The 3 Most Important Steps In WLAN Deployments; Survey, Design, And Certification by Jim Portaro

The acceptance of RF-Works Medical Grade Wireless Network deployments has been impeccable, literally the highest rating of any of the wireless services we perform. And although Healthcare has always been on the forefront of Wireless LAN (WLAN) and Mobility adoption, we utilize a variation of this design methodology for any industries where performance for a mobile workforce and the need for access to responsive data and resources is paramount.

Other extreme environments where RF-Works has deployed variations of our Wireless Methodology include financial stock exchanges, cruise ships and sports and entertainment venues, all where demanding design requirements are in the mix. Even with those industries included in our experience, we believe there is no vertical that requires a more robust Wireless LAN than healthcare. RF-Works has evolved our design specifications over many years to adequately meet and exceed the expectations of the mobile workforce within a medical environment.

Our design specifications have been developed to carry all of the critical applications in healthcare such as Data, Voice, Video, Imaging, and Location Based Services. RF-Works recommends a standard Medical Grade Network design in all clinical environments. In the past RF-Works has offered tiers of design such as Data Only vs. Voice and Data vs. Voice, Data, and RFID. This mindset has become obsolete due to the critical need for a robust network in a clinical environment and the evolution of the Medical Grade Network initiative and the ability to carry all services now or in the future.

Many demanding environments can learn from this methodology. The following outlines the specifications used in designing a RF-Works Medical Grade Network:

WLAN Implementation Phases

Each RF Design Project should include:

  • Customized Scope of Work
  • Spectrum Analysis based on an active RF survey
  • RF Design and Documentation
  • Access Point (AP) and if required external antenna installation
  • AP, Controllers and Network Software Configuration
  • Certification (Validation to the Design) and Final Documentation

WLAN System should be designed for the following services

  • Voice
  • Data
  • Video and Imaging
  • LBS/RTLS/RFID
  • Guest/Physician/ Access and QoE
  • PACS Imaging
  • 11 a/b/g/n/ac – 2.4 GHz and 5 GHz
  • Translation Services
  • Temperature Monitoring
  • Life Safety and Security

– Spectrum analysis to be performed for all areas to be designed in both 2.4 and 5 GHz ISM spectrums (additional recommendations in spectrum analysis available)

– WLAN Services Implications

  • Voice – Could be 802.11a/b/g/n/ac devices
    • SNR minimum – 25 dB
    • Cell coverage should have 15% overlap at approximately -65 dBm
    • Power should be kept low or equal to voice devices
  • Location Based Services
    • RF cell sizes should be less than 2,500 sq ft on average
    • Client should be able to see minimum 3 AP’s on opposite sides for triangulation, preferably four or more
    • AP placement should be pushed to the perimeter for better triangulation on the fringes of the floor while minimizing RF bleed

– Survey-AP and Survey-Client settings based on requirements

– AP Placement and the use of external antennas requires conversations about tradeoffs

– AP Density requires conversations and data from the active survey

– Signal Strength and Quality should adhere to SNR – 25 dB

– Certification Process similar to survey but checking coverage for as-built WLAN while making power and channel adjustments as necessary

– Verify data throughput can be accomplished utilizing different tools, but must be done

– Checking roaming performance with no more than one packet lost on a roam, contact us for best settings

– Design Document includes at a minimum each site description, design objectives, survey procedures, equipment used description, time-stamped spectrum findings by area, interference, power and channel settings, radio and Ethernet MAC address, digital picture, location description, external antenna type if required, coverage maps and bill of materials

– As-Built Document is the same as the design document with any changes made during certification and updated digital pictures from the installation