Yoga 13 WiFi and bluetooth issue resolved

Question

Unfortunately, I also met WiFi problems, but also found unexpected and sad solution.
Wifi worked pretty well at working place, but had problems at home. As an experiment I brought WiFi router from the working place home. It did not work!
At home I used pretty old keyboard and mouse plugged into passive USB hub. As soon as they were disconnected, problems disappeared. WiFi was also stable after I plugged power supply into the USB hub.
We are making 24-bit analog-to-digital converter that connects to the PC via USB. I exactly know its current consumption (300 to 330 mA) and know that it correctly handles USB rules about power regulations. Maximum current, specified by USB2.0 standard, is 500mA, so consumption of our ADC is within limits. As soon as I plug this ADC in, WiFi connection immediately disappears at the working place.
In the case of other devices, such as USB flash drive, power consumption may depend on the activity, increasing as it writes or reads something, and decreasing at the moment of inactivity.
I'm pretty sure that Lenovo placed their WiFi/bluetooth module on the same USB hub with right-side USB2 connector. Any device, that requires energy, being plugged into USB2.0 port, immediately destroys WiFi (and presumably bluetooth) and it is rather hard to get it back alive without special dancing around.
So, conclusion: never plug anything into USB2.0 port, if you need WiFi. This decreases number of available USB ports from two to one. Lenovo team should be blamed for that, not driver manufacturers or board manufacturers - Lenovo did non do its construction job well.
I am not sure, that all WiFi and bluetooth problems of Yoga discussed at this forum have the same reason. But in any case incorrect implementation of USB2.0 power should be considered before any other reason of malfunction.
Car manufacturers recall their products in the case of a failure. What about computer manufacturers?

Answer 1

Citation from Wikipedia:
The USB 1.x and 2.0 specifications provide a 5 V supply on a single wire to power connected USB devices. The specification provides for no more than 5.25 V and no less than 4.75 V (5 V ± 5%) between the positive and negative bus power lines. For USB 3.0, the voltage supplied by low-powered hub ports is 4.45–5.25 V.[61]
A unit load is defined as 100 mA in USB 2.0, and 150 mA in USB 3.0. A device may draw a maximum of 5 unit loads (500 mA) from a port in USB 2.0; 6 (900 mA) in USB 3.0. There are two types of devices: low-power and high-power. A low-power device draws at most 1 unit load, with minimum operating voltage of 4.4 V in USB 2.0, and 4 V in USB 3.0. A high-power device draws, at most, the maximum number of unit loads the standard permits. Every device functions initially as low-power — but may request high-power, and get it if available on the providing bus.[62]
Obviously, WiFi adapter is a high-power device. If it does not have sufficient power, it will start power saving program by reducing speed. Even lower power may interrupt ins basic functions. When I connect another high-power device (HDD or ADC) to the same hub, it should get its 500mA from the hub. Seems that starting at this moment  WiFi receives much less current than it requires and stops working. 
If something is plugged into USB3 port, and this something does not utilize all energy it requested, WiFi starts working again.
I would greatly appreciate if somebody repeats my tests using Yoga or Yoga 2 Pro.
Test:
Reboot your system, all USB devices disconnected
Open http://www.speedtest.net site and measure Download connection speed (Speed1)
Connect external HDD to USB2 (NOT USB3!) port
Wait until HDD is connected
Test Download speed once again (Speed2)
Report results to this blog as Speed1/Speed2 couple of numbers
Thank you in advance