Welcome to intermod assist intermodulation calculator and frequency coordination software. Passive intermodulation pim scenarios in public safety. The study shall be conducted in a way that analyzes 2nd, 3rd, 5th, and 7th order intermodulation calculations. The most bothersome in a relative narrowband system would be the intermodulation products, as they often appear in band. This result shows that the outofband spectrum density is determined completely by the intermodulation. Anritsu mw82119a is a batteryoperated, high power passive intermodulation testing solution for the major wireless standards in use around the world. Commonly, the 3rd, 5th and 7th order intermodulation signals will be considered. The most prominent during a two tone test would be the intermodulation products at 2f1f2, 2f2f1 and third harmonics at 3f1 and 3f2. It can be a tremendous job to calculate the intermodulation products from. Intermodulation measurements on rf amplifiers rohde. Three sequences describe the frequency sum products. All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only. Ias intermodulation analysis system rf coordination.
There are programs and spreadsheets available online to help with this task. These intercept points, oipn and iipn output or input referred nth order intercept. Introducing the latest, lowcost development in rf intermodulation analysis and frequency coordination intermod assist is a new, groundbreaking software tool specifically designed for the wireless, professional audio industries. Ias intermodulation analysis system rf coordination software pc ias intermodulation analysis system rf coordination software. To define the order, we add the harmonic multiplying constants of the two frequencies producing the intermodulation product. Intermodulation product synonyms, intermodulation product pronunciation, intermodulation product translation, english dictionary definition of intermodulation product. Plo im33rd, 5th, or 7th order im product can be tested for either highside or lowside. The design includes an integrated panel pc with intuitive touch screen interface for. For example, when f im 2f 1 f 2, f im is called the 3rd order intermodulation frequency. Understanding intermodulation distortion measurements. Guidelines for the preparation of an intermodulation. Intermodulation distortion is an important metric of linearity for a wide range of rf and.
This characteristic is dependent upon input levels, as well as operating frequencies and terminating impedance. Distance and relative magnitude of multiple pim sources. To examine intermodulation products we will consider two frequencies f1 and f2 and some of the orders of intermodulation products. Here is what prfintermod reports for the same intermod study. The fcc mandates that antenna owners or licensees must ensure that the rf signal from their sites does not interfere with any existing signals from other carriers, public safety, etc. Improve twotone, thirdorder intermodulation testing. Twotone, thirdorder intermodulation distortion im expresses the degree of nonlinearity of an electronic device that has a definable dynamic range, such as an amplifier or mixer.
Sign up joe stevens pascal intermodulation product calculator for. Field personnel can use the pim master to generate two highpower tones in the transmit band of a base station, and use any of the handheld analyzers to measure the 3rd, 5th, or 7th order intermodulation products in the receive band that travel down the same cable. One popular intermod calculator reports seven third order hits. Third order distortion causes multiple unwanted products. Ix102015 a voltage version mathematical model of intermodulation distortion imd takes the first few often 4 terms of the maclaurin series for the device under test dut voltage transfer function. Higherorder intermodulation products 5th order, 7th order, 9th order are visible at very high input power levels. Intermodulation interference calculations in the land. A novel linearisation technique for reduction in the thirdorder intermodulation distortion products, with injection of second harmonics through a feedback loop of a power amplifier, was applied in this paper. The deviation of the intermodulation product is equal to the sum of each individuals signal deviation, multiplied by the coefficient for that signal indicated in the above formulas. Imd measurement with e5072a ena series network analyzer. Fundamentally, it describes the ratio in db between the power of fundamental tones. In this scenario public safety dl subcarriers cause 3rd, 5th and 7th order intermodulation im and can create interference in the ul. Professional wireless systems is a leader in the wireless audio industry. Intermodulation distortion is an important metric of linearity for a wide range of rf and microwave components.
The output power of the two carriers m1 and m2 increases by about 1 db in each frame, while the 3rd order intermodulation products d3 and d4 grow by 3 db in each frame. The most critical intermodulation distortion product is the third order intermodulation toi product. In modulated signals, thirdorder distortion creates additional frequency. The first and last sum products are unique where the first product location is.
Im3 and im7 have the most critical impact, while im9 cannot be considered as critical. Frequency variation of two or more electromagnetic waves transmitted simultaneously through a. Rf intermodulation calculator,formula for rf intermodulation. Especially the 3rd order intermodulation has to be considered as it results in the. The low order and high order entry fields are normally set to low order of 3 and the high order of 5. This field proven analyzer enables network operators to improve site performance by finding and eliminating sources of passive intermodulation in the rf path. Why you should use frequency coordination software every time. The 3rd order intermodulation signal always represents the worst case condition of unwanted signals. This intermodulation calculator intermodulation study software is software based. The user enters the transmitter and receiver frequencies in mhz with their corresponding bandwidths in khz. Intermodulation product definition of intermodulation. It can be installed on any pc using windows 2000 sp4 or higher, windows xp sp3 or. Passive intermodulation analyzers pim test solutions for.
Interference and intermodulation studies are necessary to determine the potential of any new or modified signals interfering with existing signals, so owners can plan and. The coefficients of the thirdorder imd term in equation 7 can be used as a starting point in the analysis. The intermod calculator provides a checkbox to enable odd order only calculations. Understanding intermodulation distortion measurements electronic. The two tone third order components, 2f1f2 and 2f2f1 are particularly important because unlike 2nd order distortion, i. Intermodulation distortion imd is an important consideration in microwave and rf component design. Intermodulation intermodulation products intermodulation software. In the figure 2 below we can see a typical selfinterference issue. Passive intermodulation analyzer for basestations or. The toi products are usually within or close to the useband, i. The pim masters small size and light weight, combined with battery operation, make it the ideal solution for verifying pim performance at difficult to access sites. Third order intermodulation products of the two signals, f1 and f2, would be. This definition appears very rarely and is found in the following acronym finder categories.
Amplitude of 3rd imd tones 3k3e1 2e 2 2 converting to db provides. A little inspection and thought shows that the majority of these are repeats or phantoms. This is a figure of merit in dbm for the device and normally varies with tuning. The intermodulation products are sum and difference as well as other integer and non integer multiple of these frequencies. Since pim amplitude becomes lower as the order increases, higher order products. Intermod assists computational engine rapidly generates frequency sets of intermodulation distortionfree radio frequencies, applying userdefined signal bandwidths. Rf frequency selectivity parameters at frequency deviations f 1 and f 2 from. Intermodulation im or intermodulation distortion imd is the amplitude modulation of signals. The intermodulation study shall include the citys frequencies, which are listed in table 2. Its computational engine rapidly generates frequency sets of intermodulation distortionfree radio frequencies, applying userdefined signal bandwidths and channel. Intermod assist is a new, groundbreaking software tool specifically designed for the wireless, professional audio and video industries. Interaction of intermodulation products between dut and. The frequency spacing between all of the signals is equal.
This is the power of the spurious 7th order intermodulation signal in. The odd order products, however, produce signals near the input frequencies f 1 2f 2 et f 2 2f 1. Twotone testing for imd has been used to characterize the non. By not checking the checkbox, both odd and even orders are tested which increases the number of calculations and time required for processing. The definition of the thirdorder intermodulation given in equation 9 is the same as for tones used to describe intermodulation distortion in narrowband analysis. Intermodulation radio mobile rf propagation simulation software. Rf intermodulation freeware downloads shareware central. It can be a tremendous job to calculate the intermodulation products from several frequencies, below is a calculator that calculates the intermodulation product from two and three frequencies.
For example, you could hear strong interference at 14. Calculate intermodulation products from 2 and 3 frequencies. Higherorder intermodulation products 5th order, 7th order, 9th order are visible at very high input power levels as the amplifier is driven past saturation. It is generated when two signals are applied to a nonlinear device. Stimulus setup measurement result pf1, sg pf2, ena p lo im3 oip3 pf1 pf2 output power of the main tones and im power level is displayed to calculate output ip3 of the dut. This intuitive tool guides the user through four simple steps to efficiently configure the instrument to measure oddorder intermodulation products 3rd, 5th, 7th and 9th and calculate the associated intercept points. Intermodulation is a source of interference that arises from the combination of two or more signals at different frequencies in some kind of nonlinear system. Therefore, the odd order intermodulation products cannot be removed by filtering, only by improvement in linearity.
Mystic somewhat a contraction of microwave system calculator is an easytouse program which provides you with a smart way to build your rfelectronic design faster and easier. The intermodulation orders shall be analyzed using the maximum number of signals for each order. Low intermodulation amplifiers for rf and microwave wireless systems. Intermodulation calculator intermod study software.