Having very short range with custom board

[Tai]

Hello everyone,

I got an issue with the custom board nRF52832 (Raytac BLE module) as I only achieve very short distance between the BLE device and Android app without data loss. This distance is about 50 cm. The RSSI I noticed is below -70dBm.

With same code, it perfectly ran on nRF52 DK and the range I tested without data loss is about 5 meters. 

I tried to increase TX power as the following code ( using sd_ble_gap_tx_power_set()). However, it didn't improve much. Is there any suggestion in this case?

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static void advertising_init(void)

{

uint32_t err_code;

ble_advdata_t advdata;

ble_advdata_t scanrsp;

ble_adv_modes_config_t options;

int8_t tx_power_level = 4;

// Build advertising data struct to pass into @ref ble_advertising_init.

memset(&advdata, 0, sizeof(advdata));

advdata.name_type = BLE_ADVDATA_FULL_NAME;

advdata.include_appearance = false;

advdata.flags = BLE_GAP_ADV_FLAGS_LE_ONLY_LIMITED_DISC_MODE;

advdata.p_tx_power_level = &tx_power_level;

sd_ble_gap_tx_power_set(tx_power_level);

memset(&scanrsp, 0, sizeof(scanrsp));

scanrsp.uuids_complete.uuid_cnt = sizeof(m_adv_uuids) / sizeof(m_adv_uuids[0]);

scanrsp.uuids_complete.p_uuids = m_adv_uuids;

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

static void advertising_init(void)
{
    uint32_t               err_code;
    ble_advdata_t          advdata;
    ble_advdata_t          scanrsp;
    ble_adv_modes_config_t options;
		int8_t tx_power_level = 4;

    // Build advertising data struct to pass into @ref ble_advertising_init.
    memset(&advdata, 0, sizeof(advdata));
    advdata.name_type          = BLE_ADVDATA_FULL_NAME;
    advdata.include_appearance = false;
    advdata.flags              = BLE_GAP_ADV_FLAGS_LE_ONLY_LIMITED_DISC_MODE;
		advdata.p_tx_power_level   = &tx_power_level;
			
		sd_ble_gap_tx_power_set(tx_power_level);
	
    memset(&scanrsp, 0, sizeof(scanrsp));
    scanrsp.uuids_complete.uuid_cnt = sizeof(m_adv_uuids) / sizeof(m_adv_uuids[0]);
    scanrsp.uuids_complete.p_uuids  = m_adv_uuids;

    memset(&options, 0, sizeof(options));
    options.ble_adv_fast_enabled  = true;
    options.ble_adv_fast_interval = APP_ADV_INTERVAL;
    options.ble_adv_fast_timeout  = APP_ADV_TIMEOUT_IN_SECONDS;

    err_code = ble_advertising_init(&advdata, &scanrsp, &options, on_adv_evt, NULL);
    APP_ERROR_CHECK(err_code);

    ble_advertising_conn_cfg_tag_set(CONN_CFG_TAG);
}

Thanks!