Electromagnetic coupler system

• US 20040066326A1
• Filed: 10/02/2002
• Published: 04/08/2004
• Est. Priority Date: 10/02/2002
• Status: Active Grant

• Current Assignee: Guenther Knapp
• Original Assignee: Guenther Knapp
• Inventors: Knapp, Guenther
• Granted Patent: US 6,963,305 B2
• Time in Patent Office: Days
• US Class Current: 342/350
• CPC Class Codes: H01Q 1/1285 with capacitive feeding through the windscreen
• CPC Class Codes: H04W 52/0206 in access points, e.g. base stations access point devices per se H04W88/08
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 92/02 Inter-networking arrangements
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

This invention makes it possible to communicate through solid non-metallic walls or ceilings with low microwave power levels. RF beam forming couplers are driven by common LAN (Local Area Network) circuits.

For connection to a LAN segment at the other side of a wall or ceiling, transceiver 4 transmits data modulated microwave RF to coupler 6 through a directional step attenuator 10. The reduced signal is received by the coupler system at the other side with a power level low enough to eliminate wireless detection from the outside. However, the directional step attenuator on the receive side reduces the signal power only by an insignificant amount due to its low directional losses during receive signal flow. Each coupler'"'"'s geometry is minimizing the radiation exposed material volume by RF field concentration, therefore, enabling transmission through thick concrete walls at microwave frequencies without compromising privacy. When used as wireless access point, coupler transmits through a floor to wireless devices below. The preferred embodiment operates in the 5-GHz ISM band.

Claims

1. An electromagnetic coupler system for wired and wireless information networks to provide connectivity through walls and ceilings without their alteration, comprising:

a transceiver with data controller providing bridging of wired or wireless signals to modulated Rf frequencies;

an electromagnetic coupling device of predetermined design for transmission and reception of information modulated radio frequencies through walls and ceilings with low transmission power losses; and

a radio frequency conductive and reflective structure forming an electromagnetic low volume radiation field inside a wall or ceiling in interaction with a resonating means placed close to a wall or ceiling.

2. An electromagnetic coupler system according to claim 1 wherein:

a resonating means with said structure tuned to the radio frequencies of operation by their materials and geometrical features; and

a connecting means with impedance matching transmission line to the resonating means.

3. An electromagnetic coupler system according to claim 2 wherein:

a shielding means is included as part of said structure to reduce side lobe radiation and increase coupling efficiency.

4. An electromagnetic coupler system according to claim 3 wherein:

at least one provision for fastening the said coupling device to a wall or ceiling to expedite installation and add convenience to temporary network setups.

5. An electromagnetic coupler system according to claim 4 wherein:

one or more directional attenuators are placed into the signal path of said bridging means and said electromagnetic coupling device to maximize the received signal power and minimize the transmitted signal power, comprising;

one or more radio frequency isolating means with low forward signal power loses and high isolation attenuation; and

a connecting means for connection to said bridging means and said electromagnetic coupling device or for serial connection of more than one said isolating means.

8. An electromagnetic coupler system according to claim 4 wherein:

a step directional attenuator according to claim 6 or 7 is placed into the RF signal path of said bridging means and said electromagnetic coupling device to maximize the received signal power and minimize the transmitted signal power over wide ranges of wall or ceiling thickness and material types.

9. An electromagnetic coupler system according to claim 5, 8, 11 or 12 is placed at a wall or ceiling wherein:

a second said coupler system is placed at the opposite of said wall or said ceiling for transmission to and from a network segment at the opposite side of said wall or said ceiling, therefore providing interference free communication in privacy through thick walls with materials of high radio frequency power losses because of the small volume of material exposed to electromagnetic radiation.

10. An electromagnetic coupler system according to claims 2, 3, 11 or 12 wherein:

a plurality of antenna connections are provided by said bridging means; and

a plurality of said electromagnetic coupling devices placed at a wall or on a floor are connected to said plurality of antenna connections for wireless communication to wireless devices behind a wall or below a floor, therefore avoiding installation of wall and ceiling antennas.

11. An electromagnetic coupler system according to claim 4 wherein:

one or more attenuator means are placed into the RF path between said bridging means and said electromagnetic coupling device and said one or more attenuator means are connected or disconnected by switching means that are synchronized with Tx/Rx control signals from said bridging means.

12. An electromagnetic coupler system according to claim 11 wherein:

said one or more attenuator means are replaced by a step attenuator means with switching means activated through a controlling means with a manually operated attenuation selecting means or by automatic attenuation control signals from said bridging means.

6. A radio frequency directional step attenuator where attenuation is determined by the direction of signal flow, comprising:

a plurality of said isolating means with impedance matched ports for forward and backward signal flow; and

a plurality of manually operated low cross talk switching means are providing impedance matched bidrectional operation of engaged said isolating means.

7. A radio frequency directional step attenuator according to claim 6 wherein said switching means are activated through a logic controller means by a manually operated attenuation selecting means or by automatic attenuation control signals from a bridging means.