WO2001024407A1

WO2001024407A1 - Method and apparatus for providing a passive wireless network across divided spaces

Info

Publication number: WO2001024407A1
Application number: PCT/US2000/024870
Authority: WO
Inventors: Kenichi Kawasaki; David Alan Desch
Original assignee: Sony Electronics, Inc.
Priority date: 1999-09-29
Filing date: 2000-09-11
Publication date: 2001-04-05
Also published as: AU7368500A; WO2001024407A9

Abstract

A passive repeater allows wirelessly communicating electronic devices to be networked despite being separated by barriers or obstructions which would otherwise attenuate the wireless signaling between the electronic devices. First and second antennae are connected by a waveguide which can be disposed through or around the barrier or obstruction between electronic devices. The antenna at each end of the waveguide collect or retransmit in a multidirectional manner wireless signaling being broadcast. This allows the repeater to communicate the wireless signaling across the barrier between communicating electronic devices without wireless signal attenuation.

Description

TITLE OF THE INVENTION

Method and Apparatus for Providing a Passive Wireless Network Across Divided Spaces

FIELD OF THE INVENTION

The present invention relates to the field of wireless local area networks (LANs). Specifically the present invention relates to a passive coupler/repeater for wirelessly interconnecting electronic devices that are spread among divided spaces in a local area network.

BACKGROUND OF THE INVENTION

In modern technology, the ability to communicate data wirelessly between electronic devices is extremely useful. For example, remote control units can be used to wirelessly control television sets, VCR's, home stereos and other electronic equipment. Additionally, cordless and wireless telephones can be used to conduct telephone calls from almost any location in a house or service area. Information stored in a personal digital assistant (PDA) may be communicated to a larger computer or another computerized device through wireless signaling .

There are several different formats for wireless data communication. For example, infrared signals carry information between electronic devices using optical signaling in the infrared range of the electromagnetic spectrum. Such infrared signaling is commonly used between remote control devices and, for example, television sets. Alternatively, radio frequency signaling is commonly used to convey information wirelessly between, for example, a wireless telephone handset and the wireless communication system that supports that wireless telephone handset. In the future, there will be more and more wireless communication between electronic devices. For example, an emerging technology is to wirelessly network electronic devices among the rooms of a home or office. To prevent interference between such a wireless network and existing wireless signaling, the format for such networking is typically high frequency radio waves in the gigahertz range. The wavelength of such RF signals is measured in millimeters. Therefore, such signals are commonly referred to as millimeter waves.

However, a problem arises with the use of such high frequency radio waves in that these waves are significantly attenuated by physical barriers such as walls or doors. Therefore, it is difficult to transmit millimeter waves between wirelessly networked electronic devices which do not have a clear line of site to each other or which are separated by walls or other dividers between spaces.

Consequently, there is a need in the art for a method and apparatus which allows the creation of a wireless network using, for example, millimeter radio waves or other types of wireless signaling which are attenuated by obstacles .

SUMMARY OF THE INVENTION

It is an object of the present invention to meet the above-described needs and others. Specifically, it is an object of the present invention to provide a method and apparatus that allow electronic devices to be wirelessly networked using, for example, millimeter radio waves or other types of wireless signaling which are attenuated by obstacles, despite the presence of such obstacles between the networked devices.

Additional objects, advantages and novel features of the invention will be set forth in the description which follows or may be learned by those skilled in the art through reading these materials or practicing the invention. The objects and advantages of the invention may be achieved through the means recited in the attached claims.

To achieve these stated and other objects, the present invention may be embodied and described as a passive repeater for wireless signaling including a first passive antenna; a second passive antenna; and a passive waveguide connecting the first and the second antenna. The waveguide is used to conduct wireless signaling received by either of the antennae around or through obstructions or partitions that would otherwise attenuate the wireless signal. For example, the waveguide may be angled to accommodate an edge of a partition, the first and second antennas being disposed on opposite sides of the partition. Alternatively, the waveguide may be disposed through an opening between opposite sides of the partition. Preferably, the waveguide, or its casing, forms a bias between the first and second antennae causing the first and second antennae to grip opposite sides of a partition around which they are placed. Alternatively, a clamp or other mounting device could be provided on the repeater for mounting it in place.

For flexibility, the waveguide may be articulating or bendable such that the waveguide can be shaped to provide a desired angle between the first and second antennae. Once bent, the waveguide should hold that shape to maintain the desired angle between the first and second antennae.

If optical signaling is desired, the first and second antennas each incorporate a lens. While the waveguide is an optical waveguide. Alternatively, the wireless signaling may be radio frequency signaling, particularly millimeter wave signaling. In which case, the antenna and waveguide are adapted for transmitting radio frequency signals.

The present invention also encompasses a method of wirelessly networking electronic devices which are separated by partitions or obstructions that tend to attenuate wireless signals within a wireless network. The method includes transmitting wireless signals between networked electronic devices with at least one passive repeater for transmitting the wireless signals through or around the partition or obstruction.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate the present invention and are a part of the specification. Together with the following description, the drawings demonstrate and explain the principles of the present invention.

Fig. 1A is a cross-sectional view of a first embodiment of a passive wireless signal repeater according to the present invention.

Fig. IB is a perspective view of the repeater of Fig. 1A as mounted in a space divider.

Fig. 2A is a cross-sectional view of a second embodiment of a passive wireless signal repeater according to the present invention.

Fig. 2B is a perspective view of the repeater of Fig. 2A as mounted in a space divider.

Fig. 3A is a cross-sectional view of a third embodiment of a passive wireless signal repeater according to the present invention.

Fig. 3B is a perspective view of the repeater of Fig. 3A as mounted in a space divider.

Fig. 4 is a top view of a repeater according to the present invention being used in an office environment. Fig. 5 is a diagram of an office LAN that utilizes several different embodiments of repeaters according to the present invention in a single network.

Fig. 6 illustrates a fourth embodiment of the repeater of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Using the drawings, the preferred embodiments of the present invention will now be explained. Stated in broad principle, the present invention involves the use of passive repeaters or couplers to redirect wireless signaling between electronic devices around or through barriers between spaces. As used herein, the term passive means that no electrical power or power source is provided for any of the components of the coupler/repeater. The material and construction of the coupler/repeater will depend upon the type of wireless signaling used. Fig. 1A illustrates a first embodiment of the present invention. As shown in Fig. 1A, a repeater according to the present invention is comprised of an antenna (101) and an antenna (102) on opposite sides of a wall (103) . An opening (104) within the wall enclosed a waveguide (105) between the first and second antennae (101 and 102) . In this way, the repeater (100) guides wireless signaling (106) through the wall.

Antenna (101), for example, receives wireless signaling (106), directs that signaling to the waveguide (105) and transmits the signaling through the waveguide (105) . Then, antenna (102) receives the signaling through the waveguide (105) and reemits the wireless signaling (106A) . In this way, electronic devices on opposite sides of the wall (103) can communicate wirelessly without having a direct line of sight to each other and without the wireless signals used being attenuated by the wall (103) or other obstruction or space divider.

Fig. IB illustrates a perspective view of the passive repeater (101) of the present invention that allows communication between room A and room B.

Various embodiments for the passive repeater (100) will be required depending on the type of wireless signaling being used. For example, if the wireless signaling (106) is an optical or infrared signal, the antenna (101) will be, for example, a lens which collects the optical signaling and focuses it into the waveguide (105). Waveguide (105) will be an optical waveguide, for example a fiber optic cable. The lens of the antenna (102) will multi-directionally emit the optical signal after it has passed through the waveguide (105) .

It will be understood that the lenses of both antennas (101 and 102) can both collect and emit optical signaling as described. In this way optical signaling which could not otherwise pass the wall (103) can be communicated between electronic devices on opposite sides of the wall (103) in either direction.

Alternatively, if the wireless signaling being used is millimeter radio frequency waves, the antennas (101 and 102) will be radio frequency antennae and the waveguide (105) will be a guide for transmitting and redirecting, without attenuation, the radio frequency signals received by the antennae (101 or 102) . The antennae (101 and 102) will also each be capable of being excited by, and therefore re-transmitting, in a multi-directional manner the radio frequency waves in the millimeter range which have been transmitted through the waveguide (105) . In this way electronic devices on opposite sides of the wall (103) can communicate wirelessly using millimeter radio frequency waves. Using millimeter radio frequency wireless signaling, the waveguide (105) may be constructed with several different designs an configurations. For example, a millimeter radio frequency waveguide may be a hollow tube made of a conductive material or having a conductive material coated on the inside thereof. The tube of a millimeter radio frequency waveguide, according to the present invention preferably has a circular or rectangular cross-section. The dimensions of the tube of a millimeter radio frequency waveguide are important. The dimensions define the mode for the millimeter radio wave propagation. If there are multiple modes of propagation in the waveguide, it is difficult to control the propagation and the resulting re-transmission from the antenna at the other end of the guide.

For example, a round waveguide tube for millimeter radio frequency waves, with a circular cross-section, preferably has a radius between 1.790 mm and 1.4 mm, and more preferably has a radius of 1.583 mm. For such a guide, the TEn Mode cutoff frequency is 55.3 GHz; the TMoi Mode cutoff frequency is 72.3 GHz and the TE₀ι Mode cutoff frequency is 115 GHz. The attenuation is 1.967 dB/m at 66.41 GHz. If a rectangular tube is used as the millimeter radio frequency waveguide, the guide preferably has interior dimensions of 1.8796 mm in height and 3.7592 mm in width. For millimeter waves with a frequency between 50 and 75 GHz in such a guide, the TEio mode cutoff frequency is 39.863 GHz and the attenuation is 1.75 dB/m to 1.28 dB/m.

Alternatively, a millimeter radio frequency waveguide could be a dielectric waveguide which uses a relatively high dielectric constant material to contain the millimeter-wave energy. It would also be possible to form a millimeter radio frequency waveguide using a co-axial cable. However, it would be difficult to make a co-axial cable with the appropriate dimensions to accommodate millimeter radio waves. Moreover, the co- axial cable would be prone to significant attenuation of the signal. Finally, a microstrip line, stripline, coplanar waveguide or slot line could also be used as the millimeter radio frequency waveguide. However, these types of waveguides are, again, subject to significant attenuation.

As a third alternative, the wireless signaling (106) could be an ultrasonic signal. In which case, the antennae (101 and 102) would be an ultrasonic "ear" and the waveguide (105) a sound passage for transmitting the ultrasonic signal without attenuation through the wall (103) .

Fig. 2A, illustrates a second embodiment of the present invention. As shown in Fig. 2A a waveguide (205) in the passive repeater (201) of the present invention need not be mounted through an opening in the wall (103) or other barrier between communicating electronic devices. As shown in Fig. 2A the waveguide (205) between the antennas (101 and 102) can be routed around an edge of the wall or door (203) which is the barrier between wirelessly communicating electronic devices in the local area network of the present invention .

As shown in Fig. 2B, in this embodiment, antennae (101 and 102) are mounted to opposite sides of a wall, door or other divider (203) adjacent to the edge of that divider (203). The waveguide (205) is then routed around the edge of the divider (203) rather than through an opening in that divider wall as illustrated in Fig. 1A. Fig.-3A, illustrates a third embodiment of the present invention. In this embodiment of the present invention the repeater (300) is not permanently mounted to the wall or barrier (303) that separates wirelessly communicating electronic devices . Rather, the repeater (300) of this embodiment includes a waveguide (305) which communicates between the first and second antennas (101 and 102), but which also provides a means by which the repeater (300) can be clipped temporarily to the wall, door or barrier (303) .

Similar to the waveguide (205) in Figs. 2A and 2B, the waveguide (305) in Fig. 3A and Fig. 3B is disposed around an edge of the wall, door or other space divider (303) rather than through an opening in the divider wall (303) . However, the repeater (300) is adapted to be slipped on and off the edge of the barrier (303) or repositioned along the edge of the barrier (303) as needed. Additionally, the waveguide (305) may be made of, or incased in, a material which has a resiliency or spring constant which provides a bias which biases the antennas (101 and 102) toward each other. In this way, the antennas (101 and 102) are pulled apart and placed on opposite sides of the barrier (303) . As a result, the tension created between the antennas (101 and 102) by the material or casing of the waveguide (305) tends to hold the antennas (101 and 102), and thus the repeater (300), in place on the barrier (303) .

Fig. 4 illustrates the use of a repeater (400) according to the present invention in the environment of partitioned office spaces. The repeater (400) illustrated in Fig. 4 may be any of the repeaters previously discussed as embodiments of the present invention, for example repeater (100) of Fig. 1A, repeater (201) of Fig. 2A or repeater (300) of Fig. 3A. As shown in Fig. 4, a room partition (403) is provided to separate the office space of a user (402) from other space in the room. The repeater (400) is provided on, around or through the room partition (403) . In this way, electronic devices within the user's (402) partition (403) can wirelessly communicate with electronic devices outside the room partition (403) using optical signals, millimeter radio frequency waves or other wireless signaling formats which would otherwise be attenuated by the room partition (403) . Fig. 6 illustrates a third embodiment of the present invention. The embodiment of Fig. 6 is similar to the embodiments previously discussed in that the antennae (101 and 102) are separated by a waveguide (605) for communicating a wireless signal (106) between the two antennae (101 and 102) to avoid any obstruction or obstacle which would otherwise attenuate the wireless signaling (106). However, the waveguide (605) is flexible or articulating so that the user may define the angle between antennas (101 and 102). The waveguide (605) is made of a material, or is incased in a material, that will hold its shape once deformed by the user to a desired angle. In this way wireless signaling (106) can be redirected at any angle necessary to avoid an obstruction or to create a direct line of site between wirelessly communicating electronic devices.

Fig. 5 illustrates various uses of the present invention in several different embodiments within an office space. As shown in Fig. 5 a user (503) is working with a personal digital assistant or other computerized device (501) which needs to communicate wirelessly with another electronic device, for example a printer (502), which is separated from the electronic device (501) by a partition (511) . In order to allow this communication, various different configurations of repeaters according to the present invention can be used. For example as shown in Fig. 5 a repeater (601) with a flexible waveguide according to the embodiment of Fig. 6 can be mounted above the user so as to direct wireless signaling from the computerized device (501) toward a repeater (510) mounted on the ceiling of the room. This wireless path is illustrated in Fig. 5 as (106B) .

The repeater (510) which can be constructed according to any of the various embodiments of the present invention particularly that of Fig. 6 redirects the wireless signaling (106B) to a second wall mounted repeater (510) shown on the right hand side of Fig. 5 this repeater in turn transmits the wireless signal (106B) to the printer (502) or other electronic device on the far side of the partition (511) .

Alternatively as also shown in Fig. 5, wireless signaling from the computerized device (501) may follow path (106C) to a repeater (300) which is of either the clip type of Fig. 3 or the edge mounted type of Fig. 2. This repeater transmits the wireless signal path (106C) around the partition (511) as shown in Fig. 5. An additional repeater (300) is required in signal path (106C) to redirect the wireless signal around an obstacle (512) above the printer (502) or other electronic device so that the wireless signaling (106C) can reach the second electronic device (502).

Therefore, as shown in Fig. 5, the various repeaters of the present invention can be used in several different types of combinations in any given situation, as will be clear to those of ordinary skill in this art, to create an appropriate wireless signal path between electronic devices which are otherwise separated by a wall or partition that would attenuate the wireless signaling. In this way the repeater of the present invention and the method which corresponds therewith can allow for more efficient communication between electronic devices which are separated by partitions, walls or barriers in divided space. This will allow those of skill in the art to create local area networks among all sorts of wirelessly communicating electronic devices which would not have been possible without the passive repeater of the present invention. An additional advantage of the present invention is the fact that the wireless repeater is in fact passive and does not require any power source. This allows the repeater of the present invention to be implemented cheaply and at however many points necessary to provide appropriate wireless signaling between network devices. The preceding description has been presented only to illustrate and describe the invention. It is not intended to be exhaustive or to limit the invention to any precise form disclosed. Many modifications and variations are possible in light of the above teaching. The preferred embodiment was chosen and described in order to best explain the principles of the invention and its practical application. The preceding description is intended to enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims .

Claims

WHAT IS CLAIMED IS:

1. A passive repeater for wireless signaling comprising : a first passive antenna; a second passive antenna; and a passive waveguide connecting said first and said second antenna.

2. The repeater of claim 1, wherein said waveguide is angled to accommodate an edge of a partition, said first and second antennas being disposed on opposite sides of said partition.

3. The repeater of claim 1, wherein said waveguide forms a bias between said first and second antennae causing said first and second antennae to grip opposite sides of a partition around which they are placed.

4. The repeater of claim 1, wherein said waveguide is articulating such that the waveguide is bendable to provide a desired angle between said first and second antennae and, once bent, will hold that shape to maintain said desired angle between said first and second antennae.

5. The repeater of claim 1, wherein said wireless signaling is optical signaling and said first and second antennas each incorporate a lens.

6. The repeater of claim 1, wherein said wireless signaling is radio frequency signaling and said waveguide is a radio frequency waveguide.

7. The repeater of claim 6, wherein said radio frequency signaling is millimeter wave signaling.

8. A method of wirelessly networking electronic devices which are separated by partitions or obstructions which tend to attenuate wireless signals within a wireless network, the method comprising transmitting wireless signals between networked electronic devices with at least one passive repeater for transmitting said wireless signals through or around said partition or obstruction.

9. The method of claim 8, wherein said network is located between rooms or across space partitions in a place of business.

10. The method of claim 8, wherein said network is located between rooms in a home.

11. The method of claim 8, wherein said passive repeater comprises: a first passive antenna; a second passive antenna; and a passive waveguide connecting said first and said second antennae.

12. The method of claim 11, further comprising disposing said waveguide in an opening through said partition or obstruction, with said first and second antennae being located on opposite sides of said partition or obstruction.

13. The method of claim 11, further comprising bending said waveguide around an edge of said partition or obstruction, said first and second antennas being disposed on opposite sides of said partition or obstruction.

14. The method of claim 11, further comprising forming a bias between said first and second antennae causing said first and second antennae to grip opposite sides of said partition or obstacle around which they are placed.

15. The method of claim 11, further comprising articulating said waveguide which is flexible to provide a desired angle between said first and second antennae.

16. The method of claim 10, wherein said wireless signaling is optical signaling.

17. The method of claim 8, wherein said wireless signaling is radio frequency signaling.

18. The method of claim 8, wherein said radio frequency signaling is millimeter wave signaling.

19. A passive repeater for wireless signaling comprising : a first passive antenna means; a second passive antenna means; and a passive waveguide means connecting said first and said second antenna means.

20. The repeater of claim 19, wherein said waveguide means is angled to accommodate an edge of a partition, said first and second antenna means being disposed on opposite sides of said partition.

21. The repeater of claim 19, further comprising bias means for biasing portions of said passive repeater causing said repeater to grip opposite sides of a partition on which said passive repeater is placed.

22. The repeater of claim 1, wherein said waveguide means is articulating such that the waveguide means is bendable to provide a desired angle between said first and second antenna means and, once bent, will hold that shape to maintain said desired angle between said first and second antenna means.