Many folks today like to use their own smartphones in the business environment, hence BYOD as well as tablets. In the case of healthcare, the IT organization may decide to use a certain brand of a “smart phone” for the use in clinical applications. There are perhaps some important things to understand and look at.
First pretty much all “smart phones” are consumer devices that were primarily designed for the consumer in mind. The attractiveness is the display, touch screen, user interface etc. And yes it is a literally a computer with the the ability of making that 3G/4G call.
To build some more value and allow the consumer to not have to incur all that data cellular usage cost (like videos); the manufactures decided to put in a WiFi radio chipset. It could be 802.11a/g/n, this is not really the issue. The main issue to realize is that for the price point that they are selling this at; it is more than likely not a robust radio designed for enterprise application requirements…but to connect to a “hotspot” or your home network. And the real use of the radio would be for data…not voice. Oh yes, most folks would be sitting in their chair.
Wireless voice over IP in the enterprise is a challenging application to just make work right. A lot of variable exist. For instance, the actual WLAN network has to be designed with a signal strength of -65dBm and a co-channel interference of less then 2% (ideal). This includes everywhere where you “think you might make a call…like in an elevator going down between floors”.
Now to the device itself and what is needed after you add a client application for WLAN VoIP. More than the likely the clinician when using a WLAN enabled smart phone for voice is not “standing” under an access point, but will be walking up and down the hallway, inside rooms, etc. on a call taking care of patients. To actually make a WLAN voice over IP call the clinician first has to authenticate to the network via a variety of security schemas that may be different for each institution.
Now this is when it gets interesting. As the person is walking down the hallway on a call, the radio in the “smartphone” has to initiate a nice gradual and clean handoff to the next AP “without” disconnecting while keeping the same authenticated network connection. If the radio algorithms for roaming are not sufficient or if the antenna is not great…the connection will drop. WLAN data is more forgiving as if you lose a few packets…the connection slows downs. However with voice the call is pretty much dropped..
As a side most WLAN radios are power hungry hogs even though this has been improved over the years. So to save power most mobile devices have what they call PSP and CAM modes. PSP (Power Saving Polling), simply means that the phone is idle with the radio on and when the connection is made (like a call), the radio ramps up the power to ensure a reliable connection. This saves a lot of power…thus keeping somebody from having to change batteries or plug it in. In the CAM mode (Continuous Aware Mode), the radio is powered up at the highest power setting to maintain a reliable connection….all the time.
So what does this all mean? A smart phone for WLAN data and WLAN voice over IP needs to last an entire shift in a healthcare setting. The combination of the big display sucking power and perhaps the need to put the device in CAM mode, just means it will not.
Options include charging (during a shift)…not an option…or adding a “sled with a battery”. Now that cool smart phone is a cool brick.
