BasicRF点对点控制LED灯开关例程中，增加light设备个数后传输距离降低很多。

static void appSwitch()
{
 //   halLcdWriteLine(HAL_LCD_LINE_1, "Switch");
  //  halLcdWriteLine(HAL_LCD_LINE_2, "Joystick Push");
  //  halLcdWriteLine(HAL_LCD_LINE_3, "Send Command");
  int a=0,b=0,c=0,d=0;
  InitKeyswi();
#ifdef ASSY_EXP4618_CC2420
    halLcdClearLine(1);
    halLcdWriteSymbol(HAL_LCD_SYMBOL_TX, 1);
#endif

    pTxData[0] = LIGHT_TOGGLE_CMD;

    // Initialize BasicRF
    basicRfConfig.myAddr = SWITCH_ADDR;
    if(basicRfInit(&basicRfConfig)==FAILED) {
      HAL_ASSERT(FALSE);
    }

    // Keep Receiver off when not needed to save power
    basicRfReceiveOff();

    // Main loop
    while (TRUE) {
      //  if( halJoystickPushed() ) {  //bu qiujie tech
      a=KeyScan1();
      b=KeyScan2();
      c=KeyScan3();
      d=KeyScan4();
      if(a){

            basicRfSendPacket(LIGHT_ADDR1, pTxData, APP_PAYLOAD_LENGTH);

            // Put MCU to sleep. It will wake up on joystick interrupt
            halIntOff();
            halMcuSetLowPowerMode(HAL_MCU_LPM_3); // Will turn on global
            // interrupt enable
            halIntOn();

        }
       if(b){

            basicRfSendPacket(LIGHT_ADDR2, pTxData, APP_PAYLOAD_LENGTH);

            // Put MCU to sleep. It will wake up on joystick interrupt
            halIntOff();
            halMcuSetLowPowerMode(HAL_MCU_LPM_3); // Will turn on global
            // interrupt enable
            halIntOn();

        }
       if(c){

            basicRfSendPacket(LIGHT_ADDR3, pTxData, APP_PAYLOAD_LENGTH);

            // Put MCU to sleep. It will wake up on joystick interrupt
            halIntOff();
            halMcuSetLowPowerMode(HAL_MCU_LPM_3); // Will turn on global
            // interrupt enable
            halIntOn();

        }
      if(d){
basicRfSendPacket(LIGHT_ADDR1, pTxData, APP_PAYLOAD_LENGTH);

            // Put MCU to sleep. It will wake up on joystick interrupt
            halIntOff();
            halMcuSetLowPowerMode(HAL_MCU_LPM_3); // Will turn on global
            // interrupt enable
            halIntOn();
           
            basicRfSendPacket(LIGHT_ADDR2, pTxData, APP_PAYLOAD_LENGTH);

            // Put MCU to sleep. It will wake up on joystick interrupt
            halIntOff();
            halMcuSetLowPowerMode(HAL_MCU_LPM_3); // Will turn on global
            // interrupt enable
            halIntOn();

            basicRfSendPacket(LIGHT_ADDR3, pTxData, APP_PAYLOAD_LENGTH);

            // Put MCU to sleep. It will wake up on joystick interrupt
            halIntOff();
            halMcuSetLowPowerMode(HAL_MCU_LPM_3); // Will turn on global
            // interrupt enable
            halIntOn();

        }
    }
}