Energy saving method for a network comprising ncr

Abstract

A method realized by a system comprising a base station (10) suitable for providing communication services to user equipment (40) and a network controlled repeater (NCR (20)) having a mobile termination means (21) and a forwarding means (22). In a first mode it comprises steps of. by base station (10) transmitting signaling information having instructions relating to common signaling to NCRs (20) through a control link (32); by mobile termination means (21) of NCR (20), realizing common signaling by sweeping its NCR (20) sweeping area by beamforming based on signaling information; by base station (10) realizing common signaling by sweeping its coverage area; and in a second mode base station's (10) amplification power of common signaling is increased and NCRs (20) are operated in energy saving mode.

Description

[0001] ENERGY SAVING METHOD FOR A NETWORK COMPRISING NCR

[0002] TECHNICAL FIELD

[0003] Invention relates to a method realized by a system comprising a base station suitable for providing communication services to user equipment and a network controlled repeater (NCR) having a mobile termination means and a forwarding means and a system thereof.

[0004] PRIOR ART

[0005] Network controlled repeater (NCR) is device introduced to the standards. A network-controlled repeater is a device used in telecommunications to regenerate or replicate signals that travel over long distances or through mediums that may cause signal degradation. Unlike traditional repeaters that simply amplify the signal they receive, network-controlled repeaters have the capability to be managed, monitored, and adjusted remotely through a network.

[0006] Energy saving is an important problem in wireless communication network standards. Saving energy is important in two aspects: network operation expenses and carbon dioxide emissions. Equipment for newer generations is more energy demanding but at the same time more flexible and capable. That explains the interest and focus by companies in standardization on energy saving; flexibility and dynamicity given by standards in system design give new opportunities for saving energy, which is more important than before for more energy-demanding hardware. In 3GPP (3rd Generation Partnership Project) standards, there were recent study items on energy saving for the two radio network sides, namely, user equipment (UE) and base station (BS).

[0007] New more-demanding applications came with the fifth generation urged standardization bodies to open new frequencies for communication systems. Millimeter-wave (mmWave) frequencies give much larger bands for system designers to accommodate such applications but also come with their own problems. The main problem is propagation loses. At higher frequencies, electromagnetic waves are less immune to propagation loses and for this reason, coverage is a major problem. To solve this issue, a direct solution would be increasing the number of base stations for the same served area. However, such approach has high capital and operating costs and not always feasible. Other solutions over the last few years were proposed, and one of the most prominent ones is the new concept of network-controlled repeaters (NCRs). Recently, a study item in 3GPP standards on NCR was concluded to processed farther with a work item on NCR to make it part of the standards.

[0008] Unlike classical amplify-and-forward (AF) relays, NCR is a smarter network unit in the sense that it can be controlled by the network. It has two functionalities: mobile termination and forwarding

[0018] . Mobile termination is a UE-like terminal that communicates with base station over the control link to receive instructions. The second forwarding functionality is identical to AF relay, where it receives signal from base station over the backhaul link, amplifies it, then direct it to UE over the access link. Control and backhaul links might be multiplexed in a time division duplex (TDD) manner. The former is decoded and processed in base band, while the latter is only amplified and forwarded to reduce the cost of NCR. NCR is smarter by means of control over its operation parameters, like beamforming, uplink (UL) and downlink (DL) amplification direction, ON and OFF states, and any other possible controls.

[0009] Base stations spend most of their time in low to no-load states. However, common signaling by those base stations is necessary for users joining or rejoining the network. As mentioned earlier, new generations enable more dynamic designs. Companies exploited that to propose different energy-saving solutions. Solutions are given in time, frequency, space, and power domains. The main idea is switching as much hardware as possible in the network side for power saving. When those solutions are applied to links enabled by NCR, however, NCR needs to be always active to amplify signals in both directions. Another problem with NCR- enabled links is the overhead; once a beam is established with NCR, all beams by NCR in addition to its own beams need to be swept by base station for common signals. This applies also to random access opportunities.

[0010] Energy saving is a problem that has been in standardization for long time. However, the new standards for 5G (5thgeneration) are more flexible and dynamic, so new solutions were recently proposed in standards for energy saving. In the following a review of those solutions is given. In addition, other solutions that are not directly related to energy saving and NCR are mentioned.

[0011] Standardization targets energy saving at two parts of the network, namely network side and user side

[0001] [2], At network side, energy saving solutions are categorized as follows: time, frequency, space, and power solutions [1]. Time-based solutions attempt to exploit new frame structure to enable longer sleep times for base stations. Frequency-domain solutions exploit other frequency resources to reduce common signaling overhead. Spatial-based solutions are proposed to switch on and off parts of base station hardware based on traffic load for energy saving. Finally, power-domain solutions focus on changing power levels of channels and signals for energy saving. In the following, main solutions in those domains are presented.

[0012] Solutions in time-domain focus on extending time of intervals of no activities for base station so it can sleep for longer periods. Base stations spend most of their time in idle mode with no active transmission to users. However, common signaling is necessary for users accessing the network.

[0013] The proposed solutions by companies in standards focus on base stations with zero to light loads. Solutions mainly fall under one of three approaches: manipulating periodicity, skipping some transmissions, or exploiting other resources for transmission.

[0014] One approach as analyzed in [3-7] is to send a light synchronization signal block (SSB). Lighting might omit parts of SSB or send a simplified version. Savings up to 30% were achieved. Another approach is to skip one or more common signals [8-9]. Numerical results were shown to save up to 25% approximately. Adjusting periodicity of common signals and random-access opportunities is also another approach to save energy in time domain [4- 5]

[0010]

[0011] . Savings were shown to reach 80%, however, there is effect on latency for users joining the network. Finally, Other approaches attempt to configure transmission patterns of common signals by for instance moving random-access opportunities to one place, where savings were shown to be up to 40%.

[0015] Similar to common signals, there are user-specific signals sent or received periodically. Examples include sounding reference signal in downlink or uplink, reporting, positioning signals, etc. By means of downlink control information (DCI), base station can activate and deactivate those user-specific signals. This technique aims to adapt their transmissions using DCI for improved energy efficiency.

[0016] In [4-5][9]

[0011] , a user equipment (UE) wake-up signal for base station was analyzed. This solution enables user instructing base station, so it moves from reduced or no transmission or reception state to active transmission or reception of a signal. For longer wake up signal periodicity, there is more saving but less uplink (UL) throughput due to the longer periodicity for random access opportunities. As shown in [8], the adaption of Discontinuous Reception / Discontinuous Transmission (DTX / DRX) also helps saving energy. New radio standards have two types of DRX: connected and idle DRXs. By aligning their periods in a user-based manner, base station achieves more time for deeper sleeps. The technique aims for a mechanism to inform UE of inactive periods at base station (BS) side. With such information, not only base station can align DRXs for better sleep periods, but also improvements at UE side is possible by omitting some cycles, user-aligned DRX pattern brings saving gains of 4%-7% depending on the traffic load and has slight impact on UE throughput / latency. Reducing base station activities (e.g. SSB) outside user DRX active time has remarkable energy saving effect with saving gain of at most 70%.

[0017] In frequency-domain, multi-carrier energy saving enhancement was achieved. Current specification supports intra-band SSB-less secondary cell (SCell) operation. The proposed technique enables inter-band SSB-less SCell operation. There is no SSB transmissions in some or all SCells. Synchronization and fast activation / deactivation are acquired from cells with SSB transmission or using light SSBs. For fast access on a SCell, mechanisms for user or base station to trigger SSB transmission might be used. Random access opportunity may be supported by SSB-less SCell. For SSB and / or SIB provided over one of two carriers, the results by companies show significant savings at lower loads (at lower loads the network might switch off the secondary cell for energy saving): no load, up to 98.4%; low load, up to 58.4%; light load, up to 7.9%; medium load, up to 5.7%.

[0018] In spatial domain, there are two main solutions. The first is adaption of spatial elements and the second is adaption of transmit-receive points (TRPs). The first technique relies on the adaption of used hardware at base station. This includes transceiver chains and number of active antenna panels used in transmission and reception, where savings can go up to 30% in the presented results by companies. The second technique aims to adapt the number of active TRPs used to serve a user configured to be served by multiple TRPs. For semi-static TRP configuration, energy saving gains can be up to 41.6% but with user perceived throughput losses up to 22%. For dynamic TRP reduction, savings are up to 28.7% with no impact on throughput.

[0019] As seen above, the focus in standards is base station; to the best of our knowledge, there are no discussions yet on solutions for links with NCR. However, the following are some patents on NCR related to energy saving.

[0020] In

[0013] , a solution is proposed to close and open repeater systems in a road network. The proposed solution focus on switching on and off the power amplifiers of repeaters, which is something already discussed in standards on NCR as shown in

[0014] , In

[0015] , power states for NCR were proposed, where the network can instruct NCR to switch on and off parts of components. Mainly, those components are the control and traffic hardware separate. Different power saving solutions at NCR itself are presented in

[0016] . A method for controlling power levels in communication links of NCR is proposed in

[0017] ,

[0021]

[0001] 3GPP TR 38.864 Study on network energy savings for NR.

[0022] [2] 3GPP TR 38.840 Study on User Equipment power saving in NR.

[0023] [3] 3GPP R1 -2210858 Evaluation results and other performance aspects for network energy savings.

[0024] [4] 3GPP R1 -221 1018 Discussions on NW energy savings performance evaluation.

[0025] [5] 3GPP R1 -2212541 Discussions on NW energy savings performance evaluation.

[0026] [6] 3GPP R1 -2212429 Discussion on Network energy saving techniques.

[0027] [7] 3GPP R1 -2213000 NW energy savings performance evaluation.

[0028] [8] 3GPP R1 -221 1458 Discussion on NW energy savings performance evaluation.

[0029] [9] 3GPP R1 -2212543: "NW energy savings performance evaluation.

[0030]

[0010] 3GPP R1 -2211692 Discussion on network energy saving techniques.

[0031]

[0011] 3GPP R1 -2211097 NW energy savings performance evaluation.

[0032]

[0012] 3GPP R1 -2211903 Evaluation results of NW energy saving techniques.

[0033]

[0013] CN115802462A Energy-saving method and system for repeater system on road network

[0034]

[0014] 3GPP TR38.867 Study on NR network-controlled repeater.

[0035]

[0015] WO2023199229A1 Power saving modes of operation for network-controlled repeaters.

[0036]

[0016] US2023054824A1 Ppower saving for wireless repeaters.

[0037]

[0017] CN1 14189269A Uplink and downlink power control method and device for intelligent repeater

[0038]

[0018] A Comparison between Network-Controlled Repeaters and Reconfigurable Intelligent Surfaces

[0039] BRIEF DESCRIPTION OF THE INVENTION

[0040] The present invention relates to a method to eliminate the above-mentioned disadvantages and bring new advantages to the relevant technical field.

[0041] An object of the invention is to reduce power consumption of a system comprising base station and network controllers. To achieve all the objects mentioned above and that will emerge from the following detailed description, the present invention relates to a method realized by a system comprising a base station suitable for providing communication services to user equipment and a network controlled repeater (NCR) having a mobile termination means and a forwarding means. Accordingly, it comprises the steps of:

[0042] - by base station transmitting signaling information having instructions relating to common signaling to NCRs through a control link;

[0043] - by mobile termination means of NCR, realizing common signaling by sweeping its NCR sweeping area by beamforming based on signaling information;

[0044] - by base station realizing common signaling by sweeping its coverage area; or the steps of:

[0045] - by base station transmitting idle information through a control link having instructions for NCRs to operate in a power saving mode;

[0046] - by NCRs operating in the power saving mode based on idle information;

[0047] - by base station increasing amplification power of its common signaling such that it covers NCR sweeping areas;

[0048] - by base station realizing common signaling by sweeping its boosted coverage area. In conventional systems each additional NCR adds more beams. As base station is sweeping, it needs to stop at the beam connecting one NCR and send the same common signal repeatedly so that NCR spans its region and direct the common signals it receives and amplifies. Instead of generating the common signal at base station and consume power to send it to NCR, and then NCR consumes power to amplify it and forward it, NCR generates the signal by itself and send it using the same power it would consume at amplifying. In this manner, base station power is saved. Thus, NCR and base station transmits common signals independently, covering a coverage area in more efficient way, reducing power consumption of base station or reducing power consumption of NCRs by boosting coverage area of base station selectively.

[0049] In a possible embodiment, in first mode NCRs are synchronized to base station in order to allow random access; and method comprises the step of: operating forwarding means for random access process.

[0050] In a possible embodiment, second mode comprises the step of:

[0051] - by base station transmitting information to user equipment to reduce impact of signal power level while cell selection. This causes reducing the effect of increased signal power on unnecessary handovers. In a possible embodiment, in second mode NCRs are synchronized to base station in order to allow random access; by base station turning on NCRs based on random access requests.

[0052] The invention is also a system which is configured to realize above method.

[0053] BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 is a drawing illustrating top schematic view of the system.

[0055] Figure 2 is a drawing illustrating independent common signaling of base station and NCR.

[0056] Figure 3 is drawing illustrating where, base station realizes common signaling in a boosted manner.

[0057] REFERENCE NUMBERS GIVEN IN THE FIGURE

[0058] 10 Base station

[0059] 20 NCR

[0060] 21 Mobile termination means

[0061] 22 Forwarding means

[0062] 31 Backhaul link

[0063] 32 Control link

[0064] 33 Access link

[0065] 40 User equipment

[0066] DETAILED DESCRIPTION OF THE INVENTION

[0067] In this detailed description, the subject matter is explained with references to examples without forming any restrictive effect only in order to make the subject more understandable.

[0068] Current systems (networks) comprising at least a base station (10) and a network-controlled repeater (NCR (20)). Base station (10) realizes common signaling by amplifying, beamforming common signals and sweeping its coverage area. NCRs (20) use its forwarding function and receives common signals, amplify them and sweeps its coverage area using beamforming. In this structure, base station’s (10) sweeps cover NCR (20) as well. The invention provides a method and system which realizes common signaling using reduced power.

[0069] Referring to figure 1 , system comprises a base station (10) and NCRs (20). Base station (10) is capable of realizing common signaling as well as other functionalities well known in the art. Base station (10), as well known in the art, equipped with transmission and reception equipment and software. Base station (10) is capable of adjusting its amplification power of transmitted signals, thus increasing or decreasing its coverage area. NCR (20) comprises a forwarding means (22) for realizing forwarding. Forwarding means (22) is capable of receiving signals, amplifying them and forwarding them. Forwarding means (22) comprises hardware and software components in order to realize forwarding. Details of such components are not disclosed herein since it is general practice and well known in the art. User equipment (40) receive communication services from base station (10) and NCR (20). User equipment (40) is connect to NCR (20) via an access link (33).

[0070] NCRs (20) are capable of mobile termination and forwarding. NCR (20) comprises a mobile termination means (21 ) for realizing mobile termination. Mobile termination means (21 ) comprises hardware and software components of NCR (20) that realizes mobile termination. Further details of mobile termination are not disclosed herein as it is well known in the prior art.

[0071] NCR (20) is connected to base station (10) over a control link (32). NCR (20) receives instructions from base station (10) over control link (32).

[0072] NCR (20) is connected to base station (10) over backhaul link (31 ) as well. NCR (20) may receive data to be forwarded over backhaul link (31 ). Control link (32) and backhaul link (31 ) may be multiplexed.

[0073] The system realizes below steps in order reduce overall power consumption in the system during common signaling:

[0074] - by base station (10) transmitting signaling information having instructions relating to common signaling to NCRs (20) through a control link (32);

[0075] - by mobile termination means (21 ) of NCR (20), realizing common signaling by sweeping its NCR (20) sweeping area by beamforming based on signaling information;

[0076] - by base station (10) realizing common signaling by sweeping its coverage area excluding said NCR (20) sweeping areas; or the steps of:

[0077] - by base station (10) transmitting idle information through a control link (32) having instructions for NCRs (20) to operate in a power saving mode;

[0078] - by NCRs (20) operating in the power saving mode based on idle information;

[0079] - by base station (10) increasing amplification power of its common signaling such that it covers NCR (20) sweeping areas;

[0080] - by base station (10) realizing common signaling by sweeping its boosted coverage area.

[0081] According to above method, the system selectively operates in two modes. Referring to fig. 2 in a first mode base station (10) and NCR (20) realizes common signaling independently from each other. Thus reduces power consumption of base station (10). Signaling information may comprise cell id and other known information relating to common signaling. In this mode, NCR (20) forwarding functionality may be used for random access opportunities at base station (10). Since NCR (20) generates common signals locally, base station (10) synchronization with NCR (20) so that in random access opportunities base station (10) can compensate for time and frequency offsets. NCRs (20) are fully instructed by base station (10) to align their signaling and listening periods.

[0082] Instead of generating the common signal at base station (10) and consume power to send it to NCR (20), and then NCR (20) consumes power to amplify it and forward it, NCR (20) generates the signal by itself and send it using the same power it would consume at amplifying. In this manner, base station’s (10) power is saved.

[0083] NCR (20) realizes common signalling independent of base station (10), base station (10) transmits instructions when and how often to realize it. The base station (10) might instruct multiple connected NCRs (20) to manage their signalling for different purposes like interference management. Random access opportunities are more restricted. In this case, users try to send signal to base station (10) and NCR (20) must be on and amplify in the uplink direction. However, NCRs (20) might be switched on only when base station (10) is listening in their area. Sweeping during random access opportunities also has more overhead.

[0084] Referring to figure 3, in a second mode base station (10) increases amplification power of transmitted common signal so it extends to NCR (20) coverage area. In this mode, power saving mode may be a turned off mode, or idle mode. Thus, energy saving may be realized on NCR (20) side. In systems having increased NCRs (20) power saving may be realized. Common signals are sent by base station (10) at higher power level with no NCR (20) assistance. The boosted power might cause users to select the base station (10) while another is better. To solve this issue, base station (10) might adjust power levels to get close in receive power through the link assisted by NCR (20). NCRs (20) in this case might need to be grouped in different beams. Information explicitly indicating not to rely on measured power levels might be delivered to users as another solution. Users might use other information signals at later stages for such measures. Base station (10) needs to synchronize with NCR (20), so that users have initial synchronization in random access opportunities. In random access, only relevant NCRs (20) might be turned on.

[0085] Common signal described in this description may be any other signal that is common to NCR (20) and base station (10) for realizing a common task for different purposes.

[0086] The scope of protection of the invention is specified in the attached claims and cannot be limited to those explained for sampling purposes in this detailed description. It is evident that a person skilled in the art may exhibit similar embodiments in light of the above-mentioned facts without drifting apart from the main theme of the invention

Claims

CLAIMS1. A method realized by a system comprising a base station (10) suitable for providing communication services to user equipment (40) and a network controlled repeater (NCR(20)) having a mobile termination means (21 ) and a forwarding means (22) characterized in that in a first mode comprising the steps of:- by base station (10) transmitting signaling information having instructions relating to common signaling to NCRs (20) through a control link (32); by mobile termination means (21 ) of NCR (20), realizing common signaling by sweeping its NCR (20) sweeping area by beamforming based on signaling information;- by base station (10) realizing common signaling by sweeping its coverage area; or in a second mode comprising the steps of:- by base station (10) transmitting idle information through a control link (32) having instructions for NCRs (20) to operate in a power saving mode;- by NCRs (20) operating in the power saving mode based on idle information;- by base station (10) increasing amplification power of its common signaling such that it covers NCR (20) sweeping areas;- by base station (10) realizing common signaling by sweeping its boosted coverage area.

2. The method according to claim 1 wherein in first mode NCRs (20) are synchronized to base station (10) in order to allow random access; and method comprises the step of: operating forwarding means (22) for random access process.

3. The method according to one of the claims 1 or 2 characterized in that second mode comprising the step of:- by base station (10) transmitting information to user equipment (40) to reduce impact of signal power level while cell selection.

4. The method according to claim 1 characterized in that in second mode NCRs (20) are synchronized to base station (10) in order to allow random access; by base station (10) turning on NCRs (20) based on random access requests.

5. The method according to claim 1 wherein in power saving mode NCRs are turned off.

6. A system comprising a base station (10) suitable for providing communication services to user equipment (40) and a network controlled repeater (NCR(20)) having a mobile termination means (21 ) and a forwarding means (22) wherein the system is configured to realize the method of claim 1 .

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