Telecommunications – Transmitter and receiver at separate stations – Short range rf communication
Reexamination Certificate
1999-12-20
2001-04-17
Tsang, Fan (Department: 2746)
Telecommunications
Transmitter and receiver at separate stations
Short range rf communication
C455S106000, C455S276100, C340S572500, C340S572700, C340S010100, C340S010300
Reexamination Certificate
active
06219530
ABSTRACT:
The invention relates to a communication station which is arranged for contactless communication with at least one transponder and is provided with a transmission coil configuration with an active, first transmission coil circuit which includes a first transmission coil wherethrough a coil current can be driven, and with a passive, second transmission coil circuit which includes a second transmission coil which is oriented essentially parallel to the first transmission coil, is arranged opposite the first transmission coil and is inductively coupled to the first transmission coil, a coil current which has been phase shifted essentially 90° with respect to the coil current that can be driven through the first transmission coil being drivable through said second transmission coil as a result of the inductive coupling to the first transmission coil, and is also provided with transmission means which are arranged to generate a transmission signal and are connected to the first transmission coil circuit, and also with first receiving means which are connected to the first transmission coil circuit and are arranged to receive a first receiving signal obtained by means of the first transmission coil circuit, and also with evaluation means which are connected to the first receiving means and whereby received data, corresponding to the first receiving signal received by the first receiving means, can be evaluated.
The invention also relates to a transmission coil configuration which is intended for use in a communication station for contactless communication with at least one transponder and is provided with an active, first transmission coil circuit which includes a first transmission coil wherethrough a coil current can be driven, and with a passive, second transmission coil circuit which includes a second transmission coil which is oriented essentially parallel to the first transmission coil, is arranged opposite the first transmission coil and is inductively coupled to the first transmission coil, a coil current which has been phase shifted essentially 90° with respect to the coil current that can be driven through the first transmission coil being drivable through said second transmission coil as a result of the inductive coupling to the first transmission coil.
A communication station of the kind set forth in the first paragraph and a transmission coil configuration of the kind set forth in the second paragraph are already commercially available and widely used in practice and hence are known. For such a communication station and such a transmission coil configuration, reference can be made, for example, to the patent document WO 97/49076 A1.
The aim in such communication stations and transmission coil configuration is always to achieve an as high as possible recognition reliability, i.e. to recognize any transponder entering the communication range of such a communication station and such a transmission coil configuration with a high degree of reliability, and also to achieve an as high as possible communication dependability, i.e. to communicate with such a transponder with a high degree of dependability. Even though in many cases a high degree of recognition reliability and communication dependability are achieved by means of the known communication system and the known transmission coil configuration, it has been found that the recognition reliability and the communication dependability that can be achieved for more critical applications are not satisfactory.
It is an object of the invention to improve a communication system of the kind set forth in the first paragraph and a transmission coil configuration of the kind set forth in the second paragraph and to realize an improved communication system and an improved transmission coil configuration which offer a recognition reliability and a communication dependability which are distinctly higher than those of the known communication station and the known transmission coil configuration.
In order to achieve the described object a communication system of the kind set forth in the first paragraph according to the invention is characterized in that the transmission coil configuration is additionally provided with an active, third transmission coil circuit which includes a third transmission coil which is oriented transversely of the first transmission coil, is arranged so as to be offset relative to the first transmission coil, and through which there can be driven a coil current which has one of two phase angles relative to the coil current that can be driven through the first transmission coil, the two phase angles being 0° or 180°, and that the transmission means and the first receiving means are also connected to the third transmission coil circuit.
In order to achieve the described object a transmission coil configuration of the kind set forth in the second paragraph according to the invention is characterized in that the transmission coil configuration is additionally provided with an active, third transmission coil circuit which includes a third transmission coil which is oriented transversely of the first transmission coil, is arranged so as to be offset relative to the first transmission coil, and through which there can be driven a coil current which has one of two phase angles relative to the coil current that can be driven through the first transmission coil, the two phase angles being 0° or 180°.
Taking the steps according to the invention, an additional magnetic field configuration is created by means of the third transmission coil, in co-operation with the first transmission coil and the second transmission coil, said additional magnetic field configuration offering an essentially higher recognition reliability and an essentially higher communication dependability in comparison with the art known thus far.
A further, significant contribution to said high recognition reliability and said high communication dependability is realized by taking the steps disclosed in the claims
2
and
13
.
The means for coupling in a communication station according to the invention and in a transmission coil configuration according to the invention may be formed by a flat, fourth transmission coil which is arranged opposite the second transmission coil. It has been found to be advantageous, however, to take the steps disclosed in the claims
3
and
14
, because a particularly tight coupling can thus be created and hence a second receiving signal with a satisfactorily high level is obtained.
With a view to achieving an as simple as possible construction of the transmission coils, it has been found that it is very advantageous to take the steps disclosed in the claims
5
and
6
or the claims
16
and
17
.
With a view to achieving a high degree of recognition reliability and communication dependability, it has been found that the steps disclosed in the claims
7
and
18
are particularly advantageous.
With a view to achieving an as simple as possible electrical construction, it has been found that the steps disclosed in the claims
8
and
9
or the claims
19
and
20
are very advantageous.
A construction which is particularly advantageous in practice is characterized by the steps disclosed in the claims
10
and
11
or the claims
21
and
22
. In this context it has been found that it is particularly advantageous to take the steps according to the invention for conveyor belts for luggage at airports or for conveyor belts for products in factories.
The foregoing aspects and further aspects of the invention will become apparent from and will be elucidated with reference to the following embodiment.
The invention will be described in detail hereinafter on the basis of an embodiment which is shown in the drawings, however, without the invention being restricted thereto.
REFERENCES:
patent: 5258766 (1993-11-01), Murdoch
patent: 5594448 (1997-01-01), D'Hont
patent: WO9749076 (1997-12-01), None
Milord Marceau
Tsang Fan
U.S. Philips Corporation
LandOfFree
Transponder communication station provided with a... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Transponder communication station provided with a..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Transponder communication station provided with a... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2504916