US20030143945A1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electromagnetic field communications system for wireless networks
Assignee: Individual
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Filing: 2003-02-04
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Granted: —
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Expires: 2023-02-04
Abstract
Abstract An Electromagnetic Field Communications System for Wireless Networks for producing an electromagnetic field within a structure is disclosed. The electromagnetic field is produced by using common conductive elements already present within virtually all pre-existing residential commercial, industrial buildings. These conductors, which may include electrical ground shields, wiring, pipes, sprinkler conduits or structural members, are excited with a signal, and become the cavity which contains the electromagnetic field. In preferred embodiments of the invention, signals are generated using the High Frequency, Very High Frequency and lower UHF bands (3 to 30, 30 to 300 and up to 400 MHz). The invention may be used to create a local area network inside the field and within the structure. Devices that include receivers tuned to the electromagnetic field may then be connected and networked. The system may be operated without causing interference to other conventional radio devices outside the structure in the HF band.
Inventors
- 👤 George Chadwick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:18
CPC Classifications
H; H01; H01Q; H01Q1/00; H01Q1/52; H01Q1/44; H01Q1/46; H01Q1/007; H01Q1/12; H01Q1/22; H01Q1/2208; H01Q1/526
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
76 words
1 . A method comprising the steps of: generating a radio frequency signal; feeding said frequency signal to a conductor; said conductor being a conductive array existing within a structure; creating a quasi-static non-propagating electromagnetic field within said structure, said electromagnetic field extending from said conductor in a manner such that said structure forms a cavity resonator; and using said electromagnetic field to convey said radio frequency signal to a receiver generally located within said structure.
Claim 2
Dependent Claim
76 words
1 . A method comprising the steps of: generating a radio frequency signal; feeding said frequency signal to a conductor; said conductor being a conductive array existing within a structure; creating a quasi-static non-propagating electromagnetic field within said structure, said electromagnetic field extending from said conductor in a manner such that said structure forms a cavity resonator; and using said electromagnetic field to convey said radio frequency signal to a receiver generally located within said structure.
Claim 3
Dependent Claim
23 words
2 . A method as recited in claim 1 , in which said radio frequency signal is generated using the High Frequency band.
Claim 4
Dependent Claim
24 words
3 . A method as recited in claim 1 , in which said radio frequency signal is generated using the Very High Frequency band.
Claim 5
Dependent Claim
28 words
4 . A method as recited in claim 1 , in which said radio frequency signal is generated using the low end of the Ultra High Frequency band.
Claim 6
Dependent Claim
42 words
5 . A method as recited in claim 1 , in which said radio frequency signal is generated using a frequency band which is characterized by a wavelength having a maximum dimension which is generally less than ten wavelengths in any dimension.
Claim 7
Dependent Claim
35 words
6 . A method as recited in claim 1 , in which said radio frequency signal is generated using a frequency band which does not generally cause interference outside said structure in the HF band.
Claim 8
Dependent Claim
26 words
7 . A method as recited in claim 1 , in which said radio frequency signal is fed to said conductor using a direct, hard-wired connection.
Claim 9
Dependent Claim
30 words
8 . A method as recited in claim 1 , in which said radio frequency signal is fed to said conductor by exciting said conductor with transmitted radio frequency energy.
Claim 10
Dependent Claim
18 words
9 . A method as recited in claim 1 , in which said conductor is an electrical wire.
Claim 11
Dependent Claim
18 words
10 . A method as recited in claim 1 , in which said conductor is a water pipe.
Claim 12
Dependent Claim
18 words
11 . A method as recited in claim 1 , in which said conductor is a structural member.
Claim 13
Dependent Claim
38 words
12 . A method as recited in claim 1 , comprising the additional steps of: allowing simultaneous operation in the HF, VHF and lower UHF band with multiple connections; and filtering said multiple connections to insure signal separation.
Claim 14
Dependent Claim
45 words
13 . A method as recited in claim 1 , comprising the additional steps of: installing said receiver by inserting a conventional power plug into a conventional electrical socket; and feeding said signal to said conductor through a third ground prong on said power plug.
Claim 15
Dependent Claim
71 words
14 . An electromagnetic field system, comprising: a structure including an electrically conductive grid array having a grid opening size; and means for generating a quasi-static non-propagating electromagnetic filed within said structure by feeding a frequency signal into said electrically conductive grid array; wherein the frequency of said frequency signal is selected such that the dimension of said grid opening size is small relative to the wavelength of said frequency signal.
Claim 16
Dependent Claim
71 words
14 . An electromagnetic field system, comprising: a structure including an electrically conductive grid array having a grid opening size; and means for generating a quasi-static non-propagating electromagnetic filed within said structure by feeding a frequency signal into said electrically conductive grid array; wherein the frequency of said frequency signal is selected such that the dimension of said grid opening size is small relative to the wavelength of said frequency signal.
Claim 17
Dependent Claim
34 words
15 . The electromagnetic field system of claim 14 , wherein the frequency of said frequency signal is selected such that the wavelength is greater than twice the dimension of said grid opening size.
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