I explain my hardware, An MCU + NRF51822, Communication is done via the UART TX RX between them, baud rate is 9600. MCU through UART transmit data to NRF51822, then NRF51822 passes the data to USB dongle. When mcu continuously sent data ( 11Byte/15ms ), data error rate of about 0.15~0.2% whether there are other way to be able to reduce the error rate.