Channel Sounding: Reflector with Ranging Responder

Overview

Application demonstrates the BLE responser role in an RAP (Ranging Profile) system and the reflector role for Channel Sounding. It can be connected with a BLE requester application (Refer to ras_rreq_initiator). And then indicates channel sounding ranging procedure or sends ranging procedure data according GATT Ranging service control point write commands.

Requirements

  1. Atmosic EVK <board | serial>

Note

  • Currently, only the ATM34/e series of Atmosic devices are supported.

  1. Button

    • Press Button2 to unpair the device.

    Note

    • The default pin for Button2 is P6.

    • Install the JP27 and JP25 jumpers to enable Button2.

  2. Antenna_switch: connect IO to switch antenna as channel sounding enable

  • Need to connect external antenna switch board for EVK

  • For the related pin setting, please refer to the overlay file.

  • If there is no overlay file, the function is disabled.

  • Refer to atmosic,antenna.yaml for below properties.

    • e.g. P5 as antenna switch (JP29 in EVK board).

      In the case, Button1 can not be used, since it is also used with P5.

    / {
 aliases {
  sw0 = &button1;
 };
};
&atm_antenna {
 ant-out5-pin = <5>;
 mdm-ant-rx-3to0 = <0x00002000>;
 mdm-ant-tx-3to0 = <0x00002000>;
 mdm-ant-idle =<0>;
 status = "okay";
};

    • e.g. P16 as antenna switch, and antenna0 with P16 high

    &atm_antenna {
 ant-out0-pin = <16>;
 mdm-ant-rx-3to0 = <0x00000001>;
 mdm-ant-tx-3to0 = <0x00000001>;
 mdm-ant-idle =<0x01>;
 status = "okay";
};

Configuration Options

CS Enhancement 1 (IPT) Support

To enable CS (Channel Sounding) Enhancement 1 support, which allows the reflector to advertise Inline PCT (Phase Correction Term / IPT) capability to the initiator, add the following configuration option to your project configuration file (prj.conf):

CONFIG_ATM_ENA_LL_FEAT_CS_ENH1=y

This option enables CS Enhancement 1 (IPT) at the link layer, allowing the initiator to detect and activate IPT in the CS configuration when both sides support it.

Filter Ranging Data

To enable filtering of ranging data reported by the RAS server, add the following configuration option to your project configuration file (prj.conf):

CONFIG_RAS_FILTER_RD=y

This option enables:

  • Support for the RAS Set Filter control point command

  • Filtering of Mode 2 ranging data fields, including:

    • Antenna Permutation Index (bit 0)

    • Phase Correction Term (bit 1)

    • Quality Indicator and Extension Indicator (bit 2)

Note

CONFIG_RAS_FILTER_RD=y is typically paired with CONFIG_ATM_ENA_LL_FEAT_CS_ENH1=y when using CS reflector IPT, so that the initiator can request filtering of the Phase Correction Term from the ranging data:

CONFIG_ATM_ENA_LL_FEAT_CS_ENH1=y
CONFIG_RAS_FILTER_RD=y

Building and Running

This application is built from openair/applications/ras_rrsp_reflector.

Build command:

west build -p always -b <BOARD> openair/applications/ras_rrsp_reflector --sysbuild -T applications.ras_rrsp_reflector.atm

Build with MCUboot command: Run the following command to build the MCUboot and application

west build -p always -b <BOARD>@mcuboot openair/applications/ras_rrsp_reflector --sysbuild -T applications.ras_rrsp_reflector.atm.mcuboot

Build with OTA command: Run the following command to build the application and MCUboot with -DEXTRA_CONF_FILE="basic_ota_bt.conf" to enable OTA function

west build -p always -b <BOARD>@mcuboot openair/applications/ras_rrsp_reflector --sysbuild -T applications.ras_rrsp_reflector.atm.mcuboot.ota

Flash command:

west flash --no-rebuild --device <DEVICE_ID> --jlink --fast_load [--erase_all]