6.RF & Radio

This section describes the RF & Radio-related Frequently Asked Questions.

6.1.What is the Intermediate Frequency (IF) of the Radio?

TheIntermediate Frequency (IF)of the radio is 1 MHz. See application noteBluetooth® Direct Test Modethat describes the required RF parameters for certification documents and how to setup the RF testing modes for the DA14531 Bluetooth® Low Energy SoC.

6.2.What does the Local Oscillator (LO) Frequency Does the Radio Usage?

The Local Oscillator (LO) frequency is:(2 x Carrier Frequency) + 1 MHz.

看到应用注释Bluetooth® Direct Test Modethat describes the required RF parameters for certification documents and how to setup the RF testing modes for the DA14531 Bluetooth® Low Energy SoC.

6.3。通信范围can be Achieved with the DA14531?

TheBluetooth® SIGhas published a range estimator on their website that can be used to calculate the effective, reliable range between Bluetooth® devices:https://www.bluetooth.com/bluetooth-technology/range/

6.4.Is a Pi Filter on the RFIOp Port Required?

Yes, to meet the product specification for ETSI, FCC and ARIB - a Pi Filter is needed to remove the out of band emission. Also, the extra Pi Filter for the RF circuit is needed to avoid Spurious Emissions Reduction. For more information on the antenna filters, see application noteDesigning Printed Antennas for Bluetooth® Smart.

TheDXF filesare available too.

6.5.Is 2 Mb/sec Data Throughput Supported?

No. DA14531 is fully compliant with Bluetooth® Low Energy 5.1 standard, where 2 Mb/s PHY support is optional. So, DA14531 supports up to 1 Mb/s.

6.6.Can I Change the Tx Power Level Using the Production Test Firmware?

TheProduction Testfirmware that comes along with the SDK6.0.14 supports a configurable TX level. The project is located underthe projects\target_apps\prod_testSDK path. The TX level can be changed by sending an appropriate command via UART (HCI_SET_TX_POWER_CMD_OPCODE). In addition, the commands can be sent either with two-wire UART over P00/P01 or single-wire UART over P03 or P05.

The available commands and responses are shown inFigure 9andFigure 10:

_images/tx_command.png

Figure 9Tx Power Command

_images/tx_response.png

Figure 10Tx Power Response

For this demonstration, single-wire UART is used over P05 to set the tx power at -18 dBm.

  1. Prepare the DA145xx Pro Development kit for single-wire UART applied on P05 (seeFigure 11). Install thethree (3)Jumpers in HeaderJ1in the positions indicated by the blue rectangles inFigure 11. See alsoFigure 27inGetting Started with the Pro Development Kit (HTML)document.

_images/1_wire_uart.png

Figure 11Configuration of DA145xx Pro DK for Single-Wire UART Applied on P05

  1. Open theprod_testKeil project and navigate touser_periph_setup.h. Configure the GPIOs for UART_TX / UART_RX for single-wire UART as shown inFigure 12.

_images/user_periph_setup.png

Figure 12Configuration of user_periph_setup.h for Single-Wire UART Applied on P05

  1. Build and run the prod_test.

  2. To set the tx power at -18 dBm, enter the following characters01 1B FE 01 01over UART.

  • 0x01 -> every command starts with a 0x01

  • 0x1B 0xFE -> the op code of the sleep command 0xFE1B

  • 0x01 -> parameter length

  • 0x01 -> set the tx power at -18 dBm

6.7.Is Any Calibration of the RF Parameters Required in Production?

No, this is not required. Dialog Bluetooth® Low Energy devices are calibrated when the IC is manufactured. The accuracy of the 32MHz clock is essential for the quality of the RF. So, based on the application and the selected 32MHz xtal this might need trimming at application level. TheDialog Production Line Tool (PLT)supports XTAL trimming for 16 devices in parallel.