Example Code

On-Off Keying Modulator

Code and Documents


On-Off Keying (OOK) is a digital modulation scheme in which the presence of a carrier wave indicates the transmission of bit '1', while the absence of a carrier wave is used for transmission of the bit '0'. OOK modulation scheme is used commonly to transmit Morse code over radio frequencies. It has also been used in ISM bands to transfer data between computers. There have also been instances of OOK being used in optical communications.

This example performs OOK modulation using the NI 5640R IF Transceiver.

The details of the example are as follows:

1. The modulator operates at two samples per symbol.

2. Supported symbol rates are 97.65625 kHz, 197.3125 kHz, 390.625 kHz, 781.25 kHz, 1.5625 MHz, 3.125 MHz, 6.25 MHz and 12.5 MHz.

Note that not all symbol rates can be generated without an external clock on the NI 5640R.

3. Device Utilization Summary:

Number of BUFGMUXs 6 out of 16 37%

Number of External IOBs 403 out of 556 72%

Number of RAMB16s 33 out of 136 24%

Number of SLICEs 2185 out of 13696 15%

4. Clock Rates:

Base clock: Configuration_Clk

Requested Rate: 20.000000MHz

Theoretical Maximum: 58.099001MHz

Base clock: RTSI_Ref_Clk

Requested Rate: 50.005001MHz

Theoretical Maximum:63.21125MHz

Base clock: DAC_0_IQ_Clk

Requested Rate: 50.005001MHz

Theoretical Maximum: 103.508954MHz

Example code from the Example Code Exchange in the NI Community is licensed with the MIT license.



      I have just downloaded the example,but there are some problems when I open the host VI. It can not find _ni5640R rioWrite32.vi  and _ni5640R rioRead32.vi .