Capturing the segment of spectrum of interest, from minutes to hours, allows a technician to return to the lab with data necessary to diagnose and solve the problem, while building a library of environments to harden their products for the future, Averna said. Simulators can bring the design up to a certain point in the development process, but Averna’s RF Recorder captures all the multi-path, interference and general degradation of signals that end-users will experience. Wireless products need to perform well in the complicated and difficult-to-predict RF environments found in the real world. Its compact size and integrated display was designed for field operation. With 50 MHz of recording bandwidth at 16-bits, it can record multiple GNSS signals in up to two bands (L1, L2, L5), such as GPS or GLONASS. The Averna RP-5300 RF Recorder is an advanced tool for both field testing and performance testing, Averna said. Revision History( from latest back to first release):įrequency Spread is now continuous from 0.1 to 30Hz.įixed Problems with non-Gaussian LP filters.Īdded user selectable items to save with the simulation.įixed Problems with Run Time calculation.Averna, developer of test solutions and services for communications and electronics device makers, announces the availability of a field-ready multi-channel RF Recorder for RF applications covering 330 MHz to 2.5 GHz. MathCad Files used in the Gaussian LP filter and Hilbert BP designs(6K): MathCADfiles.zip Project Source Code released under GPL(62K): PathSimSrc10.zip User/Technical manual with design verification data(593K): PathSimTech100.pdf This Program is made available free of charge for amateur radio use only.Įxecutable, Help, and some canned simulation setups(371K): PathSim10.zip Not sure why you would want to do this but it is kinda neat to play with. The frequency offset of one path can be used to shift an incoming frequency spectrum by up to +/- 1000 Hz. The recording time length can be set from 1 to 500 minutes. The recorder eats up about a megabyte per minute so an hour needs about 60 megs of disk space. As a side feature, a delayed record start is implemented so this program can be used to record audio at some future specified UTC time. Note that only 8000KHz 16 bit samples are supported. If the AWGN generator and the HF paths are turned off, then the program works like a digital recorder so one can record and playback wave files using the soundcard as a signal source or destination. The other problem is there can be a large output swing even though the rms is small due to the summing of all the paths. 5mSec or 180deg, then the output signal will be zero since the two paths cancel each other exactly. If a 1KHz signal is input, and you have two paths that delay the input by. The HF Paths are all calibrated to have unity gain for any combination of settings. The time plot turns red if you are overdriving the 16 bit soundcard/wavefiles. A small fft and realtime output plot are available to monitor output signals. The noise and signal are then added to produce the final output signal. There are two gain/attenuator blocks that are varied to achieve the desired S/N ratio in dB. The input signal's rms "voltage" is measured and averaged over a second or so. The AWGN source is filtered by a 3KHz LP filter to bandwidth limit the noise. Just the I or real term of the three paths are summed together to create a real output.īasically here's how the S/N ratio is achieved. The spreading is performed by low pass filtering a complex AWGN signal to the desired bandwidth and then multiplying by the incoming complex signal.Įach path also has a frequency offset function which is just a complex NCO that is multiplied by the incoming signal. Three paths are then created with two of them having a variable time delay.Įach Path has a Spreading frequency selection and a frequency offset parameter. It is first bandpass filtered and converted to an I/Q complex signal using a Hilbert transform(incorporated in the bandpass filter). The real input signal can come from either the soundcard or a wave file. A set of canned simulations are included in this zip file and are somewhat standard test conditions. Three HF paths are available though usually only two are used.Įach simulation "session" can be titled and saved to a file for future retrieval. The main screen is fairly descriptive of the signal processing paths. PathSim is a Windows program that can be used to simulate radio propagation paths using a soundcard and/or wave files as the source and destination.
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