todays photonic devices and fiber optic systems. Coldsource noise figure measurement method the coldsource noise figure measurement method was developed to eliminate the requirement for a multistate noise source, which would allow the use of a simpler, better controlled noise source nominally a termination at room temperature. In extreme cases, it is no longer possible to distinguish. Fundamentals of noise figure measurement using the yfactor method. The n9069a noise figure measurement application is one in a common library of more than 25 measurement applications in the keysight xseries, an evolutionary approach to signal analysis that spans instrumentation, measurements and software. The combined noise figure of the filter, mixer and if amp which follow is 12 db, yet it only degrades the noise figure of the entire lineup by 0.
Noise figure nf and noise factor f are measures of degradation of the signalto noise ratio snr, caused by components in a signal chain. Noise figure measurements are essential to ensure that minimal noise is added to the receiver chain of the device. Three methods of noise figure measurement nov 21, 2003 abstract. Introduction in wireless communication systems, the noise figure nf, or the. In addition, guidelines are provided to ensure a repeatable measurement.
Microwave measurements chapter 9 microwave electronics. Agilent tutorial notes, noise figure measurement accuracy the yfactor method, application note 572, 2005. The book gives comprehensive and systematic descriptions of various fiber optic measurement methods with the emphasis on the understanding of. However, the first step is to determine if there is a noise problem in the workplace.
Measurements of several types of modulation am fm pm in the time and frequency domain. Think of noise figure as the ratio of snr in to snr out see noise figure for measurement techniques through any rf component or system. The book gives comprehensive and systematic descriptions of various fiber optic measurement. Noise figure and measurement techniques a practical approach. It is related to noise temperature as mentioned below. Practical measurement techniques are presented in detail, including the use of network analyzers, sampling oscilloscopes, spectrum analyzers, and noise figure meters. The advantage of this method is the simple system configuration, but the disadvantage is the need for a highperformance measuring. Explore information on rf and microwave noise figure measurements, including noise figure and temperature, noise characteristics, and the measurement of. Handbook of microwave component measurements wiley.
Noise and how to deal with it on a fullgrown coast live oak there are, by rough estimate, over a million leaves, in general all the same, but in detail, all di erent. I mentioned that you need to measure an amplifiers noise power to calculate its noise figure. Techniques for using the rtl dongle for detecting meteors dr david morgan. Explore information on rf and microwave noise figure measurements, including noise figure and temperature, noise characteristics, and the measurement of noise figure. It is shown that when the noise figure is defined in terms of the input and output signalto noise ratios, the formulation provides a consistent theoretical formulation for measurement techniques using optical and optoelectronic measurement methods. Factors that you need to consider when choosing equipment for noise figure. The noise figure uses a logarithmic scale and is simply the noise factor expressed in decibels. Connectors and cables are also described, as are discrete passive components, antennas, low noise amplifiers, oscillators, and frequency synthesizers. One popular approach is known as the welch or periodogram averaging method. Optimize selection of noise control devices, methods, materials 3. Noise measurement an overview sciencedirect topics. The measurement technique is described in detail in application notes such as keysight application note 572 noise figure measurement. As a matter of principle, the noise figure of the entire system is always dominated by the first amplifier in the system. An engineer can measure the noise figure over a certain frequency range, and the analyzer can display the system gain together with the noise figure to help the measurement.
A guide to noise measurement terminology cirrus research. The term excess noise ratio is primarily used in connection with noise diodes which are a common method of measuring the noise performance of an amplifier. When recording gps signals, it is necessary to determine the noise figure. Oldest phase noise measurement method simplest and easiest method of phase noise measurement the device under test dut is directly connected to the input of a spectrum analyzer the analyzer is tuned to the carrier frequency directly measure the power spectral density of the oscillator in terms of. Several types of dedicated and generalpurpose instruments can measure noise power as well as noise figure. Modern rf and microwave measurement techniques the. Highaccuracy noise figure measurements using the pnax. Noise figure measurement it is the measure of the amount of noise generated by amplifierdut. The advantage of this method is the simple system configuration, but the disadvantage is the need for a highperformance measuring instrument. Agilent fundamentals of rf and microwave noise figure. This document briefly outlines the steps involved in the noise measurement.
The basic methods of measurement of noise figure and noise. Like ngerprints, no one leaf is exactly like any other. Effects of dut mismatch on the noise figure characterization. Fundamentals of rf and microwave noise figure measurements. Noise figure measurement methods and formulas maxim. Accelerometer principles and vibration measurements. As such, some of the material is not very relevant to users of older, less advanced vnas like my 20 ghz hp 8720d. There are atleast three ways to measure the noise figure of a device. Modern rf and microwave measurement techniques edited by valeria teppati june. Spectrum lab waterfall plot for the 10khz noise measurement is shown in figure 7. This application note is specific to instruments that use the yfactor method for noise figure measurement. Emphasis has been placed on fan noise reduction, noise transmission control techniques, and jet noise suppression. Noise figure measurement accuracy the yfactor method. Three different methods to measure noise figure are presented.
Well cover the topic of noise figure measurement another day. The choice depends on the workplace noise and the information needed. If a dft is performed on the data to estimate the power of the frequencies in the signal, the expected noise in the measurement is of the same size as the measurement itself. Agilent technologies makes no warranty of any kind with regard to this material. The noise perts a guide to noise measurement terminology a summary of parameters and functions shown by the optimus sound level meters, trojan noise nuisance recorder and dosebadge noise dosimeter.
Smith auspex systems 2300 central expressway santa clara, ca 95050 phone. Noise figure measurements of circuits and subsystems have been traditionally performed with noise figure meters specifically developed for that purpose. The most commonly used method is called the yfactor or hotcoldsource technique, and it is used with agilents noise figure analyzers, and spectrum analyzerbased solutions. Signal and noise measurement techniques using magnetic field. Noise figure characterization chapter 10 modern rf and. N9069a noise figure measurement application discontinued. Noise figure is a figure of merit in rf systems and components, and can be determined from noise measurement technique by using the yfactor method. It is shown that when the noise figure is defined in terms of the input and output signalto noise ratios, the formulation provides a consistent theoretical formulation for measurement techniques. Types of signals and proper measurement techniques. Related agilent technologies literature and web resources appear later in this application note.
A measurement instrument should respond to noise power and offer a bandwidth at least 10 times that of a uuts noise. The test setup for amplifiers using an automatic noise figure meter is simple, as shown in figure 4, although much sophistication is implemented in such an instrument. Keysight technologies noise figure measurement accuracy the. The early chapters provide a theoretical basis for measurements. Keysight technologies noise figure measurement accuracy. The 23 chapters of the book cover everything from the history of radio to using probes. A simpler low pass filter can also be used as shown in figure 2, if noise measurements are to be made in the hf or low vhf bands. Noise and vibration measurements handbook of noise and. Aug 30, 2004 connectors and cables are also described, as are discrete passive components, antennas, low noise amplifiers, oscillators, and frequency synthesizers.
In the direct method, a spectrum analyzer is used to measure the absolute power of the noise and the. In our example above, the preselector filterlna had 19. Noise figure measurement techniques there are two main techniques for making noise figure measurements. Noise figure nf is a measure of degradation of the signalto noise ratio snr caused by the noise generated within a system. Noise figure measurements of circuits and subsystems have been. Connectors and cables are also described, as are discrete passive components, antennas, lownoise amplifiers, oscillators, and frequency synthesizers. The equations developed in this chapter follow the internal calculation route of the agilent technologies nfa series noise figure analyzers. This book provides stateoftheart coverage for making measurements on rf and microwave components, both active and passive. Noise figure and measurement techniques a practical. Instrumentation and measurement, ieee transactions on 51 6. This may be done using special low noise receivers or using the standard vna receivers depending on whether the vna has options 029 or 02.
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