High-Density and De-Densified Smart Campus Communications. Daniel Minoli

High-Density and De-Densified Smart Campus Communications - Daniel  Minoli


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both technologies fill a role, and both technologies are clearly needed.

      There are several Wireless Local Area (WLAN) standards that have evolved over time, including Institute of Electrical and Electronics Engineers (IEEE) standards 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, 802.11ax. The new standards have been developed to accommodate the evolving requirements for higher speeds. Some protocols and wireless routers provide backward compatibility with older Wi‐Fi systems. The Wi‐Fi Alliance (an industry group) has announced a banding “generation” designation, as follows:

       Wi‐Fi 4 is 802.11n, released in 2009

       Wi‐Fi 5 is 802.11ac, released in 2014

       Wi‐Fi 6 is the new version, also known as 802.11ax (scheduled for release in 2019)

      Earlier versions of Wi‐Fi have not been officially branded, but one could label the previous generations as follows:

       Wi‐Fi 1: 802.11b, released in 1999

       Wi‐Fi 2: 802.11a, released in 1999

       Wi‐Fi 3: 802.11g, released in 2003

      The upcoming 5G access networks may utilize higher frequencies (i.e. > 6 GHz) to support increasing capacity by allocating larger operating channels and bands, although some lower frequencies can also be used. Millimeter wave (mmWave), the band of spectrum between 30 and 300 GHz, have shorter wavelengths that range from 10 to 1 mm. Currently, much of the mmWave spectrum is underutilized; thus, it can be used to facilitate the deployment of new high‐speed services. While it is known that mmWave signals experience severe path loss, penetration loss, and fading, the shorter wavelength at mmWave frequencies also allows more antennas to be packed in the same physical dimension, which allows for large‐scale spatial multiplexing and highly directional beamforming [8].

      One million connections per square kilometer (also definable as 1 connection per m2) equates to one connection every 10 ft2 (1 km2 = 10 763 910 ft2); this is considerably higher than the connectivity goals in an office environment, where typically one has an allocated space of 130–150 ft2 per worker, with one or two connections per worker; this is also higher than the connectivity in a classroom (say a 40 × 40 ft locale and 32 students, or one connection every 50 ft2). Another example could be train cars with 200 users (perhaps not all simultaneously active) in 1000 ft2, or one connection every 10 ft2 if only 50% of the passengers are active at any one point in time.

Key Performance Indicators Description
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