Antenna port identification for a wireless communication node TECHNICAL FIELD

The present invention relates to a wireless communication node comprising at least one transceiver arrangement and at least one antenna system. Each transceiver arrangement comprises at least one signal port, and each antenna system comprises at least one antenna port. Said transceiver arrangement is connected to said antenna system by means of at least one radio frequency (RF) feeder cable running between corresponding ports. Each transceiver arrangement comprises a signal processing unit, and each antenna system comprises at least one antenna arrangement. Each antenna arrangement is connected to at least one corresponding antenna port, and each RF feeder cable is arranged to transfer RF signals between a corresponding signal processing unit and antenna arrangement via a corresponding signal port and antenna port. The present invention also relates to an antenna system comprising at least one antenna port arranged to be connected to a transceiver arrangement by means of at least one corresponding radio frequency (RF) feeder cable.

BACKGROUND

As radio networks evolve with smaller inter-site distances, higher order modulations, antennas arranged for MIMO (Multiple Input Multiple Output), beamforming etc., base station transceivers need to interface many more antenna variants with one or several antenna ports. A base station need to have information regarding antenna properties for each connected antenna port to secure that signal processing is optimized for the applied antenna variant. Such antenna properties may include antenna port identification and type of connected antenna. Different types of antennas may be single column array antennas, multi-column array antennas and/or single antenna elements. It is also desired to be able to monitor antenna connection status to secure that each antenna and its antenna ports are correctly connected to RF branches of the base station. Today, a base station is often pre-programmed with information regarding the antenna ports that it is intended to be connected to. In order to facilitate correct physical connections, antenna connectors may for example be color-coded. However, this still leaves a possibility for error, and lacks versatility for an installation that deviates from the pre-programmed.

In view of the above, it is desirable to provide a wireless communication node and an antenna system where a base station is enabled to acquire knowledge about the properties of the antenna ports that it is connected to in a more secure and versatile manner than has been the case previously.

SUMMARY

It is an object of the present invention to provide a wireless communication node and an antenna system where a base station is enabled to acquire knowledge about the properties of the antenna ports that it is connected to in a more secure and versatile manner than has been the case previously.

Said object is obtained by means of a wireless communication node comprising at least one transceiver arrangement and at least one antenna system. Each transceiver arrangement comprises at least one signal port, and each antenna system comprises at least one antenna port. Said transceiver arrangement is connected to said antenna system by means of at least one radio frequency, RF, feeder cable running between corresponding ports. Each transceiver arrangement comprises a signal processing unit, and each antenna system comprises at least one antenna arrangement. Each antenna arrangement is connected to at least one corresponding antenna port, and each RF feeder cable is arranged to transfer RF signals between a corresponding signal processing unit and a corresponding antenna arrangement via a corresponding signal port and a corresponding antenna port. Each transceiver arrangement comprises an interrogator arrangement, and each antenna system comprises at least one communication device. Each communication device is electrically connected to a certain corresponding antenna port by means of a corresponding electrical antenna port connection. Said interrogator arrangement is at least electrically connectable to at least one signal port, and is arranged to transfer an interrogation signal to a certain corresponding communication device via the corresponding signal port, the corresponding RF feeder cable and the corresponding antenna port. Each communication device is arranged to transfer a reply signal, comprising certain data, to said interrogator arrangement via the corresponding RF feeder cable. The creation and transmission of each reply signal is powered by energy comprised in each received interrogation signal.

Said object is also obtained by means of an antenna system comprising at least one antenna port arranged to be connected to a transceiver arrangement by means of at least one corresponding radio frequency (RF) feeder cable.

The antenna system comprises at least one communication device, where each communication device is electrically connected to a certain corresponding antenna port by means of a corresponding electrical antenna port connection. Each communication device is arranged to transfer a reply signal via said antenna port, the reply signal comprising certain data and being transferred in reply to an interrogation signal received via said antenna port. The creation and transmission of each reply signal is powered by energy comprised in each received interrogation signal. According to an example, each interrogator arrangement comprises at least two interrogator devices, where each is electrically connected to a certain corresponding signal port by means of a corresponding electrical signal port connection. Each interrogator device is arranged to transfer an interrogation signal to a corresponding communication device, and to receive a reply signal from said communication device.

According to another example, each interrogator arrangement comprises one interrogator device and a switch arrangement. Each switch arrangement is arranged to connect the corresponding interrogator device to any one of at least two signal ports in the corresponding transceiver arrangement via a corresponding electrical signal port connection.

According to another example, each electrical antenna port connection and each electrical signal port connection comprises a corresponding signal filter arranged for separating RF signals from interrogation and reply signals.

According to another example, each communication device is constituted by a radio- frequency identification (RFID) device.

According to another example, each communication device and/or interrogator arrangement is electrically connected to the corresponding antenna port and/or the corresponding signal ports by means of electrical coupling. Other examples are disclosed in the dependent claims.

A number of advantages are obtained by means of the present invention. Mainly, communication devices such as RFID devices are cheap, easy to produce, reliable, durable and can be connected to each individual port even for large antenna constellations without incurring significant costs and/or logistics problems.

The communication between the interrogator devices and the respective communication device is accomplished over each individual RF feeder cable, which makes it possible to have full control of all antenna ports and how they are interconnected with the signal ports of the wireless communication node.

The acquired information enables the wireless communication node to:

- Reduce need for manual definition of how the system is configured

- Tell operators if a configuration and/or connection is incorrect.

- Optimize the usage of the antenna systems based on their properties.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described more in detail with reference to the appended drawings, where: Figure 1 schematically shows a wireless communication node;

Figure 2 schematically shows a diagram of a first example of the wireless communication node;

Figure 3 schematically shows a diagram of a second example of the wireless communication node; Figure 4 schematically shows a diagram of an example of an electrical antenna port connection; and

Figure 5 schematically shows a diagram of an example of an electrical signal port connection.

DETAILED DESCRIPTION

With reference to Figure 1 , there is a node 1 in a wireless communication system 58; a wireless communication node 1 . With reference to Figure 2, schematically showing a diagram of a first example of the wireless communication node 1 , the wireless communication node 1 comprises a first transceiver arrangement 2 and a second transceiver arrangement 3. The node further comprises a first antenna system 4 and a second antenna system 5.

The first transceiver arrangement 2 comprises a first signal port 6, a second signal port 7 and a third signal port 8, and the second transceiver arrangement 3 comprises a fourth signal port 9 and a fifth signal port 10. In a similar manner, the first antenna system 4 comprises a first antenna port 1 1 and a second antenna port 12, and the second antenna system 5 comprises a third antenna port 13, a fourth antenna port 14 and a fifth antenna port 15.

The first transceiver arrangement 2 is connected to the first antenna system 4 by means of a first radio frequency (RF) feeder cable 16 running between the first signal port 6 and the first antenna port 1 1 , and to the second antenna system 5 by means of a second RF feeder cable 17 running between the second signal port 7 and the fourth antenna port 14, and by means of a third RF feeder cable 18 running between the third signal port 8 and the fifth antenna port 15.

The second transceiver arrangement 3 is connected to the first antenna system 4 by means of a fourth RF feeder cable 19 running between the fourth signal port 9 and the second antenna port 12, and to the second antenna system 5 by means of a fifth RF feeder cable 20 running between the fifth signal port 10 and the third antenna port 13. Furthermore, the first antenna system 4 comprises a first antenna arrangement 25 and a second antenna arrangement 26, and the second antenna system 5 comprises a third antenna arrangement 27. Furthermore, the first transceiver arrangement 4 comprises a first signal processing unit 21 and the second transceiver arrangement 5 comprises a second signal processing unit 22.

The first antenna arrangement 25 is connected to the first antenna port 1 1 , the second antenna arrangement 26 is connected to the second antenna port 12. The third antenna arrangement 27 is connected to the third antenna port 13, the fourth antenna port 14 and the fifth antenna port 15. Correspondingly, the first signal processing unit 21 is connected to the first signal port 6, the second signal port 7 and the third signal port 8, and the second signal processing unit 22 is connected to the fourth signal port 9 and the fifth signal port 10.

The RF feeder cables 16, 17, 18, 19, 20 are then arranged to transfer RF signals between the signal processing units 21 , 22 and the antenna arrangements 25, 26; 27 via the signal ports 6, 7, 8; 9, 10 and the antenna ports 1 1 , 12; 13, 14, 15.

According to the present invention, the first transceiver arrangement 2 comprises a first interrogator arrangement 23, and the second transceiver arrangement 3 comprises a second interrogator arrangement 24.

Furthermore, the first antenna system 4 comprises a first communication device 28 electrically connected to the first antenna port 1 1 by means of a first electrical antenna port connection 42, and a second communication device 29 electrically connected to the second antenna port 12 by means of a second electrical antenna port connection 43. Furthermore, the second antenna system 5 comprises a third communication device 30 electrically connected to the third antenna port 13 by means of a third electrical antenna port connection 44, a fourth communication device 31 electrically connected to the fourth antenna port 14 by means of a fourth electrical antenna port connection 45, and a fifth communication device 32 electrically connected to the fifth antenna port 15 by means of a fifth electrical antenna port connection 46. Correspondingly, the first interrogator arrangement 23 comprises a first interrogator device 33 electrically connected to the first signal port 6 by means of a first electrical signal port connection 47, a second interrogator device 34 electrically connected to the second signal port 7 by means of a second electrical signal port connection 48, and a third interrogator device 35 electrically connected to the third signal port 8 by means of a third electrical signal port connection 49. Furthermore the second interrogator arrangement 24 comprises a fourth interrogator device 36 electrically connected to the fourth signal port 9 by means of a fourth electrical signal port connection 50, and a fifth interrogator device 37 electrically connected to the fifth signal port 10 by means of a fifth electrical signal port connection 51 .

The first interrogator device 33 is arranged to transfer an interrogation signal to the first communication device 28 via the first signal port 6, the first RF feeder cable 16 and the first antenna port 1 1 . The first communication device 28 is arranged to transfer a reply signal, comprising certain data, to the first interrogator device 33. The creation and transmission of each reply signal is powered by energy comprised in each received interrogation signal.

All other interrogator devices 34, 35; 36, 37 are also arranged to communicate with corresponding communication device 29; 30, 31 , 32 in the same way. More in detail, the second interrogator device 34 is arranged to communicate with the fourth communication device 31 via the second RF feeder cable 17, the third interrogator device 35 is arranged to communicate with the fifth communication device 32 via the third RF feeder cable 18, the fourth interrogator device 36 is arranged to communicate with the second communication device 29 via the fourth RF feeder cable 19, and the fifth interrogator device 37 is arranged to communicate with the third communication device 30 via the fifth RF feeder cable 20.

For example, each communication device 28, 29; 30, 31 , 32 is constituted by a radio- frequency identification (RFID) device or tag. RFID tags are well-known in the art and are arranged to create and transmit a reply to an interrogation signal using the energy comprised in the received interrogation signal. An RFID tag does thus not need any power supply, since it uses the power comprised in each interrogation signal. An RFID tag is only active when polled by an interrogator device and the energy to respond is temporarily induced in the RFID tag.

The inventors have found an effective way to use RFID tags, letting interrogation signal and replies at least mainly being transferred via cables, in this case the same cables as those via which the RF signals are transferred. In this way, a secure, uncomplicated and inexpensive way for transceiver arrangements according to the above to acquire knowledge about the properties of the antenna ports that it is connected to. The data in a reply may for example comprise at least one of port identification and antenna type, and may be predetermined. All inquiries that lead to interrogations, and all replies, are stored and controlled by means of a control unit 57 comprised in the node; for reasons of clarity no connections to and from the control unit 57 are shown.

With reference to Figure 3, schematically showing a diagram of a second example of a wireless communication node V, the wireless communication node V comprises a first transceiver arrangement 2' and a second transceiver arrangement 3', where the first transceiver arrangement 2' comprises a first interrogator arrangement 23', and where the second transceiver arrangement 3' comprises a second interrogator arrangement 24'.

The transceiver arrangements 2', 3' correspond to the transceiver arrangements of the first example, except for the interrogator arrangement 23', 24'. The antenna systems 4, 5 correspond to the antenna systems of the first example. The first interrogator arrangement 23' comprises a first interrogator device 38 and a first switch arrangement 40, where the first switch arrangement 40 is arranged to connect the first interrogator device 38 to any one of the signal ports 6, 7, 8 in the first transceiver arrangement 2' via a corresponding first electrical signal port connection 47, second electrical signal port connection 48, and third electrical signal port connection 49. Correspondingly, the second interrogator arrangement 24' comprises a second interrogator device 39 and a first second arrangement 41 , where the second switch arrangement 41 is arranged to connect the second interrogator device 39 to any one of the signal ports 9, 10 in the second transceiver arrangement 3' via a corresponding fourth electrical signal port connection 50 and fifth electrical signal port connection 51 . In this way, for each transceiver arrangement 2', 3', only one interrogator device 38, 39 is needed, where the corresponding switch arrangement 40, 41 connects its interrogator device 38, 39 to the proper signal port 6, 7, 8, 9, 10 at the correct moment. This arrangement may minimize the number of interrogator devices 38, 39 needed. This means that, generally, each interrogator arrangement 23, 24; 23', 24' is at least electrically connectable to least one signal port 6, 7, 8; 9, 10,

In the following, different examples for the electrical antenna port connections 42, 43; 44 , 45, 46 and the electrical signal port connections 47, 48, 49; 50, 51 will be discussed with reference to Figure 4, schematically showing the first electrical antenna port connection 42, and Figure 5, schematically showing the first electrical signal port connection 47. Similar arrangements as shown for the first electrical antenna port connection 42 are used for all electrical antenna port connections 42, 43, 44, 45, 46, and similar arrangements as shown for the first electrical signal port connection 47 are used for all electrical signal port connection 47, 48, 49, 50, 51 .

As shown in Figure 4, the first electrical antenna port connection 42 comprises a first signal filter 55. Transmitted and received RF signals are carried at a first frequency band fi , and interrogation and reply signals are carried at a second frequency band f ₂ . This means that at the first antenna port 1 1 , signals at both frequency bands are present. At the first signal filter 55, the signals are separated such that signals at the first frequency band fi are transferred to and from the first antenna arrangement 25, and such that signals at the second frequency band h are transferred to and from the first communication device 28.

The signals at the second frequency band h are transferred between the first communication device 28 and the first signal filter 55 in many ways, for example via a direct connection or by means of electrical coupling in an electrical coupler such as for example a directional coupler, or via antennas.

In the latter case, as shown in Figure 4, the first communication device 28 is connected to a first antenna device 52, and the first signal filter is connected to a second antenna device 53. These antenna devices are arranged to transfer signals at the second frequency band h between the first communication device 28 and the first signal filter 55. In order to avoid signal leakage between different electrical antenna port connections 42, 43, 44, 45, 46, the signal strength may be suitably adapted, and/or the antennas devices 52, 53 may be positioned in an electrical enclosure 54 acting as a Faraday's cage.

As shown in Figure 5, the first electrical signal port connection 47 comprises a second signal filter 56. Transmitted and received RF signals are carried at the first frequency band fi , and interrogation and reply signals are carried at the second frequency band h- This means that at the first signal port 6, signals at both frequency bands are present. At the second signal filter 56, the signals are separated such that signals at the first frequency band fi are transferred to and from the first signal processing unit 21 , and such that signals at the second frequency band h are transferred to and from the first interrogation device 33. Here, the first interrogation device 33 is directly connected to the second signal filter 56, but other connections are of course conceivable, such as for example electrical coupling in an electrical coupler, such as for example a directional coupler. Depending on different types of equipment in the transceiver arrangements 2, 3 and the antenna systems 4, 5, and on how the different frequencies are allocated, the signal filters 55, 56 may not be necessary; either at one or more transceiver arrangements 2, 3 and/or at one or more antenna systems 4, 5. Therefore, in the example described above with the antenna devices 52, 53, each antenna port 1 1 , 12, 13, 14, 15 is at least indirectly connected to a corresponding second antenna device 53.

The present invention is not limited to the example described above, but may vary within the scope of the appended claims. For example, the number of transceiver arrangements, antenna systems may vary, but there is at least one transceiver arrangement 2, 3 and at least one antenna system 4, 5. The number of signal ports, and signal processing units in each transceiver arrangements may vary, and the number of antenna ports, antenna arrangements, and communication devices in each antenna system may vary. However, each transceiver arrangement 2, 3 comprises at least one signal port 6, 7, 8; 9, 10 and each antenna system 4, 5 comprises at least one antenna port 1 1 , 12; 13, 14, 15.

The number of interrogator devices in each interrogator arrangement may also vary, for example depending on the number of signal ports and if a switch device is used or not.

The RF feeder cables do not have to connect ports in the manner shown; the RF feeder cables should of course always be connected in the way required for the installation in question. The number of RF feeder cables and communication devices is dependent on the number of antenna ports that are to be connected to signal ports.

Generally, the present invention relates to a wireless communication node 1 comprising at least one transceiver arrangement 2, 3 and at least one antenna system 4, 5. Each transceiver arrangement 2, 3 comprises at least one signal port 6, 7, 8; 9, 10 and each antenna system 4, 5 comprises at least one antenna port 1 1 , 12; 13, 14, 15. Said transceiver arrangement 2, 3 is connected to said antenna system 4, 5 by means of at least one radio frequency, RF, feeder cable 16, 17, 18, 19, 20 running between corresponding signal ports 6, 7, 8; 9, 10 and antenna ports 1 1 , 12; 13, 14, 15 (or corresponding signal port/antenna port in the case of only one signal port/one antenna port). Each transceiver arrangement 4, 5 comprises a signal processing unit 21 , 22, and each antenna system 4, 5 comprises at least one antenna arrangement 25, 26; 27. Each antenna arrangement 25, 26; 27 is furthermore connected to at least one corresponding antenna port 1 1 , 12; 13, 14, 15, where each RF feeder cable 16, 17, 18, 19, 20 is arranged to transfer RF signals between a corresponding signal processing unit 21 , 22 and a corresponding antenna arrangement 25, 26; 27 via a corresponding signal port 6, 7, 8; 9, 10 and a corresponding antenna port 1 1 , 12; 13, 14, 15.

Each transceiver arrangement 2, 3 comprises an interrogator arrangement 23, 24, and each antenna system 4, 5 comprises at least one communication device 28, 29; 30, 31 , 32, where each communication device 28, 29; 30, 31 , 32 is electrically connected to a certain corresponding antenna port 1 1 , 12; 13, 14, 15 by means of a corresponding electrical antenna port connection 42, 43; 44, 45, 46. Said interrogator arrangement 23, 24 is at least electrically connectable to least one signal port 6, 7, 8; 9, 10, and is arranged to transfer an interrogation signal to a certain corresponding communication device 28, 29; 30, 31 , 32 via the corresponding signal port 6, 7, 8; 9, 10, the corresponding RF feeder cable 16, 17, 18, 19, 20 and the corresponding antenna port 1 1 , 12; 13, 14, 15. Each communication device 28, 29; 30, 31 , 32 is arranged to transfer a reply signal, comprising certain data, to said interrogator arrangement 23, 24 via the corresponding RF feeder cable 16, 17, 18, 19, 20. The creation and transmission of each reply signal is powered by energy comprised in each received interrogation signal.

The present invention also generally relates to an antenna system 4, 5 comprising at least one antenna port 1 1 , 12; 13, 14, 15 arranged to be connected to a transceiver arrangement 2, 3 by means of at least one corresponding radio frequency, RF, feeder cable 16, 17, 18, 19, 20. The antenna system 2, 3 comprises at least one communication device 28, 29; 30, 31 , 32, where each communication device 28, 29; 30, 31 , 32 is electrically connected to a certain corresponding antenna port 1 1 , 12; 13, 14, 15 by means of a corresponding electrical antenna port connection 42, 43; 44, 45, 46. Each communication device 28, 29; 30, 31 , 32 is arranged to transfer a reply signal via said antenna port 1 1 , 12; 13, 14, 15, the reply signal comprising certain data and being transferred in reply to an interrogation signal received via said antenna port 1 1 , 12; 13, 14, 15. The creation and transmission of each reply signal is powered by energy comprised in each received interrogation signal. Each antenna arrangement may comprise any suitable type of antenna, such as single column array antennas, multi-column array antennas and single element antennas such as for example reflector antennas. Each antenna arrangement may thus comprise one or more antenna elements; for example in the form of reflector antennas, patch antennas, slit antennas and/or dipole antennas. The antenna arrangements may comprise the same, similar or different types of antennas.

In the Figures, only those elements essential for describing the present matter in a clear manner are shown. Of course, a wireless communication node comprises several more components such as for example devices for power, communication and control, which are not shown here. All such components are considered as well- known in the art, and are neither shown, nor discussed, for reasons of clarity.

Above it is thus described how to use RFID Tags to label antenna port function/properties which lower costs and complexity for property reporting. The present invention offers a mechanism for cost effective identification and supervision of the antenna system using available RFID technology, enabling unique identification of what ports that are interconnected and the characteristics of each port.

The present invention can of course be combined with other types of signals, such as for instance AISG (Antenna Interface Standards Group) signals, over the RF feeder cables. Other communication devices having the described functionality are of course conceivable, the present invention not being limited to RFID devices or tags.

The wireless communication node 1 may be any suitable base station node in any wireless communication system and/or protocol, or a combination of such base station nodes.