Spatial capacity is an indicator of "
data intensity" in a
transmission
Transmission may refer to:
Medicine, science and technology
* Power transmission
** Electric power transmission
** Propulsion transmission, technology allowing controlled application of power
*** Automatic transmission
*** Manual transmission
*** ...
medium. It is usually used in conjunction with wireless transport mechanisms. This is analogous to the way that
lumens
The lumen (symbol: lm) is the unit of luminous flux, a measure of the total quantity of visible light emitted by a source per unit of time, in the International System of Units (SI). Luminous flux differs from power ( radiant flux) in that radia ...
per square meter determine
illumination intensity.
Spatial capacity focuses not only on
bit rates for
data transfer but on bit rates available in confined spaces defined by short transmission ranges. It is measured in bits per second per square meter.
Among those leading research in spatial capacity are Jan Rabaey at the
University of California, Berkeley. Some have suggested the term "spatial efficiency" as more descriptive. Marc Weiser, former chief technologist of
Xerox PARC, was another contributor to the field who commented on the importance of spatial capacity.
The
System spectral efficiency
Spectral efficiency, spectrum efficiency or bandwidth efficiency refers to the information rate that can be transmitted over a given bandwidth in a specific communication system. It is a measure of how efficiently a limited frequency spectrum is ut ...
is the spatial capacity divided by the bandwidth in hertz of the available frequency band.
Relative spatial capacities
Engineers at
Intel and elsewhere have reported the relative spatial capacities of various wireless technologies as follows:
*
IEEE 802.11b 1,000 (bit/s)/m²
*
Bluetooth 30,000 (bit/s)/m²
*
IEEE 802.11a 83,000 (bit/s)/m²
*
Ultra-wideband 1,000,000 (bit/s)/m²
*
IEEE 802.11g
IEEE 802.11g-2003 or 802.11g is an amendment to the IEEE 802.11 specification that operates in the 2.4 GHz microwave band. The standard has extended throughput to up to 54 Mbit/s using the same 20 MHz bandwidth as 802.11b uses to achieve 11 Mbit/ ...
N/A
See also
*
System spectral efficiency
Spectral efficiency, spectrum efficiency or bandwidth efficiency refers to the information rate that can be transmitted over a given bandwidth in a specific communication system. It is a measure of how efficiently a limited frequency spectrum is ut ...
References
{{Reflist
Wireless networking
Network performance
Radio resource management