Premiere Synthetic Aperture Radar (SAR) Design Tool for Windows 2000/NT/9x PC-based Systems •Multiple SAR Modes Evaluation and Design Strip (Squint), Scan, Spot •Space- or Aircraft-based •Design from Multiple Perspectives –Antennae Dimensions or Resolutions –Look or Incidence Angle –SNR/Radar Cross-Section or CNR/Scene Reflectivity –Land or Ocean –Adaptive Quantization Option Professional Execution Control with Windows Interface Leads User Thru Design Step-by-Step Specify Ambiguity, Scene-Target, Mission, Radar and System Noise Parameters On-line Help System  Diagrams and Tables Trend-Indicating System Evaluation Graphs Real-time Units System (Metric/English) Switching at any design point  including Summary Sheet and System Evaluation Graphs Save and Print Files and Graph Images Flashing Alerts to Warn User of Potential Design Problems Description RadarCalc 2010 is a space and aircraft-based SAR computer aided design tool developed by User Systems Enterprises, Incorporated for Windows-based personal computers. It is built upon the success of the earlier RADARCALC software from User Systems, Inc., but it is significantly updated both from a technical and user-friendliness standpoint. RadarCalc 2010 was developed for top-level study of mission architectures, SAR radar system feasibility, design and performance trade-off studies and applications verification. Its menu driven structure allows any user to interactively perform SAR remote sensing design calculations.  RadarCalc 2010 calculates all of the appropriate values needed for a synthetic radar aperture design, including ambiguity limits. It is extremely useful for analysis of strip (squint) mapping SARs, scanSAR, and spotlight (SPOT)sar.   RadarCalc 2010 provides for plotting a variety of the most needed graphs and charts that easily present trade analysis studies. An online help system as well as diagrams and tables to aid the user's design are now available. Unit systems switching at any design point can be performed, including on the summary sheet and system evaluation graphs. The design process consists of worksheets that involve:  Ambiguity Parameters Mission and Scene-Target Parameters Radar Parameters System Noise Temperature Receiver Noise Figure Tables Summary Tables Graphing Routines Each worksheet allow the user to modify parameters to their own mission specification These include: Platform altitude, Radar wavelength, Swathwidth, Incidence Angle, Azimuth resolution, PRF, Squint angle, Range resolution Dynamic range (scene), Pulse Compression Ratio, Antenna efficiency, Loss Budget elements. Derived quantities include: Orbit circumference, Revisit latitude circ, Orbital period, Orbit rate, Orbital velocity, Ground track velocity, Look angle, Target range, Ground range resolution, Minimum antenna area, Actual antenna area, Actual antenna dimensions, synthetic aperture length, Range to near/far edge of swath edge, Distance from nadir point to near/ far edge of swath, Unfocused azimuth resolution, Range / Azimuth time bandwidth products, Dwell time, and more..... RadarCalc 2010's Mission Analysis feature enables the user to determine optimum orbits for a system given the basic inputs of orbit inclination and altitude, sensor viewing geometry and coverage requirements. The space platform calculations are based upon circular orbits. RadarCalc 2010's Radar Analysis feature allows the user to determine important radar design parameters, such as antenna noise temperature, system losses, transmit and receive module characteristics based on the latest industry values, and more. Swerling statistics are used to determine signal-to-noise requirements based on probability of detection and false alarm inputs.  Using RadarCalc 2010 WINDOWS MANAGEMENT NOTES I: RadarCalc 2010 uses Windows menu bar type execution control (for example, see the menu bar in the Main Interface window below). This software is designed for monitors of screen resolutions 800 x 600 and greater with most user-friendly use at 1024 x 768 screen resolutions and higher. For all resolutions greater than 800 x 600, the main interface will be oriented towards the top, left corner of the screen. This is intended since many of the windows that can be called up (such as 'help' and 'prior values' windows) on top of the interface can then reside in the screen center and not overlap the interface as severely. This allows the user to interact with the worksheets (enter values for inputs) while the overlap windows are open.  At the 800 x 600 screen resolution, multiple windows can result in a cluttered experience and the user will need to grab the title bar of windows with the mouse and drag them out of the way in order to interact with the worksheets. To leave the Worksheet windows (except for the Conversion Worksheet) requires the user to mouse-click on the 'RETURN' button that resides towards the top-right of the window, or to press the 'Esc' key on the keypad, or go to the menu bar and click on 'File', 'Return'.  This action will also automatically close any overlapping windows as well. (The worksheet windows [except for Conversion worksheet] must be the active window for the keystroke 'Esc' to cause leaving the worksheet.  Just click on the worksheet panel or title bar to make it the active window.) To individually close the overlap windows (help, diagrams, tables, conversion worksheet, prior values), the use should just click on the 'x' at the right-hand side of the title bar of the window.  When many windows are overlapping, activate the one you would like to use by clicking on its title bar or inside its panel.  Move an overlapping window by grabbing its title bar and dragging.  Keep in mind that if for example one of the 'prior values' windows covers up a 'help' window, you can click the title bar or inside the panel of the 'help' window with the mouse to bring that window to the front.  WINDOWS MANAGEMENT NOTES II:  Also note that if running other applications at the same time, the 'windows always on top' property will make the Diagrams, Tables, and Conversion Worksheet windows display over the top of the other application windows. You can close or minimize selected RadarCalc 2010 windows to avoid this using the standard Windows methods (in upper right-hand corner of window, hit 'x' to close and '_' to minimize. However, if the user chooses to minimize worksheet (except for Conversion worksheet) graph, or summary windows, upon their recall these  windows must be interacted with first prior to interacting with Main Interface in order to have proper execution control in RadarCalc 2010. For example, if the 'Ambiguity Tradeoff Worksheet' is called from the main interface window, and all windows are minimized, upon recall the user must interact with, and Return from, the 'Ambiguity Tradeoff Worksheet' window, in order to be able to properly use the main interface window.  If the user finds that he or she cannot interact with the main interface window, check to make sure your worksheets are maximized and in front of the main panel, and finish interacting with those first. Main Interface   General This window is the main calling program for RadarCalc 2010. Select Items from menu bar above. To start a new design with original default values, select from the menu bar 'SAR Main Mode', 'Space' or 'Aircraft'.  The first actions to take are to choose the 'User Options' menu item in the menu bar. Here, you will find selections for SAR Main Mode, SAR submode, and Unit Systems. SAR Main mode allows a choice of (Space [default] or Aircraft) and SAR submode allows a choice of (Strip/Squint [default], Spot, or Scan). Note that the Unit system (metric or english) can be changed within all modules during the design. This can be quite important for showing the design values to designers, end users, and customers in both unit systems without having to start over in a different unit system.  Once the modes and units are chosen, the user can begin the design effort by selecting from the Design Worksheets: Ambiguity Tradeoff, Application, and Radar. The Ambiguity Tradeoff Worksheet must be run first, followed by the Application Worksheet, followed by the Radar Worksheet. The order of interaction with the worksheets IS FORCED and at all times must follow the order listed above.  The software was architected in this manner for the following reason: it forces the designer to observe the effects of changes in prior worksheets (eg. ambiguity) on calculated parameters in subsequent (eg. radar) worksheets. This is absolutely critical since the inputs and outputs from the Ambiguity sheet are used in calculations on the Application Sheet, and the inputs and outputs from both of those sheets are used on the Radar Sheet. Even if a baseline design has been completed and then the user decides to change some parameters on the Ambiguity Tradeoff Worksheet, the user must then return to the Application and Radar sheets, in that order, in order to observe effects and properly recalculate all output parameters (even if no interaction is subsequently required on these sheets). (This also must be done even when reloading a previously-obtained .sar design input file (see the section below entitled Saving & Opening Previously-Saved Files), since output parameters from each sheet must be recalculated.)   This is the iterative, interactive process that defines RadarCalc 2010. The Ambiguity Tradeoff Worksheet is a special page of the program that will indicate any SAR related design ambiguities. Parameters to be specified include resolutions, antennae dimensions, and swath width. The user will have the opportunity to enter alternative values for specific ambiguity related inputs in order to arrive at a valid design. By selecting 'Help' from the menu bar in the Ambiguity Tradeoff Worksheet (and all other modules as well), you have the option to view definitions of parameters (select 'Show Help' under 'Help') and view discussion of SAR design issues related to the worksheet as well as instructions of how to interact with the worksheet (select 'Instructions & Description' under 'Help').  For the Application Worksheet, Mission parameters such as Inclination, Revisit Interval, Revisit Interval, Revisit Latitude are specified (for space-based SAR only). Scene/Target (Viewing Geometry) parameters are also chosen including Signal-to-Noise Ratio, Radar Cross Section, Clutter-to-Noise Ratio, and Scene Reflectivity. For the Radar Worksheet, parameters to be specified include wavelength, pulse compression ratio, and loss budget.  After interacting with the Design Worksheets, the user then has access to all of the run-time menu items in this main window, including Noise Worksheets and System Evaluation. The Noise worksheets allow specification of System Noise Temperature or Noise figures, although RadarCalc 2010 provides baseline default values for these based on current technology. In all worksheet modules discussed above, the user can call up the diagrams, tables, and/or conversion worksheet windows using the 'Show' menu bar item.  These windows can overlap and all be used at the same time. In all modules, greyed out variables (inputs and/or outputs) signify those that are disabled for a particular mode of the program and no user entry is possible for these. The 'help' and 'prior value' windows are also scrollable (help windows only, grab the vertical scroll bar with the mouse, hold left mouse button down, and move mouse up and down), resizable (grab corner with mouse, hold left mouse button down, and resize), and movable (grab title bar with mouse, hold left mouse button down, and move). Saving & Opening Previously-Saved Files Previous design input files (*.sar) can be opened from the main interface, and upon leaving RadarCalc 2010 from the main interface, the user will be prompted as to whether he/she wants to save the design file as it has been constructed to that point.  The .sar design file is saved in an internal format and as such cannot be printed or viewed using an ascii text editor or word processor such as Microsoft Word.  However, in the 'Summary Worksheet' under 'System Evaluation' (see description below), the file, in addition to being saved in the .sar internal format, can also be saved to a .txt or .htm (web page) file for viewing by ascii text editors, word processors, and web browsers. So, to save to a .txt file (or .htm file) one must complete a design and visit the Summary Worksheet first.  Note that some of the other windows such as the graph windows also allow one to save the entire window to image (.png, .bmp) files or to a .htm (web page) file.   Ambiguity Tradeoff Worksheet The Ambiguity Tradeoff Worksheet calculates SAR-Related Design Ambiguities. The SAR designer must consider an ambiguity based minimum antenna area which will limit swath width, along-track resolution or both. This will increase the amount of time that the search pattern will take.  The limit on swath width per aperture requires SAR's to fly higher, use multiple apertures or both to provide wide area coverage.This is a special page of the program that will indicate via Warning Messages any SAR-related design ambiguities regarding the low and high Pulse Repitition Frequency (PRF). Parameters to be specified include resolutions, antennae dimensions, and swath width.  The user must complete this page before proceeding to the other worksheets.  WORKSHEET USE The user can enter alternative values for specific ambiguity related inputs in order to arrive at a valid design. Enter values in the 'User Input' area on the left side of the page by placing the mouse cursor inside the specific control input you would like to change and typing in new values followed by clicking the mouse outside of the control. Alternately, you can click on the up and down arrow/triangle symbols to the left of the control input. The outputs are then shown on the right-hand side of the page.  The user has several options for completing the Ambiguity Tradeoff Worksheet by selecting 'User Options' from the menu bar at the top of the window. The user can choose a 'Resolutions' or 'Antennae Dimensions' mode for design strategy. In 'Resolutions' mode, the Actual Antennae Area is calculated given desired resolutions and swath inputs while in the 'Antennae Dimensions' mode, Actual Antennae Area and Swath are calcuated given desired antennae dimension inputs. For each mode, user input items and calculated outputs are disabled (greyed out) that should not be used / are not applicable for that particular mode. Additionally, the user can choose to start the design with either Incidence or Look (Nadir) angle, and can change from metric to english or english to metric units at any time during the design. Both inputs and outputs will reflect the units change. The units will also change in the floating windows of 'Prior Values from other Worksheets' if you have chosen to view these values from the menu bar. To move the floating windows, left mouse-click on the prior values window and with the mouse button still depressed, drag the window to any desired screen position. Close the floating windows of prior values with by left mouse-clicking on the X in top right corner of the window. The 'User Options' indicators section to the lower right of the window shows the current selections. These are also reflected in the items checked in the menu bar. The values specified on the Ambiguity Tradeoff Worksheet cannot be overriden in subsequent modules of RadarCalc 2010 unless returning to the Ambiguity Tradeoff Worksheet and changing them. The user must complete this page before proceeding to the other worksheets. For obtaining help related to a specific input or output item, select 'Show Help' from the Menu Bar. When 'Show Help' is enabled, placing the mouse over any of the input or output items will result in a pop-up box describing that particular item.  To leave the Worksheet windows (except for the Conversion Worksheet) requires the user to mouse-click on the 'RETURN' button that resides towards the top-right of the window, or to press the 'Esc' key on the keypad, or go to the menu bar and click on 'File', 'Return'.  This action will also automatically close any overlapping windows as well. (The worksheet windows [except for Conversion worksheet] must be the active window for the keystroke 'Esc' to cause leaving the worksheet.  Just click on the worksheet panel or title bar to make it the active window.) To individually close the overlap windows (help, diagrams, tables, conversion worksheet, prior values), the use should just click on the 'x' at the right-hand side of the title bar of the window.  When many windows are overlapping, activate the one you would like to use by clicking on its title bar or inside its panel.  Move an overlapping window by grabbing its title bar and dragging.  If the user chooses to minimize worksheet (except for Conversion worksheet) graph, or summary windows, upon their recall these  windows must be interacted with first prior to interacting with Main Interface in order to have proper execution control in RadarCalc 2010. For example, if the 'Ambiguity Tradeoff Worksheet' is called from the main interface window, and all windows are minimized, upon recall the user must interact with, and Return from, the 'Ambiguity Tradeoff Worksheet' window, in order to be able to properly use the main interface window.  If the user finds that he or she cannot interact with the main interface window, check to make sure your worksheets are maximized and in front of the main panel, and finish interacting with those first. WHAT ARE RANGE AMBIGUITY LIMITS? It would appear that fine along-track resolution can be obtained by simply making the real antenna length small. This is in fact the case, but ambiguity conditions place certain limits on carrying this too far. Pulse Repetition Frequencies (PRFs) for SAR are bounded by range (PRFhigh) and Doppler (PRFlow) ambiguity limits. RANGE AMBIGUITY LIMIT (PRFhigh) The range ambiguity limit establishes an upper limit on pulse repetition frequency (PRF). (See diagram entitled "Geometry for Describing SAR Observations.") The high PRF limit to avoid receiving simultaneous return signals from two successive pulses is given by: PRFHIGH = 1/(2T + 2 (Rf - Rn)/c)  in pulses per second (PPS) where c = the speed of light, T = the real pulse length, and (Rf - Rn) = Wg*sin(fi) where Wg = the radar swath width and fi = the target incidence angle. In practice, the highest operating PRF is set lower than that limit. For space, several pulses will be in transit simultaneously, and to avoid eclipsing the reflected signals, temporal interlacing of returns with the transmitted pulses is required. As swath widths and/or incidence angles increase, more spacing between pulses is required, resulting in a lowering of the high PRF limit. This process will eventually collide with a desire for improved spatial resolution along track, which influences the Doppler ambiguity relationship. ALONG-TRACK DOPPLER AMBIGUITY LIMIT (PRFlow) Doppler relationships produce a low PRF limit that is governed by a maximum phase shift of less than 2p radians from pulse-to-pulse of any target illuminated by the radar beam. If a 2p or greater radian phase shift occurs, there will be ambiguity in distinguishing these targets from other targets at the same range that cause zero phase shift (zero Doppler). There are different approaches to establishing the low PRF limit. In all cases, it is shown that: PRFlow = v/(DAT/2) = 2v/DAT  in pulses per second (PPS) where v = the platform velocity and DAT = the along-track radar antenna length. This can be achieved if the difference in the path lengths equals one-half wavelength. If the ratio of of PRFhigh to PRFlow is near unity, there exists a minimum antennae area that will ensure simultaneous compliance with both ambiguity constraints (PRFlow and PRFhigh). AMBIGUITY WARNINGS AND HAZARDS If the Pulse Repitition Frequency of radar pulses (Select PRF) control having a value selected by the user turns to a pinkish color and a warning box pops up, a problem exists as described below. Problem: The Selected Pulse Repitition Frequency (Select PRF) is either less than 1.2*PRFlow or greater than PRFhigh/1.2. You can continue with design but you are getting close to an invalid design (which you will be further warned about). Action: Either the low limit must be reduced or the high limit increased, or the Select PRF must be adjusted accordingly. To LOWER the low PRF limit: *Decrease Aircraft Velocity (Aircraft-based SAR),  *increase altitude  *Increase Azimuth Resolution To RAISE the high PRF limit: *Decrease Desired Swath Width *Decrease Incidence Angle Discussion: SAR PRF is bounded on both the low and high ends as shown on the Ambiguity page. The low limit is a function of the satellite or aircraft velocity (altitude), the Azimuth Resolution, and the Squint Angle. Increasing the Altitude will lower the velocity, therefore lowering the low PRF limit. In addition, increasing the Azimuth Resolution also lowers the low PRF limit. Also, for the case of Aircraft-based SAR, decreasing the aircraft velocity will also lower the the low PRF limit. The high PRF limit is controlled by the Far to Near Range Distance which in turn is a function of Altitude and Viewing Geometry. The high PRF limit can be raised by lowering either the Desired Swath Width or the Incidence Angle. PRF margin = (PRFhigh - PRFlow). Within-Module Units Conversion Capability May Result in A fraction of a % difference between metric & english values of PRF High Upon Conversion leading to the same difference for PRF Margin. If the PRF Margin Indicator is blinking red and a hazard box pops up, a problem exists as described below. Problem: The Pulse Repetition Frequency ambiguity limits for this design currently overlap (i.e., PRFlow > PRFhigh). Therefore, the system cannot assign an optimal PRF value for this scenario. Action: Either the low limit must be reduced or the high limit increased. To LOWER the low PRF limit: *Decrease Aircraft Velocity (Aircraft-based SAR),  *Increase Altitude  *Increase Azimuth Resolution To RAISE the high PRF limit: *Decrease Desired Swath Width *Decrease Incidence Angle (fi) Discussion: SAR PRF is bounded on both the low and high ends as shown on the Ambiguity page. The low limit is a function of the velocity of the satellite or aircraft (altitude), the Azimuth Resolution, and the Squint Angle. Increasing the Altitude will lower the velocity, therefore lowering the low PRF limit. In addition, increasing the Azimuth Resolution also lowers the low PRF limit. Also, for the case of Aircraft-based SAR, decreasing the aircraft velocity will also lower the the low PRF limit. The high PRF limit is controlled by the Far to Near Range Distance which in turn is a function of Altitude and Viewing Geometry. The high PRF limit can be raised by lowering either the Desired Swath Width or the Incidence Angle. If the Antennae Area Indicator is flashing and a hazard box pops up, a problem exists as described below. (An intermediate condition will be indicated by the indicator text turning a pinkish color and a warning box pops up; this occurs when the actual antennae area < 2*(minimum area). Problem: The current design calls for an antenna area smaller than the minimum antennae area needed based on a  diffraction limited beam. Any area larger than the minimum area shown on the Ambiguity Page will be unambiguous.  Action: Either increase the actual antenna area or decrease the minimum antenna area. To LOWER the Minimum Antenna Area: *Decrease Wavelength (l) (Increase Frequency) *Decrease Incidence Angle (fi) To RAISE the Actual Antenna Area: *Decrease Desired Swath Width (Wg) *Increase Azimuth Resolution If the Swath Width Control and / or Indicator is flashing, a problem exists as described below. Problem: The entered Desired Swath Width (Wg) is larger than the diffraction-limited Maximum Achievable Swath Width.  Action: Either the Desired Swath Width (Wg) must be reduced, or the Maximum Achievable Swath Width must be increased. To LOWER the Desired Swath Width (Wg): *Enter a new value less than or equal to the Maximum Achievable Swath Width. To RAISE Maximum Achievable Swath Width: *Increase Altitude  *Decrease the Incidence Angle (fi) *Increase Azimuth Resolution If the Near-Range Ambiguity Hazard Box pops up, a problem exists as described below.  Problem: The current design places the field of view over the nadir point, which causes errors in the near range incidence angle and ground range resolution. Action: The radar beam needs to be moved away from the nadir which can be done in three ways. *Increase the Incidence Angle (fi). *Increase the Altitude. *Decrease the Swath Width (Wg).   If the Along-track resolution Improvement factor (m) control and dwell angle (a) indicator are flashing, a problem exists as described below: Problem: The current SPOTsar design results in too large of a dwell angle (a) causing inaccurate design results: Dwell Angle (a) = (m)*(l)/(DAT) > 6 degrees. Action: The SPOTsar dwell angle needs to be reduced. *Increase the AT antennae dimension (DAT). *Decrease the AT res. improve. factor (m). *Decrease the wavelength (l).   Application Worksheet Mission design inputs cover orbital characteristics such as inclination and revisit intervals (space-based SAR). Scene/Target (Viewing Geometry) inputs are also specified here and are applications specific and the designer proceeds to calculate mission relevant radar values on the basis of mission inputs. Calculating space and ground velocities are important to aperture dwell determination and orbital characteristics are combined with swath extent to determine revisit intervals at specific latitudes using steered beam. WORKSHEET USE The user can enter alternative values for specific MISSION/ORBIT & SCENE/TARGET inputs in order to arrive at a valid design. Enter values in the 'User Input' area on the left side of the page by placing the mouse cursor inside the specific control input you would like to change and typing in new values followed by clicking the mouse outside of the control. Alternately, you can click on the up and down arrow/triangle symbols to the left of the control input. The outputs are then shown on the right-hand side of the page.  The user has several options for completing the Application Worksheet by selecting user options from the menu bar at the top of the window. The user can choose a Signal-to-Noise/Radar Cross-Section' or 'Clutter-to-Noise/Scene Reflectivity' mode for design strategy. These modes will affect subsequent calculations of power on the upcoming Radar Worksheet. For each mode, user input items are diabled (greyed out) that should not be used. Additionally, the user can change from metric to english or english to metric units at any time during the design by choosing 'Units' under the 'User Options' menu item. Both inputs and outputs will reflect the units change. The units will also change in the floating windows of 'Prior Values from other Worksheets' if you have chosen to view these values from the menu bar. To move the floating windows, left mouse-click on the prior values window and with the mouse button still depressed, drag the window to any desired screen position. Close the floating windows of prior values with by left mouse-clicking on the X in top right corner of the window. The 'User Options' indicators section to the lower right of the window shows the current selections. These are also reflected in the items checked in the menu bar. The user must complete this page before proceeding to the Radar worksheet. For obtaining help related to a specific input or output item, select 'Show Help' from the Menu Bar. When 'Show Help' is enabled, placing the mouse over any of the input or output items will result in a pop-up box describing that particular item. To leave the Worksheet windows (except for the Conversion Worksheet) requires the user to mouse-click on the 'RETURN' button that resides towards the top-right of the window, or to press the 'Esc' key on the keypad, or go to the menu bar and click on 'File', 'Return'.  This action will also automatically close any overlapping windows as well. (The worksheet windows [except for Conversion worksheet] must be the active window for the keystroke 'Esc' to cause leaving the worksheet.  Just click on the worksheet panel or title bar to make it the active window.) To individually close the overlap windows (help, diagrams, tables, conversion worksheet, prior values), the use should just click on the 'x' at the right-hand side of the title bar of the window.  When many windows are overlapping, activate the one you would like to use by clicking on its title bar or inside its panel.  Move an overlapping window by grabbing its title bar and dragging.  If the user chooses to minimize worksheet (except for Conversion worksheet) graph, or summary windows, upon their recall these  windows must be interacted with first prior to interacting with Main Interface in order to have proper execution control in RadarCalc 2010. For example, if the 'Ambiguity Tradeoff Worksheet' is called from the main interface window, and all windows are minimized, upon recall the user must interact with, and Return from, the 'Ambiguity Tradeoff Worksheet' window, in order to be able to properly use the main interface window.  If the user finds that he or she cannot interact with the main interface window, check to make sure your worksheets are maximized and in front of the main panel, and finish interacting with those first.   Radar Worksheet Radar Parameters include Antenna Efficiency, Pulse Compression Ratio, and Loss Budget and are specified in this sheet. WORKSHEET USE The user can enter alternative values for specific RADAR inputs in order to arrive at a valid design. Enter values in the 'User Input' area on the left side of the page by placing the mouse cursor inside the specific control input you would like to change and typing in new values followed by clicking the mouse outside of the control. Alternately, you can click on the up and down arrow/triangle symbols to the left of the control input. The outputs are then shown on the right-hand side of the page.  The user has several options for completing the Radar Worksheet by selecting 'User Options' from the menu bar at the top of the window. Menu options include 'User Mode' (Signal-to-Noise Ratio/Radar Cross-Section mode or Clutter-to-Noise Ratio/Scene Reflectivity Mode), 'BAQ' (Adaptive Quantization) Mode (yes/no), 'Receiver Noise Mode' (Discrete/Hybrid or MMIC). (The Receiver Noise Mode option is disabled if the user has entered the System Noise Temperature Worksheet and used any other mode besides 'Baseline Default' for calculation of System Noise Temperature. This is because it is not applicable in the other modes.) The operating area is defaulted to Land but can be changed in the System Temperature Noise Worksheet to Ocean if desired. These options can be toggled at any time during the design. Additionally, the user can change from metric to english or english to metric units at any time during the design. Both inputs and outputs will reflect the units change. The units will also change in the floating windows of 'Prior Values from other Worksheets' if you have chosen to view these values from the menu bar. To move the floating windows, left mouse-click on the prior values window and with the mouse button still depressed, drag the window to any desired screen position. Close the floating windows of prior values with by left mouse-clicking on the X in top right corner of the window. The 'User Options' section to the lower right of the window shows the current selections. These are also reflected in the items checked in the menu bar. The user must complete this page before proceeding to the Noise worksheet. For obtaining help related to a specific input or output item, select 'Show Help' from the Menu Bar. When 'Show Help' is enabled, placing the mouse over any of the input or output items will result in a pop-up box describing that particular item. To leave the Worksheet windows (except for the Conversion Worksheet) requires the user to mouse-click on the 'RETURN' button that resides towards the top-right of the window, or to press the 'Esc' key on the keypad, or go to the menu bar and click on 'File', 'Return'.  This action will also automatically close any overlapping windows as well. (The worksheet windows [except for Conversion worksheet] must be the active window for the keystroke 'Esc' to cause leaving the worksheet.  Just click on the worksheet panel or title bar to make it the active window.) To individually close the overlap windows (help, diagrams, tables, conversion worksheet, prior values), the use should just click on the 'x' at the right-hand side of the title bar of the window.  When many windows are overlapping, activate the one you would like to use by clicking on its title bar or inside its panel.  Move an overlapping window by grabbing its title bar and dragging.  If the user chooses to minimize worksheet (except for Conversion worksheet) graph, or summary windows, upon their recall these  windows must be interacted with first prior to interacting with Main Interface in order to have proper execution control in RadarCalc 2010. For example, if the 'Ambiguity Tradeoff Worksheet' is called from the main interface window, and all windows are minimized, upon recall the user must interact with, and Return from, the 'Ambiguity Tradeoff Worksheet' window, in order to be able to properly use the main interface window.  If the user finds that he or she cannot interact with the main interface window, check to make sure your worksheets are maximized and in front of the main panel, and finish interacting with those first.   System Noise Temperature Worksheet This Sheet allows the user to specify operating area, receiver noise figure, receiver line loss, and / or system noise temperature directly. WORKSHEET USE The user can enter alternative values for specific SYSTEM NOISE TEMPERATURE inputs in order to arrive at a valid design. First, the user needs to select from the 'User Options' menu the 'Specification Mode' which will enable / disable specific user inputs. Initially, the output values as calculated from the RADAR sheet will be used. For 'dB Noise Levels' mode, the user can enter values for Receiver Noise Figure and Reciever Line Loss resulting in calculations of corresponding temperatures including System Noise Temperature. For 'System Noise Temperature' mode, the user directly enters the value for this parameter. 'Baseline Default' mode will revert to the system noise temperature automatically calculated in the radar sheet with one caveat. If the user changes the 'Operating Area' in this worksheet, this will modify the original baseline default calculation. The 'Operating Area' can be toggled from land to ocean and will affect calculations in the RADAR worksheet such as average and peak power. Note: In the Radar Worksheet, the Receiver Noise Mode option is disabled if the user has entered the System Noise Temperature Worksheet and used any other mode besides 'Baseline Default' for calculation of System Noise Temperature. This is because it is not applicable in the other modes.  Enter values in the 'User Input' area on the left side of the page by placing the mouse cursor inside the specific control input you would like to change and typing in new values followed by clicking the mouse outside of the control. Alternately, you can click on the up and down arrow/triangle symbols to the left of the control input. The outputs are then shown on the right-hand side of the page.  The 'User Options' & 'Message' section in the lower area of the window shows the current selections and important status messages. The former are also reflected in the items checked in the menu bar. For obtaining help related to a specific input or output item, select 'Show Help' from the Menu Bar. When 'Show Help' is enabled, placing the mouse over any of the input or output items will result in a pop-up box describing that particular item. To leave the Worksheet windows (except for the Conversion Worksheet) requires the user to mouse-click on the 'RETURN' button that resides towards the top-right of the window, or to press the 'Esc' key on the keypad, or go to the menu bar and click on 'File', 'Return'.  This action will also automatically close any overlapping windows as well. (The worksheet windows [except for Conversion worksheet] must be the active window for the keystroke 'Esc' to cause leaving the worksheet.  Just click on the worksheet panel or title bar to make it the active window.) To individually close the overlap windows (help, diagrams, tables, conversion worksheet, prior values), the use should just click on the 'x' at the right-hand side of the title bar of the window.  When many windows are overlapping, activate the one you would like to use by clicking on its title bar or inside its panel.  Move an overlapping window by grabbing its title bar and dragging.  If the user chooses to minimize worksheet (except for Conversion worksheet) graph, or summary windows, upon their recall these  windows must be interacted with first prior to interacting with Main Interface in order to have proper execution control in RadarCalc 2010. For example, if the 'Ambiguity Tradeoff Worksheet' is called from the main interface window, and all windows are minimized, upon recall the user must interact with, and Return from, the 'Ambiguity Tradeoff Worksheet' window, in order to be able to properly use the main interface window.  If the user finds that he or she cannot interact with the main interface window, check to make sure your worksheets are maximized and in front of the main panel, and finish interacting with those first.   System Evaluation At the design completion, from the main interface, the user can choose to view a summary of the design and trend-indicating graphs by choosing options from the 'System Evaluation' menu item.  These windows are shown below.  The user can choose to save a design from the Summary Worksheet by choosing 'save' under the 'file' menu item.  Saving here will save the design to a '*.sar' file (in binary format) that can be reloaded from the main interface at a later time.  At the save time, an ascii text type file (*.txt) will be saved that can be opened and printed out by ascii text editors such as Notepad and word processors such as Microsoft Word.  Under the 'file' menu item on the Summary Worksheet, one can also choose to print out the design as it appears on the worksheet.  The printing of the design data will occur on one page in a landscape format.  The user can also choose to print out this information to a *.htm file (web page) that can be opened in any web browser.   In the graphs windows, the user can choose to print out this information to a *.htm file (web page) that can be opened in any web browser, or print to a .png or .bmp graphic file.   Other Features Within the worksheets and also in some cases the main interface, the user can use the 'Show' menu item to view prior calculated values from the other worksheets, diagrams, tables, and conversions.  The user can also view the instructions, and item descriptions by selections from the 'Help' menu item.  These windows are shown below.     For the Diagrams window shown below, use the yellow ring control to select from all of the different diagrams available. For the Tables window shown below, Use the ring control to select from all of the different tables available. Copyright © 2010 User Systems Enterprises, Inc., All Rights Reserved