SHIELD OPERATING FREQUENCIES

	Providing shielding against the entire spectrum of electromagnetic 
radiation would prove far too energy-costly for normal Cruise Mode use. 
Additionally, a full-spectrum shielding system would prevent onboard 
sensors from gathering many types of scientific and tactical data. Instead, 
Cruise Mode operating rules allow for deflectors to operate at the relatively 
low level (approximately 5% of rated output) and at the specific frequency 
bands necessary to protect the spacecraftÕs habitable volume to SFRA-
standard 347.3(a) levels for EM and nuclear radiation.

	During Alert situations, shields are raised to defensive configuration 
by increasing generator power to at least 85% of rated output. Shield 
modulation frequencies and band-widths are randomly varied to prevent a 
Threat force from adjusting the frequency of a directed energy weapon 
(such as a phaser) to penetrate shields by matching frequency and phase. 
Conversely, when the frequency characteristics of a directed energy 
weapon are known, it is possible to dramatically increase deflector 
efficiency by adjusting the shielding frequencies to match those of the 
incoming weapon. Similar techniques are used to protect the vehicle against 
various natural hazards, as when shielding is increased in the 10¸ meter 
band to protect against X rays generated by a supernova.

	Raising shields to defensive configuration also triggers a number of 
special operating rules. First, active sensor scans are operated according to 
special protocols that are intended to minimize the interference due to the 
shielding effects. For certain types of scans, sensors are continually 
recalibrated to take advantage of any EM ÒwindowsÓ left open by rotation of 
shield frequencies. In other cases, the random variation of shield 
frequencies is modified slightly to allow a specific EM window at specific 
intervals necessary for data collection. Such sensor operation techniques 
generally result in substantially reduced data collection rates, so sensor 
usage is strictly prioritized during Alert situations. Further, most defensive 
scenarios require sensors to be operated in Òsilent runningÓ mode during 
which the usage of active scan sensors is not permitted and only passive 
sensors may be used.

	Also affected by deflector shield usage is operation of the transporter 
system. The annular confinement beam that serves as the transmission 
medium for the transporter beam requires such a wide EM and subspace 
bandwidth that it is normally impossible to transport through shields. 
Additionally, the shieldsÕ spatial distortion effects can be severely disruptive 
of the transporter beamÕs pattern integrity.

	Shield operation also has a significant impact on warp drive 
operation. Because of the spatial distortion inherent in the shielding 
generation process, there is a measurable effect on the geometry of the 
warp fields that propel the ship. Warp drive control software therefore 
includes a number of routines designed to compensate for the presence of 
deflector shields, which would otherwise cause (at maximum rated output) a 
32% degradation in force coupling energy transfer. Simultaneously, shield 
generator output must be upshifted by approximately 147 kilohertz to 
compensate for translational field interaction.  Æ