Multi-Antenna Channel Sounding

When setting the following channel sounding parameters with bt_le_cs_set_procedure_parameters I am getting E: Failed to set procedure parameters (err -22) or BT_HCI_ERR_INVALID_PARAM when printing the opcode strings. this only happens for any configuration where B>1 (i.e., the reflector having multiple antennas) while A1 and A2 work just fine. Does this indicated that my controller (nordic libsoftdevicecontroller) does not support multiple antennas for the reflector or is it possible that it fails after reading the remote capabilities (i.e., that i return the number of antennas and paths on the reflector)?

const struct bt_le_cs_set_procedure_parameters_param procedure_params = {
.config_id = CS_CONFIG_ID,
.max_procedure_len = 1000,
.min_procedure_interval = 10,
.max_procedure_interval = 10,
.max_procedure_count = 0,
.min_subevent_len = 60000,
.max_subevent_len = 60000,
.tone_antenna_config_selection = BT_LE_CS_TONE_ANTENNA_CONFIGURATION_A2_B2,
.phy = BT_LE_CS_PROCEDURE_PHY_1M,
.tx_power_delta = 0x80,
.preferred_peer_antenna = BT_LE_CS_PROCEDURE_PREFERRED_PEER_ANTENNA_1,
.snr_control_initiator = BT_LE_CS_SNR_CONTROL_NOT_USED,
.snr_control_reflector = BT_LE_CS_SNR_CONTROL_NOT_USED,
};


Zepyhr version is v4.0.99-e48bca44dd59 i.e, nrf connect sdk version 3.0.0-rc1

Both prj.conf have 

CONFIG_BT_RAS_MAX_ANTENNA_PATHS=4
CONFIG_BT_CTLR_SDC_CS_MAX_ANTENNA_PATHS=4
CONFIG_BT_CTLR_SDC_CS_NUM_ANTENNAS=2
To support up to A2B2
Parents
  • according to Bluetooth Core Specification, there is a requirement related to Preferred_Peer_Antenna field:

    ```

    The Preferred_Peer_Antenna parameter indicates the preferred peer-ordered antenna
    elements to be used by the remote device for the antenna configuration denoted by
    the Tone_Antenna_Config_Selection parameter. The number of bits set in this field
    shall be greater than or equal to the number of antenna elements denoted by the
    Tone_Antenna_Config_Selection parameter.

    ```

    Can you try to set 2 bits in procedure_params.preferred_peer_antenna and check if it helps?

Reply
  • according to Bluetooth Core Specification, there is a requirement related to Preferred_Peer_Antenna field:

    ```

    The Preferred_Peer_Antenna parameter indicates the preferred peer-ordered antenna
    elements to be used by the remote device for the antenna configuration denoted by
    the Tone_Antenna_Config_Selection parameter. The number of bits set in this field
    shall be greater than or equal to the number of antenna elements denoted by the
    Tone_Antenna_Config_Selection parameter.

    ```

    Can you try to set 2 bits in procedure_params.preferred_peer_antenna and check if it helps?

Children
Related