Microwave 4 Click

Microwave 4 Click is a compact add-on board that utilizes the Doppler Shift Phenomenon to sense motion. This board features the PD-V12, a miniature high-frequency microwave transceiver from Ningbo Pdlux Electronic Technology. The transmitter on this transceiver works on a 24.1GHz frequency over the flat Plane antenna.

Click Product page

Click library

• Author : Stefan Ilic
• Date : Jun 2023.
• Type : ADC/I2C type

Software Support

We provide a library for the Microwave 4 Click as well as a demo application (example), developed using MikroElektronika compilers. The demo can run on all the main MikroElektronika development boards.

Package can be downloaded/installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Library Description

This library contains API for Microwave 4 Click driver.

Standard key functions :

• microwave4_cfg_setup Config Object Initialization function.

  void microwave4_cfg_setup ( microwave4_cfg_t *cfg );

• microwave4_init Initialization function.

  err_t microwave4_init ( microwave4_t *ctx, microwave4_cfg_t *cfg );

Example key functions :

• microwave4_read_raw_adc Microwave 4 read raw ADC value function.

  err_t microwave4_read_raw_adc ( microwave4_t *ctx, uint16_t *raw_adc );

• microwave4_read_voltage Microwave 4 read voltage level function.

  err_t microwave4_read_voltage ( microwave4_t *ctx, float *voltage );

• microwave4_set_vref Microwave 4 set vref function.

  err_t microwave4_set_vref ( microwave4_t *ctx, float vref );

Example Description

This example demonstrates the use of the Microwave 4 Click board™ by reading and displaying the results of AD conversion and motion detection.

The demo application is composed of two sections :

Application Init

The initialization of I2C or ADC module and log UART. After driver initialization, the app calculates the reference ADC value.

void application_init ( void )
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    microwave4_cfg_t microwave4_cfg;  /**< Click config object. */

    /** 
     * Logger initialization.
     * Default baud rate: 115200
     * Default log level: LOG_LEVEL_DEBUG
     * @note If USB_UART_RX and USB_UART_TX 
     * are defined as HAL_PIN_NC, you will 
     * need to define them manually for log to work. 
     * See @b LOG_MAP_USB_UART macro definition for detailed explanation.
     */
    LOG_MAP_USB_UART( log_cfg );
    log_init( &logger, &log_cfg );
    log_info( &logger, " Application Init " );

    // Click initialization.
    microwave4_cfg_setup( &microwave4_cfg );
    MICROWAVE4_MAP_MIKROBUS( microwave4_cfg, MIKROBUS_1 );
    err_t init_flag = microwave4_init( &microwave4, &microwave4_cfg );
    if ( ( ADC_ERROR == init_flag ) || ( I2C_MASTER_ERROR == init_flag ) )
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }

    log_printf( &logger, " Calibrating the sensor...\r\n" );
    log_printf( &logger, " There must be no movement near the sensor!\r\n" );
    log_printf( &logger, "----------------------------------\r\n" );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );

    if ( MICROWAVE4_OK == microwave4_read_voltage( &microwave4, &reference ) )
    {
        log_printf( &logger, " The sensor has been calibrated!\r\n" );
        log_printf( &logger, "  Detector AN Voltage : %.3f[V]\r\n", reference );
        log_printf( &logger, "----------------------------------\r\n" );
        Delay_ms ( 100 );
    }
    else
    {
        log_error( &logger, " Communication error." );
        for ( ; ; );
    }

    log_printf( &logger, "The motion detector unit is ready.\r\n" );
    log_printf( &logger, "----------------------------------\r\n" );
    Delay_ms ( 100 );

    log_info( &logger, " Application Task " );
}

Application Task

The demo application reads the ADC results, takes an ADC sample, compares the difference between the taken samples and the ADC reference value, and reports the movement if the difference is higher/lower than the selected threshold value. Results are being sent to the UART Terminal, where you can track their changes.

void application_task ( void ) 
{
    if ( MICROWAVE4_OK == microwave4_read_voltage( &microwave4, &voltage ) )
    {
        if ( ( ( voltage + MICROWAVE4_THRESHOLD ) < reference ) || 
             ( ( voltage - MICROWAVE4_THRESHOLD ) > reference ) )
        {
            if ( MICROWAVE4_FLAG_SET == flag )
            {
                log_printf( &logger, " Motion detected!\r\n" );
                log_printf( &logger, " Detector AN Voltage : %.3f[V]\r\n", voltage );
                log_printf( &logger, "----------------------------------\r\n" );
                flag = MICROWAVE4_FLAG_CLEAR;
                Delay_ms ( 100 );
            }
        }
        else
        {
            flag = MICROWAVE4_FLAG_SET;
        }
    }
}

The full application code, and ready to use projects can be installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Other Mikroe Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.Microwave4

Additional notes and informations

Depending on the development board you are using, you may need USB UART Click, USB UART 2 Click or RS232 Click to connect to your PC, for development systems with no UART to USB interface available on the board. UART terminal is available in all MikroElektronika compilers.