Different organisations require different Wi-Fi installations, and perhaps none is so complicated than that of a healthcare environment. There are many obstacles and potential issues to consider.
As with all networks, reliability is key. With a wide range of different services on a healthcare WLANS, such as Electronic Health Records, RTLS, guest internet, VoWi-Fi, not to mention the many biomedical devices present, it’s imperative that these networks are designed properly and cohesively.
Where to Start – Consultation and Identification of Symptoms
First and foremost, the Wi-Fi coverage is not the main concern when designing a hospital – The needs of a healthcare organisation are complex and varied. For the WLAN design to meet the unique set of requirements that the above services need, they must be combined together to determine the best possible outcome for all.
The first stage of this process is a Site Assessment or Wi-Fi Survey. Perhaps there is already a WLAN in place, in which case the primary port of call would be to see what issues, if any, arise within this one.
The survey should show up any interference, identify any gaps in coverage and find any misconfigurations. A great start! Another important starting point is attenuation – seeing how signals perform and locating areas where there is no or limited propagation through walls.
There are many possible sources of interference in a hospital, including but not limited to surgical cameras, security cameras and everything inbetween. There are specialist adapters that can be used during site surveys to pick up and record the sources of interference so that these can be avoided when deciding where to place Access Points, for example.
Much like an MRI can act as a patient’s basic map, a floor plan in your hands as you walk around the facility can act as a tool to mark areas of consideration. For example, noting wall and ceiling construction – This information will be invaluable when planning accessibility for cabling installation during the design process. It is also useful to note down good potential areas to install access points – There may also be areas you will wish to avoid for signal reasons (e.g. lift shafts, areas over 90m from the telecommunications closet, places with high moisture levels, and rooms wrapped in metal) as well as personal preference of employees.
These floor plans need to be as recent as possible, or at least checked for accuracy to include any changes made between the original plans and the most recent construction adaptations.
We mentioned attenuation earlier. There are 2 main ways of gathering data for Radio Frequency. The first is using a portable access point (APoaS) which enables you to place it in different proposed locations and assess where the signals propagate. Another option is to use a signal meter to directly measure the decibel loss between an access point and the other side of a wall.
The Next Step – Diagnosis
Once you’ve completed the Site Survey, you are ready to start your diagnosis and begin to design a Wi-Fi network that meets the needs of the healthcare organisation.
Real-time locating systems (RTLS) are used to automatically identify and track the location of objects or people in real time, usually within a building or other contained area.Within a healthcare organisation, any assets which are part of this system will need to be surrounded by access points. It is suggested that you start your design from the outer edge of the building and then work your way in. The goal of the WLAN design is to ensure that these assets are ‘heard’ by at least 3 access points, and at an acceptable level of signal.
There is specialist software that you can use to create a model of what your wireless network will look like. This software uses real-world data and can be an extreely useful tool during the design process.
We spoke about the important of checking the propagation of signals. This information will give you the values you need to use in your design. This again enables you to model your WAN with your chosen software.
When designing the interior of the organisation, you need to make sure that the capacity, RTLS, voice and data requirements are met with a 5GHz WLAN. One particular function that requires two 5GHz worth of signal coverage is VoWifi. Where Wi-Fi is used to transmit telephone conversations, the access points need to be placed as close to where the clients will congregate as possible. For example, meeting rooms, break rooms, waiting areas and nursing stations.
It’s not only VoWiFi sets that will be using these either, as the staff members will likely be carrying smart phones or devices as well so it needs to be able to cope with the amount of connections.
When designing for voice, you will need the information gleaned from checking “2nd strongest” on the frequency band to check AP overlap requirements.
During the design stage, depending on how many channels you are using you will likely need to reduce to 40 or 20 MHz. This is because the hospital environment tends to have more access points.
As you will be designing for a multi-floor facility, attenuation and propagation characteristics will need to be taken into account not only for walls but ceilings and between floors aswell. You should be able to monitor the 2nd strongest signal strength, channel overlap and network health during this process.
Once you have finished designing, you can then build. configure and validate your WLAN.
As with all diagnoses, you will need to be ready to modify your treatment plan following the discovery of new symptoms or treatments that don’t work. During the construction of your network, you may find that you need to modify your design according to any unexpected issues that arise. For example, locations of access points may need to adhere to multiple requests from different people. You can use your software to ensure that any changes will also meet the other requirements specified.
Administering a Treatment Plan
Hopefully when you’ve administered your prescription, the treatment will be effective – Following the build of your new WLAN, you will need to validate it’s effectiveness by carrying out a validation survey. The most important part of this, is to show whether the deployment matches your original design – Does the treatment meet the diagnosis? Be sure to use the channels used in your design in your deployment – The software you have used should have used real world data and thus should have pre-determined what will work.
Use your chosen software to assist you in tuning. Look at the Signal Strength, Channel Overlap, Signal-to-Noise Ratio (SNR) and Network Health views. There is of course a possibility that what you designed may not quite carry over onto the actual access points or controllers, in which case you may need to adjust channels and work around unexpected interference.
Take your time with the tuning element, as this is what will help ensure overall effectiveness. Make sure your access points are installed as designed, and are placed in such a way as to not negatively affect coverage patterns.
Just as we all need regular check ups from time to time, the best way to keep your WLAN healthy is to carry out regular validation surveys. Once the network is in use, you may start to get feedback from users in terms of problem areas which will need to be addressed. Having a visual representation of signal strength within your design software is a particularly handy tool to have.
Here are a few general Do’s and Don’ts when designing a Wi-Fi network for a healthcare organisation.
Do….
– Utilise the software available. Learn how to use it properly, even take a class on it if needs be!
– If you are not sure how to design a WLAN, then learn properly first. Look at books, online guides or even hire in a professional to do the hard work for you.
– Make sure to gather all of your requirements – Voice, Data, Location, Capacity, Applications.
– Get as much information as possible – Ask plenty of questions during site visits, and even try to talk to those that will be using it.
– Observe the users in action – Particularly for VoWiFi, watch for traffic flows, where people tend to congregate, identify any current problem areas or issues.
– Look at their current WLAN and find out exactly what it does. Is it meeting their needs? Will their needs change?
Don’t…
– During the design process, do not place access points too close together, higher than ten feet, or hanging on a wall.
– Do not be tempted to cut corners and design the WLAN sitting at your desk. You need to complete the on-site survey and do so in detail.
– Remember you are not just designing simply for coverage. For healthcare you need to take all of them into account.
– Installation of access points can be easier if they are all lined up, but do not be tempted to do this. These so called “Hall-Fi” designs create co-Channel interference (CCI) which will reduce your WLAN capacity.
– Don’t be tempted to generalise by using ‘lazy’ WLAN design statements. Saying “one access point per three patient rooms”, or “one access point per 1,000 square feet” is counter-productive and may not achieve the best results. More detail than that is needed.
– Don’t skip the validation stage. Once your WLAN is built, be prepared to adjust your design following the results. A good doctor won’t keep repeating a prescription when the medicine isn’t working – They will reassess the symptoms and adjust their treatment plan accordingly.
At Geekabit, we are experts at designing and installing networks. To discuss your Wi-Fi requirements, contact us through one of the below.
London 0203 322 2443 | Cardiff: 02920 676 712 | Winchester: 01962 657 390 | info@geekabit.co.uk
Photo via http://drwifi.rescatec.com/ with thanks.
See also: https://www.ekahau.com/blog/2017/06/06/dos-donts-healthcare-wi-fi/
