This easy-to-use software program includes extensive Help files to guide a first-time user through its functions.           

Preventing these responses is a critical step in receiver design. Unfortunately, most receiver architectures cannot differentiate between a real or a spurious signal that appears at the receiver's intermediate frequency (IF). These responses can appear as valid signals unless the RF spectrum of interest is filtered after the antenna. Fortunately, a low-cost personal computer (PC) program from The Engineers' Club (San Jose, CA) known as MxrSpur enables designers to visually scan RF and local oscillator (LO) bands of interest as well as locate spurious responses that fall within the IF band. With this convenient software tool, engineers can quickly optimize a receiver's IF band for fixed RF and LO frequencies.

This cost-effective and  easy-to-use program used as a dedicated calculator for mixer spurious products. An operator needs to simply specify LO and RF parameters, then define the measurement limits of the virtual spectrum analyzer within the software that is used to display the resulting spurious products. Spectrum analyzer definitions can include any RF or IF of interest. Once the desired parameters have been entered, an operator merely clicks on a Solve Matrix button and the analysis is quickly completed, with computational speed a function of the computing power and the size of the matrix (the total number of spurious products) selected by the operator. Users can step the array one frequency at a time and observe the spurious frequency as well as levels in the analyzer window. Other controls consist of single or 10 repetitive sweeps and a choice of 12 sweep speeds.

The program enables operators to enter the performance parameters of a mixer under consideration for their receiver design. For example, a user can define mixer parameters such as conversion loss, RF-to-IF isolation, and LO-to-IF isolation. Frequency can be entered in kilohertz, megahertz, or gigahertz. Variable menu functions include frequency units, mixer parameters, and a user-defined label function that can be accessed by checking a box next to the program's Engineers' Club logo. A print button enables operators to send the results of an analysis (as a bitmap or BMP file) to a wide range of printers for creation of hard-copy documentation.

CALCULATING RESPONSES ;
Calculating spurious responses consists of mixing each LO harmonic frequency with each RF harmonic frequency. While infinitely many spurious products can be produced by these signal interactions, only signals that fall within a user-defined spectrum analyzer sweep window will be displayed as calculated results. Any signals that fall within the spectrum analyzer window parameters are recorded in a spurious matrix chart. Spurious responses are cataloged in three-element array, with the first element representing frequency, the second element representing the harmonic of the LO (denoted as N), and the third element representing the harmonic of the RF signal (denoted M). The maximum user-specified array size is 12 LO frequencies, 12 RFs, and 100 frequencies. Arrays of all sizes are shown on a spectrum analyzer-like display screen.
   
This easy-to-use software program includes extensive Help files to guide a first-time user through its functions. The help files contain tutorial lessons, background information on the theory of operation, and a list of control functions. Additional topics cover menu functions, the mouse pointer tool, a glossary of terms, and a list of defined parameters.

P&A $49.95 - stock.
The Engineers' Club,

1737 Silverwood Dr. San Jose, CA, 95124
Ph (408) 316-0488
e-mail INFO@engineers.com
Internet http://www.engineers.com.

ALAN CONRAD
Special Projects Editor

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