DriveTest Manual Guide

Uploaded by: Engr. M. Basharat Ali Awan Email: [email protected]

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PREFACE ...........................................................................................................................2 DRIVE TEST USING TEMS ..............................................................................................2 2.1 Preparation for Drive Test ........................................................................................2 2.1.1 MapInfo Preparation ............................................................................................2 2.1.2 TEMS Preparation ...............................................................................................9 2.2 Implementation of Drive Test Using TEMS ........................................................... 11 2.2.1 Map Configuration ............................................................................................. 11 2.2.2 Hardware Configuration ..................................................................................... 15 2.2.3 Enabling External Equipments (Hardware) ........................................................ 16 2.2.4 Drive Test Implementation Proper...................................................................... 19 While on drive test you can also perform the following: ............................................................ 20 3 DRIVE TEST ANALYSIS USING TEMS AND MAPINFO ............................................ 21 3.1 Analyze by TEMS Replay...................................................................................... 21 Replaying Logfiles ............................................................................................................ 21 3.1.1 Interference Problem Analysis ........................................................................... 21 3.1.2 Missing Neighbor Problem Analysis .................................................................. 23 3.1.3 Call Drop Problem Analysis ............................................................................... 24 3.1.4 Handover Problem Analysis ............................................................................... 24 3.1.5 Coverage Problem Analysis ............................................................................... 24 3.2 Analyze by TEMS Export ...................................................................................... 25 Executing the Export Orders.............................................................................................. 29 3.3 Analyze by Generating Report ............................................................................... 30 Report Contents................................................................................................................. 36 3.3 Analyze Using MapInfo ......................................................................................... 36 3.3.1 Show RxLev Map by MapInfo ........................................................................... 36 Creating Thematic Map ..................................................................................................... 39 3.3.2 Show RxQual Map by MapInfo ......................................................................... 49 3.3.3 Sector Swap Problem ......................................................................................... 50 4.0 Tems cel file created skill .................................................................................................... 54

1

PREFACE

The Getting Started Manual deals with preliminaries that you must work through before you can carry out DRIVE TEST, such as Preparation of input data, hardware and software configuration (TEMS Mobile and GPS). The manual also covers how you can analyze data using MapInfo and TEMS Investigation GSM after drive test. The User’s Manual is what you will probably be referring to most of the time once you have gotten started. The summary of the drive test is stated below:        

Before drive test, prepare input data (in .txt format and .cel format) Creating points using map info Map configuration Hardware Configuration Enabling external devices Perform drive test and save log files Exporting logfiles and generating reports using TEMS Investigation software and Drive test report.

2

DRIVE TEST USING TEMS

2.1

Preparation for Drive Test Before drive test implementation, the input data need to be prepared in which without it, drive test cannot be successfully carried out. And this input data can be prepared using MapInfo and TEMS as will be discussed in the following sections.

2.1.1 MapInfo Preparation To launch MapInfo: Choose Start > Programs > MapInfo >MapInfo Professional 6.5 or simply click on the short cut on your desktop if one is created. For MapInfo preparation, you need to prepare your table in Excel spreadsheet (see Fig. 1) which should include the following: Site ID and Co-ordinates (Longitude and Latitude).

Fig. 1.

Input table in excel (xls) format

The above table should be saved as a text file (using Save As) before uploading in MapInfo because with MapInfo you can upload table in text (txt) format Note: Always remember where you save your files for easy location. To upload table in MapInfo, simply follow the steps below: Steps 1. From the tool bar or menu bar of MapInfo window click on Open. The Open Table dialog window will appear

Fig. 2. File name Files of type Preferred View

Open Table dialog

Select file name where saved Select “Delimited ASCII (*.txt)” Change from “Automatic” to “Current Mapper”

Click Open 3. Delimited ASCII Information window will pop-up as shown below:

Fig. 3. Check

Delimited ASCII Information window

“Use First Line for Column Tiles” and click OK

The result as shown below will be displayed

Fig. 4.

MapInfo table format

Note: The above table is in MapInfo table format (e.g. DT.TAB). Also note that the co-ordinates are in decimal.

After Creating MapInfo table format as shown above. The next step is to create points. How do you create points? Simply follow the path below: From the menu bar click on Map > Create Points. Create Points window comes up as shown below.

Fig. 5.

Create Points window

Get X Coordinates from Column

Select Long for this column

Get Y Coordinates from Column

Select Lat for this column

After selection click OK To display points created choose Window > New Map from the menu bar and these points are displayed as shown below:

Fig. 6.

Created points

The points created can be zoomed by clicking on “zoom-in or zoom-out” bar. You can label points created by clicking label.

from the tool

Layer Control on the tool bar and check

auto

Fig. 7.

Layer Control window

Click OK The window below will be displayed

Fig. 8.

Labeled points

2.1.2 TEMS Preparation To launch TEMS Choose Start > Programs > TEMS Product > TEMS Investigation GSM 4.0 or click on the short cut on your desktop if on is created. For TEMS preparation, you need to prepare your table in Excel spreadsheet (see Fig. 8) which should include the following: CELL NAME, ARFCN, BSIC, LATITUDE, LOGITUDE, CGI (MCC, MNC, LAC, and CI), ANTENNA DIRECTION, ANTENNA BEAM WIDTH etc as shown in fig. 9 below

Fig. 9.

input table in excel format

Note: the above table should be saved as text file (using Save As) then change the text file extension by renaming the extension .txt to .cel which can now be uploaded in TEMS Investigation GSM 4.0. Also note that the co-ordinates (Latitude & Longitude) of fig. 8 are in degree and minutes while in fig. 1 are in decimal.

Co-ordinate Format Please note that the co-ordinates used in TEMS have a format as shown below. For Latitude there must be a space between the N and XXXXX.XXXX (e.g. N 01109.8001) and also note that the first three X is in degree while the rest in minutes.

Fig. 10.

Format for Latitude

Note: If the number of digits is not enough (or complete) as shown in the format (fig. 10), you have to make-up for the remaining digit(s). E.g. if latitude is N 1106.7830. From the example you will notice that the degree part is not complete (only two digits instead of three digits). Therefore you have to add zero (0) to the degree part and you have something like this N 01106.7830. Consequently, the minute part also may not be complete sometimes and you do likewise by adding zero to its digits. For Longitude there must be double spacing between the E and XXXX.XXXX (e.g. E 0738.5165). Also note that the first two X is in degree while the rest in minutes (see fig. 11)

Fig. 11.

Format for Longitude

Note: For longitude, also if the number of digits is not complete as shown in the format (fig. 11) follow the same procedure as explained for Latitude.

2.2

Implementation of Drive Test Using TEMS Before a drive test could be implemented, two things have to be put in place and they are Map configuration and Hardware configuration.

2.2.1 Map Configuration To configure Map, please follow the steps below: 1. Open the General window from the Navigator or from the menu bar click on Configuration → General and the General window will come up as shown in fig. 12 below

Fig. 12. 2.

Double-click GSM to access the Properties dialog

Fig. 13. 3.

General window

Properties dialog

Check “Use Cell Definition File” and browse to select your file. Click OK after file selection.

On loading the cell definition file, its contents are automatically displayed in the Cell Definition window. If the Cell Definition window is not open, the file will be displayed there as soon as you open the window.

Fig. 14.

Map displaying sites

Note: the sites can be enlarged by using the zoom-in

on the Map tool bar

Fig. 15.

Enlarged (zoomed) Map

The next step is to label the sites on the map so as to differentiate one site from the other. How do you label sites? Simply follow the steps below: • Click on Layer control from the Map tool bar to access the layer control dialog box. Click Add. Select and open file [in MapInfo table format (e.g. *.TAB)]

Fig. 16. • Check Automatic Labels and click OK.

Layer Control window

Fig. 17.

Labeled sites

Since the map is successfully loaded and labeled, the next step is to configure the hardware.

2.2.2 Hardware Configuration This section describes how to connect and disconnect external devices. It also explains the role of the so-called TEMS Investigation mobile. These are the connectable types of external devices: • TEMS mobile station • TEMS-specific frequency scanner (TEMS Scanner) • GPS unit • Laptop PCMCIA card with dual port cable labeled TEMS & DATA • GPS Antenna But in this chapter we shall not discuss TEMS-specific frequency scanner. Procedure

Insert the PCMCIA card with dual port cable labeled TEMS & DATA into the laptop PC card slot (See fig. 18). Of the two ports on the dual port cable, the one labeled TEMS is used to attach the mobile to TEMS Investigation. The port labeled DATA is used for data services.

Fig. 18. Hardware configuration The following should be borne in mind when attaching external devices to the PC: • The TEMS Scanner should be attached to COM1. • The DATA cable from a TEMS mobile should also ideally be attached to COM1. If you are also using a scanner so that COM1 is busy, you must connect the DATA cable in some other way. The GPS is also connected in some other way. GPS may be using COM5 with protocol NMEA 0183.

2.2.3 Enabling External Equipments (Hardware) Equipment can be enabled either from the Equipment Control toolbar or from the Port Configuration window. Enabling can be done in two ways: either for all devices at once, using the Identify Equipment function, or for each device separately. 1.

Enabling Hardware Using the Identity – You can instruct TEMS Investigation to scan all COM ports in order to detect external devices. All devices found are then enabled automatically in the application.

Click the Identify Equipment button Configuration window.

on the Equipment Control toolbar or in the Port

Fig. 19.

Port Configuration window

The window below is the Port property

Fig. 20. Use Ports:

Port properties dialog

Check the ports you want to be scanned during the identification procedure.

When you have completed the dialog, the application starts to scan the selected COM ports for external devices, automatically recognizing the type of each device: T68, NMEA 0183 etc. Ports allocated by other Windows applications are ignored, however. During the scan, the remaining equipment control functions are disabled. The detected external devices are listed in the Port Configuration window as they are identified (such a window is opened automatically if you used the button on the Equipment Control toolbar).

Fig. 21.

Port Configuration window

NOTE: If the GPS is connected it will be displayed in the Port Configuration. The GPS protocol to be used with TEMS Investigation is NMEA-0183. For TEMS mobiles, TEMS and DATA cables are detected as separate units. The detected devices are automatically enabled, but not connected; this state is indicated by a red-light symbol to the left of each device. The same equipment symbols are also shown in the main window status bar. The Identify Equipment function is “semi-automatic” in the sense that it does not automatically detect new devices that are connected physically to ports. You must click the Identify Equipment button when you want to update the list of enabled devices. 2.

Manual Enabling – Adding One Device At A Time – External equipment can also be enabled one device at a time. If you use this method, you must indicate the type of the device (e.g. “T68”, “NMEA-0183) yourself. Click the Add button on the Equipment Control toolbar or in the Port Configuration window.

Fig. 22.

Add equipment window

• Select the correct COM port for MS and GPS. For example, for the T68, choose “T68”for the TEMS cable; and for GPS choose “NMEA 0183” . The two cables will be treated as different

devices in TEMS Investigation. The TEMS cable will appear as an “MS” device as usual, whereas the DATA cable will appear as a “DC” device. The enabled device appears in the Port Configuration window. After enabling devices. The next step is to connecting external equipment 3.

Connecting External Equipment – Connecting of external devices is done as a separate step. You can however connect (and also disconnect) all devices at once. Remember that the TEMS Investigation mobile must be attached before you can connect other devices

• To connect a single external device, choose it in the combo box of the Equipment Control toolbar, then Click Connect on the Equipment Control toolbar. • To connect all external devices, Click Connect All on the Connections toolbar. Connected devices are accompanied by a green-light symbol in the combo box. The same symbol appears in the status bar and in the Port Configuration window. When all external devices are successfully connected, you can now implement the drive test.

2.2.4 Drive Test Implementation Proper After enabling and connecting external equipments, you can now perform drive test by recording log files. You can also replay saved log files. Logfiles can be recorded in the following ways in TEMS Investigation: • From the Record toolbar or Logfile menu Click Start Recording on the Record toolbar. You are asked to name the logfile when you click . The default naming format is MMDD_nn.log, where MM is the current month, DD is the current day of the month, and nn is an incrementing counter starting at 01. After naming the logfile, you commence drive test immediately until you have covered all the sites required of you. And from the laptop you can see the path of the drive test. For example see fig. 23

Fig. 23.

Example of drive test path

While on drive test you can also perform the following: To pause the recording without closing the logfile, click Pause Recording. Click the button once more to resume the recording. Special events indicating pausing and resumption are written to the logfile. Click Stop Recording to end the recording and close the logfile. Once you have closed it, you cannot log any more data to the same file. At any time while recording, you can close the current logfile immediately and continue recording to a new file. Click Swap Logfiles. The new logfile will be named according to the default format MMDD_nn.log, regardless of the name you chose for the original file. To begin drive test click on and you will be prompted to name the logfile and after renaming the logfile the computer starts recording.

Note: Sometimes you may think that you have successfully recorded the logfiles while performing drive test but to no avail. There are two ways to know whether logfiles are properly recorded or not. One way is that once you click on the Record button , it will change to the Stop button and secondly, from the right-top of the task bar, you see files counting in numbers. These two ways signifies recording.

3

DRIVE TEST ANALYSIS USING TEMS AND MAPINFO

3.1

Analyze by TEMS Replay Replaying Logfiles

After drive test you can replay logfiles. By replaying a logfile, you can view and analyze problems like Interference, missing neighbors, call drop, handover and coverage repeatedly. Note: To be able to replay a logfile, you must disconnect your external equipment. Logfile replay is controlled from the Replay toolbar or from the Logfile menu. The quickest method is to use the toolbar buttons: Open/Close Logfile - Open a logfile/Close the logfile that is currently open. Only one logfile can be opened at a time. Rewind Logfile - Rewind the logfile to the beginning. Play/Stop Logfile - Replay the logfile/Stop logfile replay. The speed of the replay is variable and is set from the Logfile menu. When the stop button is clicked to halt fast forwarding, all presentation windows are updated. Step Logfile - Advance one step in the logfile, i.e. read one more mobile station report. Note that a presentation window is not always updated when advancing a single step or just a few steps. Fast-forward Logfile - Play the logfile at high speed. No updating of presentation windows takes place until the replay is stopped. Find in Logfile - Search forward in the logfile for a time instant, a type of event, or a type of message

3.1.1 Interference Problem Analysis Interference could be as a result of geographical environment (e.g. hill, mountains, high building etc), external source (e.g. radar), frequency multiplexing which brings forth co-channel and

adjacent interference (also know as internal interference of the system), multi-path effect and external factors of the network (e.g. interference of repeaters) There might be interferences in both uplinks and downlinks. Uplink interference can be positioned with the numbers of interference bands and Call Drop rates in HUAWEI OMC traffic statistics terminal. Interference band is an indication of idle TCH levels of 5 grades in all. Interference Band 1~5 Generally, shall idle channel fall into Interference Band 4 and Interference Band 5 continuously, it can be determined that there exists interference. Beside, measurement report for uplink and downlink can be viewed from Signaling Analyzer MA-10 connected to ABIS interface. In this way, uplink interference and downlink interference can also be positioned. When the receive level is good but the quality is bad this shows that there is interference. And if the receivel is bad and quality good does not necessarily mean interference. The figure below depict downlink interference problem, these can be seen from the Line Chart (see Fig. 24)

Fig. 24.

Line Chart showing interference

3.1.2 Missing Neighbor Problem Analysis Sometimes a site will not add its neighbor and as a result of this, there will be call drop as shown in the fig below. ASH000 omits the neighbor with ASH001

Fig. 25. window displaying This can also be confirmed from the signaling message as shown below:

Fig. 26.

signaling message

3.1.3 Call Drop Problem Analysis Under drive test, call drop problem analysis cannot be easily identified, because it will also require result from Traffic Statistics.

3.1.4 Handover Problem Analysis So also for handover problems, analysis cannot be concluded from drive test only, it will require result from Traffic Statistics.

3.1.5 Coverage Problem Analysis Major factors affecting coverage are the following: i. Blind zone for signals as a result of no overlapping between coverage areas of two base stations or no overlapping caused by obstructions and ii. Cross coverage cell as signals emitted from high base stations can be transmitted on hilly landforms or along roads to places far way. This will result as a lonely island and when a call is connected into the “island” of a base station, which is far from the base station, configuration handover in this cell may immediately result in Call Drop once the mobile station leaves this “island” area.

Fig. 27.

3.2

Displaying coverage problem

Analyze by TEMS Export You export logfiles after drive test, so as to analyze information derived. Logfiles can be exported in the following formats: • Text file with tab delimited data (suitable for processing in, for example, a spreadsheet application). TEMS Automatic logfiles, too, can be exported in this format. • MapInfo, Interchange file or Tab file • ArcView shape file • Marconi Planet file

But we shall only be using MapInfo Tab file format since we shall be using MapInfo to analyze data. Preparing an Export Order • First, if the logfile is currently open, close it. While a logfile is open it cannot be exported. • From the Logfile menu, choose Export Logfile.

Fig. 28.

Export Logfile window

Click Add. The Add Export Order dialog appears:

Fig. 29.

Add Export Order dialog

First select Format Format

Select the output format for your logfiles (Select MapInfo Tab file). Then click Setup to specify details of the export;

Input files

Enter the name of the logfiles you want to export, or click “Browse file” and select the files. It is possible to export all logfiles in a directory by typing “*.log”.

On clicking the Setup button, a dialog appears as shown below. The Information Elements tab, however, is common to all formats:

3. Fig. 30.

MapInfo Tab-file setup

Here you select which information elements. • To export an element, select it in the Available IEs list and click the “>” button. The information elements may include the following: All-ARFCN BCCH All-Cell Name All-LAC All-RxLev Full All-RxLev Full (dBm) All-RxLev Sub *All-RxLev Sub (dBm) All-RxQual Full All-RxQual Full (%) All-RxQual Sub All-RxQual Sub (%) Note: the information elements may not necessarily include the above. It depends on what you want to do. From the MapInfo Tab-file setup dialog window you also have the “Options tab” click the option tab and check “Don not export events”.

Saving and Loading Export setups When you are done specifying the export, you may want to save the setup for future use. • Click Save and store the file where appropriate. It will have extension .tex. • To load a previously saved setup in the Setup dialog, click Load and locate the .tex file. Click OK after selection. Input files by browsing files

Fig. 31.

Add Export Order dialog

Click OK after inputting files So you add several export order one by one depending on the number of log files as shown in the Export Logfile window below

Fig. 32.

Export Logfile window displaying Added files

Executing the Export Orders All the export orders you have defined are listed in the Export Logfile window. Click Start to execute the export orders. Click Abort to stop the execution.

Fig. 33.

Export Logfile window displaying successful added files

After execution of the export orders is successful you will see the Export Result as shown below

Fig. 34.

3.3

Export Result window

Analyze by Generating Report

From one or several logfiles you can generate a report in HTML format which summarizes the data in the logfiles. When the report is ready it will be opened in the default web browser. To prepare a logfile report, click Generate Report on the Report toolbar or from the menu bar, click Logfile → Report Generator A wizard interface appears. After finishing each step, click Next to proceed to the next one. Step 1: Logfiles In this step you choose the logfile or logfiles on which to base the report. • Click the Add button to open a file dialog. • Select the desired file or files.

Fig. 35.

Report Wizard Logfiles window

Step 2: Threshold Values In this step you compare information element values with thresholds. All information elements listed will also have their distributions visualized in bar charts.

Fig. 36.

Report Wizard Thresholds window

A number of thresholds are predefined in the dialog; you can also define your own thresholds. Check those that you wish to use, and uncheck the others. Each item in the list represents a set of two thresholds for an information element value: Whether peaks or dips are counted depends on the information element and cannot be changed. To see which is counted for a particular element, select a threshold pair containing it in the list and click Edit (see screenshot below). In the report, it is indicated for each threshold • How many times the value of the information element has crossed the threshold (changed from a more normal value to a more extreme one) • How long these peaks/dips have lasted on average. Adding User-defined Thresholds You can also define thresholds of your own: • To add a pair of thresholds, click the Add button.

Fig. 37. Add Threshold window • Choose an information element. • Choose an argument (where applicable). • Specify the two thresholds. • Click Add to add this threshold pair to the list and keep the Add Threshold dialog open. • Click OK to add this threshold pair to the list and close the Add Threshold dialog. Editing Thresholds • To edit the properties of a threshold pair, select it and click the Edit button. A dialog similar to the Add Threshold dialog appears. Make the desired changes. Deleting Thresholds • To delete a threshold pair, select it and click the Delete button. Step 3: Events The report has a section with event statistics. In this step you choose what event types to include in these statistics. • Check the events you want to include, and uncheck the rest.

Fig. 38.

Report Wizard Events

Step 4: Devices • Check the external devices whose data you want to include in the report. By default all devices used to record the logfile will be checked. GPS data, if available, is included implicitly.

Fig. 39.

Report Wizard Devices

Step 5: Scanned Channels In this step you choose which of your scanned channels you want to present in the report. And if there is no scanned channels click on Next. The number within square brackets is the frequency band.

Fig. 40.

Report Wizard Events Scanned Channels

• Move the channels you wish to present from the Available box to the Selected box. For each selected channel, the report will contain RxLev statistics (mean, median, min, max) and an RxLev bar chart. The averaging takes place in the mW domain.

Step 6: Output Directory • Specify the output directory for the report files if not specified.

Fig. 41.

Report Wizard Output Directory

Click on Finish after specifying the output directory for the report files The logfiles will be processed as shown below

Fig. 42. After processing, the Result as shown below

Progress status bar

Fig. 43.

Generated report results

Report Contents The logfile report has the following main sections • Header: Date, time • Logfile information: Logfile names and used equipment • Worst cell indication: Ranking of cells based on thresholds crossed and events triggered • Thresholds: Detailed statistics on how often and in what cells each threshold has been crossed • Events: Statistics on events • Scan data: Statistics on the signal strength of scanned channels. • Distribution charts for threshold parameters • Distribution charts for scan data

3.3

Analyze Using MapInfo

To open MapInfo Professional 6.5 Choose Start > Programs > MapInfo > MapInfo Professional 6.5 or click on the shortcut on the desktop if one is created. To analyze drive test data using MapInfo, you will need an input data and this input data is the TEMS exported logfiles. If you have not exported logfiles, check the previous pages on how to export log files using TEMS Investigation GSM 4.0. MapInfo can be used to analyze RX_LEV and RX_QUAL as we shall see in the following sections.

3.3.1 Show RxLev Map by MapInfo To show RxLev Map, a Thematic Map needs to be created.

To create a Thematic Map simply following the steps below: Step 1: In this step click on Open Table on the toolbar or menu bar and the Open Table dialogue box comes up

Fig. 44. File name Files of type Preferred View

Open Table window

Select file name where saved Select “MapInfo (*.tab)” Change from “Automatic” to “Current Mapper”

After selection click Open The result (map path) will be displayed as shown below

Fig. 45.

Map path not zoomed

Note: The Fig. above shows the map path of the drive test which need to be enlarged To enlarge, simply click zoom-in

on the Map tool bar

Fig. 46.

Zoomed map path

Creating Thematic Map To create Thematic Map, from menu bar choose Map > Create Thematic Map. The Create Thematic Map - Step 1 of 3 dialog displays. Creating a thematic map is a three-step process: Step 1: Choosing A Type Of Thematic Map Thematic templates allow you to make a thematic map based on values and settings in our default types, alter these settings and/or save them as a new template you can use again. When you first create a thematic map, you begin by selecting a template that you can modify to suit your requirements. You cannot create a theme without using an existing theme template. To create a thematic map you can only use the “Ranges” under “Type” (see fig. 47)

Fig. 47. Type: Template Name:

Step 1 of creating thematic map

Select Ranges Select Template Name (e.g. Region Ranges, Solid Yellow-Blue, Dark

Click on Next Step 2: Select a Table and a Field

Fig. 48.

Step 2 of creating thematic map

Table: Field:

Select a table (these tables are logfiles) Select a field (specify what you want to analyze e.g. RXLEV_FULL)

Click Next Step 3: Customizing Your Thematic Map

Fig. 49.

Step 3 of creating thematic map

The last step allows you to customize your thematic map, or create the map based on the default settings. You can also preview the map's legend before you display the map, and change the legend's label order.

Preview Displays a sample legend of the thematic map you are creating. Legend label Order Ascending and Descending determines the order in which range and value labels (for ranged and individual values maps) and field labels (for all other thematic maps) appear in the legend. If you are creating a ranged map, the order you specify is also shown in the Customize Range Styles dialog. 1. Choose Ascending to display ranges from lowest to highest value. 2. Choose Descending to display ranges from highest to lowest value.

Customize

The buttons in the Customize group enable you to change the default settings of particular aspects of your thematic map Ranges - Allows you to customize settings on a ranged map. This option is available for ranged and grid maps.

Fig. 50.

Customize Ranges window

Method: Select ‘Custom’ # of Ranges: Select ‘4’ to define the ranges for RXLEV_FULL or Select ‘3’ to define the ranges for RXQUAL_FULL Define the minimum (>=Min) and maximum (