CROSS REFERENCE TO RELATED APPLICATIONS

This application is a 35 U.S.C. § 371 National Stage of International Patent Application No. PCT/EP2018/086390, filed Dec. 20, 2018.

TECHNICAL FIELD

The present disclosure relates to an antenna system comprising a first set of antenna ports, a second set of antenna ports separate from the first set of antenna ports, and a third set of antenna ports that at least partly comprises each one of the first set of antenna ports and the second set of antenna ports. The antenna system further comprises a transmitter arrangement and a receiver.

BACKGROUND

Active Antenna Systems (AAS) is an important part of LTE (Long Term Evolution) and an essential part of 5G. AAS is a generic term that is often used to describe base stations that incorporate a large number of separate transmitters and antenna elements that can be used for MIMO (Multiple Input Multiple Output) and beamforming as an integrated product. This will be one of the key aspects of 5G as the industry moves higher up in frequency and more complex array antenna geometries are needed to achieve the desired link budget.

Often the IBW (instantaneous bandwidth) of AAS products is lower than the actual need/wish du to hardware limitations. This can be a limitation if the operator has access to a larger frequency band or scattered sub-bands.

One solution is to split the product into two parts. This would enable two separate IBW:S and make it possible to use frequencies in different parts of a wide band. However, half the antenna size and half the number of transmit/receive-branches will decrease the up-link (UL) budget by 3 dB, and the down-link (DL) budget by 3 dB (6 dB relative to max for one beam).

Existing AAS systems are often UL-limited due to limited UE output power, hence a degraded UL budget of 3 dB can be a severe problem.

There is thus a need to provide an antenna system without the above limitations, in particular without degrading UL performance.

SUMMARY

It is an object of the present disclosure is to provide an antenna system that is efficiently handles the available communication resources for taking advantage of the available bandwidth or bandwidths. It is also an object of the present disclosure to provide a corresponding method and wireless communication node

Said object is obtained by means of an antenna system comprising a first set of antenna ports, a second set of antenna ports separate from the first set of antenna ports, and a third set of antenna ports that at least partly comprises each one of the first set of antenna ports and the second set of antenna ports. The antenna system further comprises a transmitter arrangement and a receiver. The transmitter arrangement comprises a first transmitter adapted for transmission of signals by means of a first downlink communication resource via the first set of antenna ports and a second transmitter adapted for transmission of signals by means of a second downlink communication resource via the second set of antenna ports. The receiver is adapted for reception of signals by means of a first uplink communication resource and a second uplink communication resource via the third set of antenna ports. Each communication resource defines, or is associated with, a certain bandwidth.

In this way, larger or scattered communication resources can be supported, enabling a lower product cost.

According to some aspects, at least one communication resource at least comprises one of a frequency channel, a time slot. and a coded channel.

This means that many types of communication resources are supported by means of the present disclosure.

According to some aspects, the first transmitter is adapted for transmission of signals within a first frequency band and the second transmitter is adapted for transmission of signals within a second frequency band that at least partly is spectrally separated from the first frequency band. The receiver is adapted for reception of signals within a third frequency band that comprises at least the first frequency band and the second frequency band.

According to some aspects, the antenna system comprises a switch assembly that is adapted to switch the sets of antenna ports to either the transmitter arrangement or to the receiver arrangement.

This enables TDD (Time Division Duplex).

According to some aspects, the first transmitter is adapted for transmission of signals within a first frequency band and the second transmitter is adapted for transmission of signals within a second frequency band. The receiver is adapted for reception of signals within a third frequency band and a fourth frequency band, where all the frequency bands are mutually spectrally separated.

According to some aspects, the antenna system comprises a filter assembly that is adapted to filter signals between on one hand the antenna ports and on the other hand the transmitter arrangement and the receiver arrangement.

This enables FDD (Frequency Division Duplex).

According to some aspects, each frequency band corresponds to a corresponding instantaneous bandwidth.

According to some aspects, the antenna system is an active antenna system (AAS).

This means that the present disclosure can be applied to AAS:s.

According to some aspects, the antenna system comprises an antenna arrangement which in turn comprises at least one antenna device of a first polarization.

According to some aspects, the antenna system comprises an antenna arrangement which in turn comprises at least one antenna device of a second polarization that is orthogonal to the first polarization.

This means that the present disclosure can be applied to antenna systems where an antenna arrangement either is single polarized or dual polarized.

According to some aspects, each set of antenna ports comprises at least one antenna port connected to at least one antenna device of the first polarization and at least one antenna port connected to at least one antenna device of the second polarization. Different antenna ports are here connected to different antenna devices.

According to some aspects, the first set of antenna ports comprises antenna ports connected to at least one antenna device of a first polarization, and where the second set of antenna ports comprises antenna ports connected to at least one antenna device of a second polarization that is orthogonal to the first polarization. Different antenna ports are here connected to different antenna devices.

According to some aspects, the antenna system comprises an antenna arrangement which in turn comprises a first number of rows of antenna devices and a second number of columns of antenna devices.

According to some aspects, the first set of antenna ports is connected to a first set of columns comprising a comprising a third number of columns and the second set of antenna ports is connected to a second set of columns, separate from the first set of columns and comprising a fourth number of columns. The third set of antenna ports comprises each one of the first set of antenna port and the second set of antenna ports.

In this way, two antenna sub-arrays are formed and placed side by side.

According to some aspects, the first set of antenna ports is connected to a first set of rows comprising a fifth number of rows, and the second set of antenna ports is connected to a second set of rows, separate from the first set of rows and comprising a sixth number of rows. The third set of antenna ports comprises each one of the first set of antenna ports and the second set of antenna ports.

In this way, two antenna sub-arrays are formed, where one antenna sub-array is placed on top of the other antenna sub-array.

The present disclosure also relates to a wireless communication node and a method, which are associated with the advantages mentioned above.

