Skip to main content

imp002 RF Certification Step By Step

Performing RF Certification Testing On Your imp002 Design

The imp002 is now no longer in production

The imp002 comes pre-certified for wireless regulatory compliance in many regions. However, in other regions, it is necessary to perform certification testing by demonstrating worst-case radio performance with the imp002 installed in your final design (on your PCBA and in your mechanical enclosure). This guide provides a list of the steps needed to prepare a unit for test, as well as a guide to using the tools provided to run the necessary tests.

1. Choose a Lab to Perform your RF Certification

You can choose to engage a lab directly to obtain RF certifications for your product, or if your contract manufacturer has existing relationships with labs, it may be more cost effective to ask them to perform the RF certification for you. If you choose to engage a lab directly, keep in mind that the testing process will be simpler and faster if the lab is within easy travel distance and you can easily communicate with your lab. Prices differ for every country’s RF certification, so be sure to obtain the necessary quotes before testing begins.

2. Obtain an RF Test Kit

RF Certification testing is not performed with ordinary production imp002 modules. Instead, you will install an imp002 test unit (part number ‘imp002-test’) pre-loaded with RF Test software onto your PCBA for testing. The RF Test software allows the radio to be configured with a set of simple serial commands, sent over an FTDI USB-to-Serial cable. Contact sales@electricimp.com to purchase an RF Test Kit. The Kit includes the imp002-test, which is loaded with RF Test software, and an FTDI TTL-232R-3V3-WE cable.

3. Set up Hardware for Test

To perform RF Testing, a PC will use a Windows command-line tool to send commands to the imp002-test. Commands are sent to the imp002-test over serial, so you will need to connect the imp002-test to the FTDI USB-to-Serial cable. Solder the imp002-test onto your product PCBA, then make the following modifications to your PCBA:

  1. Cut PCB traces between product circuitry and the imp002-test’s pins 19 and 21
  2. Solder the FTDI cable Black wire (Ground) to GND
  3. Solder the FTDI cable Yellow wire (RXD) to pin 19
  4. Solder the FTDI cable Orange wire (TXD) to pin 21
  5. Leave the FTDI cable’s Brown (CTS_L), Red (VCC), and Green (RTS_L) wires unconnected


Connecting the FTDI cable to your Device Under Test (DUT)
Note: for conducted tests, you will need coax cable Murata part number MXHQ87WA3000, available from Mouser.
The MXHQ87WA3000 will connect to the coax connector on the imp002-test

4. Obtain Required Software

  1. Download the FTDI Virtual COM Port driver.
  2. Download the the WL.EXE test software and batch files. This is the command-line tool that will be run on the PC to control the Device Under Test

  3. With the FTDI Virtual COM Port driver installed and the FTDI cable plugged into your PC, open the Device Manager and determine the COM Port number of the FTDI cable. Note the COM Port number for use with the WL.EXE test tool.

5. Run the WL.EXE Test Tool

The WL.EXE tool is a command-line utility. In windows, open a command prompt and navigate to the directory where you’ve stored the WL.EXE tool.

C:\Users\tester> cd Downloads\imp002-rftest

To place the RF Test imp into a specific mode, execute the appropriate batch file from the Windows command line. Each batch file takes one or two parameters:

  1. The COM port number of the FTDI USB-to-Serial cable
  2. The channel for the imp002-test to broadcast/receive on

In the following examples, the FTDI USB-to-Serial cable is COM Port 29:

Turn radio off:

down.bat 29

Transmit on channel 1 at maximum power, 1Mbps 802.11b CCK:

tx­11b­1m.bat 29 1

Transmit on channel 13 at maximum power, 1Mbps 802.11b CCK:

tx­11b­1m.bat 29 13

Transmit on channel 1 at maximum power, 6Mbps 802.11g OFDM (maximum OFDM power):

tx­11g­6m.bat 29 1

Transmit on channel 1 at maximum power, 54Mbps 802.11g OFDM (maximum OFDM complexity):

tx­11g­54m.bat 29 1

Transmit on channel 1 at maximum power, 6.5Mbps 802.11n 20MHz (MCS0):

tx­11n­mcs0.bat 29 1

Transmit on channel 1 at maximum power, 65Mbps 802.11n 20MHz (MCS7):

tx­11n­mcs7.bat 29 1

Transmit carrier only:

tx­carrier.bat 29 1

Put the imp002-test in RX mode:

rx.bat 29 1

These commands simulate the maximum duty cycle that an imp002 can produce. If you have other requirements to complete your RF Certification testing, please contact support@electricimp.com.