Traveller Tuesday: Meson Comms

My most recent game session of Traveller involved a Meson Communication to the PC ship, and the comms monkey asked if his ship could reply back. I said no, because they had a receiver but not a transmitter (see below for justification). Then I got to thinking: Mongoose Traveller talks about meson communications, but does it have any actual rules for them?

It turns out that the answer is "no."

Obviously, this post is going to fix that.

My use of Traveller setting and dress falls under
fair use guidelines for both Mongoose and Far Future Enterprises.

Per the Tech Level chart in the MegaTraveller Referee's Companion (and replicated here),  meson communication is experimental at TL 14 and widely available at TL 15. This is interesting as meson guns are available as early as TL 11, which suggests that the difficulty lies in adjusting the intensity of the beam so that it delivers a modulated message rather than exploding its target. (A good analogy for this is a comparison between using atomic weapons in the 1940s vs.  modern day radiosurgery.) From this we can infer that the technological hurdle lies with the transmitter and its yield, and that receiving meson communications is rather simple and can be built at a lower TL.

Therefore I have house-ruled that there are two types of Meson Communicators (hereafter MesComs): those capable of sending and receiving, and those capable of only receiving.

Reception Only
A receiver-only mescom (MesRep) is simply an antenna capable of receiving meson messages and a computer able to translate those messages. As the size requirements for this are very low, any ship with military-grade electronics (TL 10, 2 dtons, 1 MCr.) or higher automatically has meson reception ability. This allows Navy ships to send encrypted communiques to any military asset so equipped, which is useful in battle.

(Naturally, any ship running a meson damper will be unable to receive these messages.)

Transmission 
The price and tonnage for meson transmitters (MesTrans) is taken from the MegaTraveller Referee's Manual p.67:

Since no price is given for TL 14 mescom, even though it is technically available, this indicates that it is experimental and therefore the price is exorbitant.

Converting this from MT to MgT, these options become available at TL 15:

• Short range: 0.5 dtons, 1 MCr. 
• Medium range: 2 dtons, 4 MCr.
• Very Long range: 30 dtons, 10 MCr.
• Distant range: 150 dtons, 20 MCr.
• 1000 AU* range: 500 dtons, 80 MCr.

*1000 AU is roughly 150 BILLION km, which (if measured from the sun) reaches past the Kuiper Belt and halfway to the Oort Cloud.

http://interstellar.jpl.nasa.gov/interstellar/probe/introduction/scale.html

Mounting on Ships

From there, it's a simple deduction:

• All military craft can receive mescoms. 
• Small craft and fighters can mount short range mestrans for half a dton. This is used by wing commanders or CAGs to issue orders to their fighters during battle.
• Dedicated sensor platforms (like the Traveller equivalent of the EF-111A "Spark-Vark") carry the medium range mestrans for 2 dtons, likely at the cost of a hardpoint. 
• Larger ships, like 100+ dton scout craft, can mount the 30 dton very long range mestrans, but this would be rare as that is a significant percentage of cargo space. A 400 dton Aegis-class scout, however, would make a good platform for this if one of the drone bays were removed. 
• Escort-class ships (1000 dtons) and up undoubtedly mount either medium or v.long mestrans. Some might carry a distant range transmitter in lieu of several bays. 
• Capital ships carry a very long rang mestran at the minimum. and flagships undoubtedly carry the 500 dton version for interplanetary ranges. 
• Tonnage on planets is a non-issue (Luna is roughly 1.6275E+18 dtons, or 3.255 trillion Tigress-class Dreadnoughts, so... biggish) which means that having multiple 500 dton installations is easy (and likely linked to deep meson gun defense sites).

Communication Protocol

Any starship computer capable of tracking targets through relative vectors can easily make the calculations necessary for effective meson communication. The difficulty lies in having the ship respond, as it is difficult to pinpoint a source when there is no beam and the particles that make the transmission are bypassing the hull and decaying within the transmitter. (This is, however, a good way to create an ominous "We are watching you" message...)

Two-way communication is as follows:

1. The transmitting ship gets the range of its target. Usually this is done via a comm laser, but any active sensor ping will do. 
2. Transmitting ship then sends the mescom, and within the message are the coordinates so that the receiving ship may reply. 
3. Assuming the recipient can transmit back, it does so. 

Special thanks to Donovan Lambertus for calculating the volume of Luna and to J. Michael Looney, a former sparky, for helping me work out the details of meson comms.