RPG Forums

Go Back   RPG Forums > Role Playing Game Section > Morrow Project/ Project Phoenix Forum

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 01-30-2011, 06:49 PM
robj3 robj3 is offline
Some bloke
 
Join Date: Dec 2010
Location: Newcastle NSW
Posts: 51
Default Radios, meteors and the Morrow Project

How does the wakeup signal get to a bolthole, anyway?

The problem is comparable with communicating with submarines at sea;
ground penetration of radio waves is limited by soil and rock moisture and electrolyte content. High electrical conductivity causes attenuation of the signal.

The transmitter needs to have a wide range and also be relatively easy to disguise.

Transmission should not depend on satellites for propagation, given the limited usable lifetime of satellites. Not needing certain atmospheric conditions for signal propagation would be useful, but this limits the available range of frequencies.

On the receiving end, above ground antennae also have to be limited in height and size otherwise concealment becomes difficult. Buried antennae need to be larger to compensate for the attenuating effects of the ground. This would require large amounts of land, especially in the case of lower frequencies/longer wavelengths (see below).


* Meteor Burst Communications
Meteors continually enter the Earth's atmosphere; as they burn up they ionise the surrounding air. This enables radio transmissions to be bounced off these ionisation trails, which typically occur at an altitude of 50-75 miles (80-121km).
Stations can be up to 1,243 miles (2,000km) apart.

Low frequency (30-300kHz) transmissions can propagate this far, but large antennae are required (up to 200+m in height) e.g. the LORAN (long range navigation) network.

Frequencies in the VHF band over the 30-100MHz range can be used. The optimum for maximum range is 40-50MHz.

A master station transmits a probe signal into the upper atmosphere. Remote stations wait to receive the probe signal reflected off a meteor trail. They then transmit a message back to the master station that a communication channel is open. The master then acknowledges the remote station and communications begin.

Another option is that the master repeatedly transmits to an array of remote stations.
The remotes are in a receive mode only. Given enough time a channel will open to all the remotes.

The main problem is a relatively low bandwidth due to the fleeting (~0.5 second) and random nature of meteor trails (varies with time of day and year; delays of several minutes are possible, but usual wait times are less than 90 seconds).
Despite needing to send information in short bursts, transmission rates of over four kilobits per second are possible.

Transmitters and receivers can be small: 10.6" x 4" x 2.42" (26.9 x 10.2 x 13.5 cm).

Antennae are relatively small: 2-3m (7-10ft) for portable systems, 10-15m (30-50ft) for large base stations. Transmission power ranges from 100W to 1kW (the maximum transmitter power for a civilian AM radio station today in North America is 50kW).

The best known meteor-burst communication system is used by SNOTEL (snow telemetry).
It has been operated by the USDA since 1977 and measures and transmits snowpack and precipitation data from over 700 locations across the Western United States, including Alaska.

COMET was a military system used by NATO from 1965 with stations in the Netherlands, France, Italy West Germany, Norway and the United Kingdom. Data rate was 115-310 bits per second.

Meteor burst systems look like a good modality for longer-range Project communications.
They are portable, secure and offer over the horizon capability without the need for satellites or other relays.

* Shortwave
Also known as high frequency (3-30MHz). It is possible to communicate around the world over this band, provided atmospheric conditions are suitable; the radio waves are refracted by the ionosphere.

Time of day, season and solar activity affect the ionosphere and thus the maximum range obtainable.

Frequencies above 12MHz propagate better during the day; at night, the converse is true.

Solar activity (especially flares) reduces shortwave range.

In the short term after a nuclear exchange, widespread atmospheric ionisation will also adversely affect range; a much smaller interference effect can be seen with thunderstorms.

Shortwave antennae can be quite small, on the order of a foot (0.3m); longer range transmitters and receivers require larger systems (the extreme case being several hundred yards [metres] for a buried antenna with intercontinental range).


* What about ELF?
Extremely Low Frequency (ELF) radio uses frequencies between 30 and 300Hz; the problem is that extremely large antennae are required for transmitters.

In addition there are severe geological restrictions - access to large areas of
low-conductivity rock is needed.

The original plan for the U.S. ELF transmitter, Project Sanguine, would have used an area equivalent to 2/5 of the state of Wisconsin (~21,992 sq. miles or 56,960 km^2).
Three locations were considered: Nevada (Nellis AFB, Nevada Test Site); New Mexico (White Sands/Fort Bliss); and the upper peninsula of Michigan.

This would have used the Laurentian granite bedrock of the Lake Superior region as a giant antenna. 6,000 miles (9,650km) of cable would be tunneled through the rock to form an antenna grid.

The proposal was vetoed because of potential biological effects. Enormous quantities of power would be required to energise the antenna.

A smaller version, Project ELF, became operational in 1989. It was dismantled in 2004.
There were two antennae, one near Clam Lake, WI, and the other near Republic, MI.

The Wisconsin antenna was made up of two 14 mile (22.53km) lines, the Michigan three lines - two 14 miles (22.53km) long, and one 28 (45.06km) long. The antennae were mounted on 40ft (12m) telegraph poles and had a cruciform arrangement.
The attendant transmitter facilities were six (MI) and two (WI) acres (2.4 and 0.8 ha) in size. They were connected by a 165 mile (265.5km) cable.

Transmission power was on the order of 5 megawatts.

A road mobile system with 30 miles of cable (lay grid out on road) was investigated.

On the receiving end, a submarine deploys a wire antenna several hundred yards (metres) long. ELF waves will penetrate several hundred yards (metres) of seawater.

The data transmission rate is slow, on the order of 1 bit every 1-10,000 seconds.
As a result, a submarine usually ascends to a depth where faster communications are possible.


* What about VLF?
Very Low Frequency (3-30 kHz) signals are also used to communicate with submarines.
They can penetrate sea water up to 40m deep, depending on frequency and salinity.

Transmission and reception antennae also need to be quite large.
For the TACAMO system, aircraft deployed a 5 mile (8km) wire antenna to transmit to submarines. The receiving antennae were similar in length to the ELF system.

Terrestrial transmitters occupy several acres. Transmitter power 1-3MW.

The following sites formed the U.S. strategic VLF communications network:
- Northwest Cape, Exmouth, Western Australia
- Yosemi, Japan
- Rugby, UK
- Anthorn, UK
- Wahiawa, Hawaii
- Annapolis, MD
- Cutler, ME
- Jim Creek, WA


* Maintaining communications after nuclear attack: GWEN
The Ground Wave Emergency Network (GWEN) was built in the 1980s to provide a secure communication infrastructure for U.S. strategic forces. It was designed to be resistant to electromagnetic pulse and have the ability to route data packets around damaged nodes like the Internet (packet switching).

Transmission would not rely on bouncing off the ionosphere for range
(low frequency at 150-175kHz).

58 290ft (88m) transmission towers were built across CONUS. 49 access terminals were distributed.

GWEN was defunded in 1998. Its functions were covered by the existing Survivable Low Frequency Communications System (SLFCS) operated by SAC/STRATCOM and the Minimum Essential Emergency Communications Network (MEECN). SLFCS/MEECN were also connected into the Navy's VLF/ELF system.

SLFCS transmitted from four locations:
- Silver Creek, Nebraska
- Hawes AFS, California
- Post Attack Command and Control System aircraft (5 on alert in the northern U.S.)
- The National Emergency Airborne Command Post (National Airborne Operations Centre)

Terrestrial (VLF/LF) antennae were buried, increasing their survivability.

Messages were relayed to bombers via the GREEN PINE stations in Alaska and Canada.

Ground based receiving stations were at the bomber and ICBM bases.

MEECN replaced SLFCS in 2005. This has satellite uplink capacity to the Milstar constellation as well as the low frequency (14-60kHz) bands used by SLFCS.


Rob

=============

* References
http://en.wikipedia.org/wiki/Radio_propagation

Underground and underwater(!) antennae from the early days of radio:
http://www.rexresearch.com/rogers/1rogers.htm

= Meteor Burst Communications
http://en.wikipedia.org/wiki/Meteor_...communications
http://en.wikipedia.org/wiki/SNOTEL
http://www.meteorcomm.com/technologies/tech_burst.aspx
Cohen D., Grant W., and Steele F.NTIA Report 89-241. Meteor Burst System Communications
Compatibility. U.S. Department of Commerce, March 1989.
Haakinson E.J. NTIA Report 83-116. Meteor Burst Communications Model. U.S. Department
of Commerce, February 1983.
http://en.wikipedia.org/wiki/LORAN-C

= Shortwave
http://en.wikipedia.org/wiki/Shortwave

= ELF
http://en.wikipedia.org/wiki/Extremely_low_frequency
http://en.wikipedia.org/wiki/Communi...ith_submarines
http://enterprise.spawar.navy.mil/Up...ke_elf2003.pdf
http://www.plrc.org/docs/941005B.pdf
Schwartz S., et al. Atomic Audit: the costs and consequences of U.S. nuclear weapons
since 1940. The Brookings Institution, 1998. p.215

= VLF
http://en.wikipedia.org/wiki/Very_Low_Frequency
http://www.globalsecurity.org/wmd/systems/e-6.htm
Schwartz S., et al. Atomic Audit: the costs and consequences of U.S. nuclear weapons
since 1940. The Brookings Institution, 1998. p.209, 214-215

= GWEN
Foster N. Citizens jam nuclear radio network. Bulletin of the Atomic Scientists
44:9 (Nov 1988). p.21-26
http://en.wikipedia.org/wiki/Ground_...rgency_Network
http://en.wikipedia.org/wiki/SLFCS
http://en.wikipedia.org/wiki/MEECN
http://www.globalsecurity.org/wmd/systems/gwen.htm
http://www.globalsecurity.org/wmd/systems/slfcs.htm
http://www.globalsecurity.org/wmd/systems/meecn.htm
Reply With Quote
  #2  
Old 02-02-2011, 12:43 PM
nuke11 nuke11 is offline
Registered User
 
Join Date: Jul 2009
Posts: 279
Default

Los Alamos National Laboratory has been working on Thru the Earth Communications since 1996 with support from the Department of Energy initialy to communicate and locate trapped miners. They have developed a very mobile device that can send both video and data communications thru 300 feet of vertical rock or 550 feet horizontality thru rock and soil. This is all based on the micro chips found in cell phones.

An article is presented here http://www.afcea.org/signal/articles...437&zoneid=222

You will notice it works in pairs with a surface device and a subterranean reciever.

Here is the patent http://www.freepatentsonline.com/y2006/0148514.html

Lockheed Martin has also been working on devices as well http://www.mwrf.com/Article/ArticleID/22911/22911.html They have successfully communicated voice to a depth of 1550 feet with data beyond this.

Nikola Tesla was also working on this in 1915 in conjuntion with his world communications station.

Lets say TMP developed this earlier for communications with their boltholes and underground bases. A small reciever is placed near the surface above the bolthole that "listens" for coded signals from Prime Base and this device then transmits to the reciever in the bolthole thru the earth. VLF is still in use, but just at a very limited range and Prime Base doesn't need to errect large masts to communicate with the boltholes.
Reply With Quote
  #3  
Old 02-02-2011, 01:14 PM
nuke11 nuke11 is offline
Registered User
 
Join Date: Jul 2009
Posts: 279
Default

Here is a brochure on the Lockheed Martin TEC devices. As you can see it is not that large of a device.

http://www.lockheedmartin.com/data/a...icComm_Sys.pdf
Reply With Quote
  #4  
Old 02-06-2011, 08:06 PM
robj3 robj3 is offline
Some bloke
 
Join Date: Dec 2010
Location: Newcastle NSW
Posts: 51
Default

Thanks for the info, nuke11.

Having read these, you have a system that could link an above ground facility to an underground installation like a bolthole within a few hundred to 1500 feet. So we have a potential receiver setup for the bolthole end.

Hopefully there isn't too much attenuation by moisture laden or high clay content overburden.

http://www.lockheedmartin.com/data/a...roductcard.pdf
Has some more info including how big the equipment is.

It does not address the Prime Base-bolthole communication link.

Quote:
VLF is still in use, but just at a very limited range and Prime Base doesn't need to errect large masts to communicate with the boltholes.
Why use VLF for short-range transmissions (how far is this, anyway?)

I'll have to disagree here unless you can find a VLF transmitter array that doesn't involve big antennae. TACAMO aircraft obviously have portable equipment, but the multi-kilometer (mile) antenna is a problem.

Requiring multi-hundred metre (yard) length receiving antennae is also a pain in the butt.

What I was looking for was a single solution for Prime-bolthole and inter team communications.

I still think shortwave or meteor burst systems are the best way to provide this, but would appreciate any further information that could change my mind.
Reply With Quote
  #5  
Old 02-07-2011, 11:15 AM
nuke11 nuke11 is offline
Registered User
 
Join Date: Jul 2009
Posts: 279
Default

If you are looking for an all encumpassing solution that allows Prime to communicate with the BoltHoles, that is going to be a very tall order.

I would say it is going to be a combination of solutions that will allow one-way communications with the bolthole until the team is awake, then two-way communications can be established with the teams equipment in their vehicle.
Reply With Quote
  #6  
Old 02-13-2011, 11:14 PM
robj3 robj3 is offline
Some bloke
 
Join Date: Dec 2010
Location: Newcastle NSW
Posts: 51
Default

nuke11 wrote:
Quote:
If you are looking for an all encumpassing solution that allows Prime to communicate with the BoltHoles, that is going to be a very tall order.
I disagree.

What are the criteria for the solution?

- Concealable transmitter and receiver antennae/array
- Long transmitter range (for the Prime Base end) +/- relay stations
- Independence from geological formations (main problem with ELF transmitter)
- Relatively small size of receiver antenna (minimises the size of land parcel and amount of excavation required for bolthole)
- Relatively small transmitter power demand (ideally low [1-2 kilo]watts for portable [fusion powered?] units)
- Independence from satellites (vulnerable space infrastructure)
- Independence from ionospheric conditions (shortwave worst affected here, ELF/VLF not really affected, meteor burst in between)

The biggest problem with shortwave and meteor burst is the receiving antennae.
These will need to be fairly large (tens of yards/metres) if buried.
The other equipment is highly portable.

I think buried antennae will be required in any case, as a backup to a disguised above ground one.

There is an industry devoted to concealing cell phone towers:
http://www.utilitycamo.com/sites.html
http://weburbanist.com/2010/03/26/fa...ellular-sites/
http://news.cnet.com/Photos-Spot-the...3-5475371.html

As far as one-way communication (Prime-Bolthole) is concerned, a solution was suggested in my first post:

Quote:
A master station transmits a probe signal into the upper atmosphere. Remote stations wait to receive the probe signal reflected off a meteor trail. They then transmit a message back to the master station that a communication channel is open. The master then acknowledges the remote station and communications begin.

Another option is that the master repeatedly transmits to an array of remote stations. The remotes are in a receive mode only. Given enough time a channel will open to all the remotes.
This is based on info from Cohen et al's report (NTIA Report 89-241).

Quote:
I would say it is going to be a combination of solutions that will allow one-way communications with the bolthole until the team is awake, then two-way communications can be established with the teams equipment in their vehicle.
For the sake of redundancy you could have two different bands/formats e.g. SW/meteor burst. There may be some scope for a ground wave network, but an operational radius of 2,000km [for meteor burst] covers North America with only a few relay stations required.
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -6. The time now is 10:36 PM.


Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.