nRF51822和nRF52832 广播功率设置
1、nRF51822 广播包的设置（SDK12.3.0）：
/**@brief Set the radio's transmit power.
*
* @param[in] tx_power Radio transmit power in dBm (accepted values are -40, -30, -20, -16, -12, -8, -4, 0, and 4 dBm).
*
* @note The -30dBm setting is only available on nRF51 series ICs.
* @note The -40dBm setting is only available on nRF52 series ICs.
*
* @retval ::NRF_SUCCESS Successfully changed the transmit power.
* @retval ::NRF_ERROR_INVALID_PARAM Invalid parameter(s) supplied.
*/
SVCALL(SD_BLE_GAP_TX_POWER_SET, uint32_t, sd_ble_gap_tx_power_set(int8_t tx_power));
1.1、在需要设置的地方加上sd_ble_gap_tx_power_set(int8_t tx_power)； tx_power形参的值分别：-30, -20, -16, -12, -8, -4, 0, and 4 dBm，值越大信号越强。
2、nRF52832 广播包的设置（SDK15.0.0）：
/**@brief Set the radio's transmit power.
*
* @param[in] role The role to set the transmit power for, see @ref BLE_GAP_TX_POWER_ROLES for
* possible roles.
* @param[in] handle The handle parameter is interpreted depending on role:
* - If role is @ref BLE_GAP_TX_POWER_ROLE_CONN, this value is the specific connection handle.
* - If role is @ref BLE_GAP_TX_POWER_ROLE_ADV, the advertising set identified with the advertising handle,
* will use the specified transmit power, and include it in the advertising packet headers if
* @ref ble_gap_adv_properties_t::include_tx_power set.
* - For all other roles handle is ignored.
* @param[in] tx_power Radio transmit power in dBm (see note for accepted values).
*
* @note Supported tx_power values: -40dBm, -20dBm, -16dBm, -12dBm, -8dBm, -4dBm, 0dBm, +3dBm and +4dBm.
* @note The initiator will have the same transmit power as the scanner.
* @note When a connection is created it will inherit the transmit power from the initiator or
* advertiser leading to the connection.
*
* @retval ::NRF_SUCCESS Successfully changed the transmit power.
* @retval ::NRF_ERROR_INVALID_PARAM Invalid parameter(s) supplied.
* @retval ::BLE_ERROR_INVALID_ADV_HANDLE Advertising handle not found.
* @retval ::BLE_ERROR_INVALID_CONN_HANDLE Invalid connection handle supplied.
*/
SVCALL(SD_BLE_GAP_TX_POWER_SET, uint32_t, sd_ble_gap_tx_power_set(uint8_t role, uint16_t handle, int8_t tx_power));
以广播为例：设置的时候一定在开启广播之后，否则返回错误BLE_ERROR_INVALID_ADV_HANDLE，如果设置tx_power的参数不在这个范围-40dBm, -20dBm, -16dBm, -12dBm, -8dBm, -4dBm, 0dBm, +3dBm and +4dBm.返回错误NRF_ERROR_INVALID_PARAM
2.1、单通道广播时候
（1）第一个参数是对应角色的功耗
BLE_GAP_TX_POWER_ROLE_ADV = 1, /**< Advertiser role. */广播发射（从机）
BLE_GAP_TX_POWER_ROLE_SCAN_INIT = 2, /**< Scanner and initiator role. */扫描和发起者发射（主机）
BLE_GAP_TX_POWER_ROLE_CONN = 3, /**< Connection role. */连接
（2）第二个参数对应角色的句柄
开启广播之后的句柄有效：m_advertising.adv_handle
（3）第三个参数功率的级别：-40dBm, -20dBm, -16dBm, -12dBm, -8dBm, -4dBm, 0dBm, +3dBm and +4dBm.填写对应的数字，值越大信号越强。
err_code = sd_ble_gap_tx_power_set(BLE_GAP_TX_POWER_ROLE_ADV, m_advertising.adv_handle , 4); APP_ERROR_CHECK(err_code);
2.2、多通道广播时候
1）第一个参数是对应角色的功耗
BLE_GAP_TX_POWER_ROLE_ADV = 1, /**< Advertiser role. */广播发射（从机）
BLE_GAP_TX_POWER_ROLE_SCAN_INIT = 2, /**< Scanner and initiator role. */扫描和发起者发射（主机）
BLE_GAP_TX_POWER_ROLE_CONN = 3, /**< Connection role. */连接
（2）第二个参数对应角色的句柄
开启广播之后的句柄有效：m_adv_handle
（3）第三个参数功率的级别：-40dBm, -20dBm, -16dBm, -12dBm, -8dBm, -4dBm, 0dBm, +3dBm and +4dBm.填写对应的数字，值越大信号越强。
err_code = sd_ble_gap_tx_power_set(BLE_GAP_TX_POWER_ROLE_ADV, m_adv_handle , 4); APP_ERROR_CHECK(err_code);