In order for a group to function smoothly there must be a means of communication.  The vastness of space complicates this communication due the the time it takes for messages to reach distant ships, bases or other locations.

Relay Station

"The speed of propagation of a subspace signal continues to be the limiting factor in any long-range communications. Subspace radio signals, even those tightly focused and radially polarized, will decay over time, as the energies forced across the subspace threshold will tend to 'surface' to become normal slower EM. As this decay occurs, enormous amounts of information are lost, since the modulated signal does not decay evenly. The propagation speed under ideal galactic conditions is equivalent to Warp Factor 9.9997. This places subspace radio about sixty times faster than the fastest starship, either existing or predicted. The phenomenon, which occurs at distances proportional to the peak radiated power of the outgoing beam with an upper distance limit of 22.65 light years, has necessitated the placement of untended relay booster beacons and small numbers of crew-tended communications bases at intervals of twenty light years, forming irregular strings of cells along major trade lanes and areas of ongoing exploration." -- (TNG Tech Manual pg 99).

Communications in localized areas, such as onboard a Starship, Starbase or other installation, as well as planets; are not hampered by these distance problems.  The only lag that may be experienced is waiting for the person contacted to reply.

In the late 2370's Transwarp technology began testing to increase the propogation speed of long-range communications between relay stations.  Once an initial transwarp corridor was established propagation speeds were able to hold consistent at 500,000 times light speed.  By 2382 Transwarp Communication conversion for all Relay stations, Bases, outposts, planets and other facilities started.  Relay stations remained at 20 LY, and data transmission times between stations using the new system dropped from 55 minutes to only 21 minutes.  At present there is no Transwarp Communication upgrade for Starships since they are not 'fixed' locations.

Communicator (TOS Era)Early Communicators were patterned after 20th Century Terran 'cellular phones'.  They were usually only assigned to members of away teams so the landing party could remain in contact with each other.

To activate the device the cover is raised.  The dials may be used to fine-tune the transmission to overcome any interference.  The buttons are used when verbal communications aren't possible, they consist of a green button for "all clear", a yellow button for "stand by", and a red button for "emergency".

As technology improved the Communicator shrunk in size.  For members of Starfleet or other military it became a 'badge' or other insignia worn upon their clothing.  Originally to activate the device it had to be 'tapped', later it was merely voice-activated. Commbadge

Desktop CommunicatorDesktop and Wall mounted Communication panels are used in much the same purpose.  Generally a button must be pressed to activate the device.

Improvements in technolgy during the Dominion War led to a new form of communications which merged Communications with Holo-technology.  Locations (both sender and receiver) equipped with holo-cameras and emitters may use Holo-Communications in which the other person appears in your location as a hologram.  This technology is generally not used over long-distances due to the large delay time.

All communicators also provide Universal Translator function to assist in discussions when needed.

COMM System
There are three primary components to the COMM System:
Short Range - using commbadges or communicators.
Long Range - subspace communications.
Security (Encryption) Rating (table below).
The min. vessel size column lists the size required for that item.

Strength Short Range
Long Range
Min. Vessel Size
45,000 KM
~0.25 LY
Class 0
50,000 KM
~10 LY
Class 1
55,000 KM
~22 LY 1
Class 2
60,000 KM
~22 LY
Class 3
65,000 KM
~22 LY 2
Class 4
70,000 KM
~22 LY 3
Class 5
75,000 KM ~23 LY 3
Class 6
80,000 KM ~23 LY
Class 7
85,000 KM ~23 LY
Class 8
90,000 KM ~24 LY
Class 9
95,000 KM ~24 LY
Class 10
100,000 KM ~24 LY
*Transwarp 1
~30 LY
Basic long-range communications use subspace relays travelling at Warp 9.9997, however even at that speed the signal degrades after approximately 22.65 LY, thus relay stations are positioned at roughly 20-22 LY intervals to receive the signals and relay them onward.
* Transwarp Communications are available for Starbases, outposts and/or land-based facilities after 2382, it is NOT available for Starships.

Security Rating
The Security Rating for a COMM system provides data encryption / decryption for transmissions, and allows communication through some jamming fields or natural interference such as ion storms.
Delta 80%
Percentages for Cryptography indicate the difficulty of a message to be decoded.
Percentages for Anti-Interference indicate the ability of cut through interference (natural or artificial).

With the wider use of Holo-technology came the potential for 'face to face' conversations rather than computer screen.
For 'real time' conversation those involved must be within 10 LY otherwise significant time-lags will occur.

Ships built before 2300 are not able to utilize shipwide holo-technology due to power, structural and computer needs.
Ships built between 2300-2340 may undergo a major upgrade to allow shipwide Holo-technology.
Ships built after 2340 would need either major or minor upgrade depending on the class.

Computer core: Isolinear, Bio-Neural, ICE, or B-ICE
EPS system: "High" or "Shielded" class
ODN system: "High" or "Shielded" class

The upgrade would typically replace the EPS and ODN lines to 'high' ratings, and install holo-emitters.
Areas that already have Holo-emitters (Holodecks, Holosuites, Sickbay, etc...) automatically receive Holocommunications.