Decode-and-forward relay assisted transmission method for cell edge users
Patent Information
- Application Number
- PCT/TR2025/050204
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-03-05
- Publication Date
- 2025-10-02
AI Technical Summary
Users at the cell edge in RSMA systems using DF relays face challenges with signal-to-noise ratio (SNR) issues due to decoding and forwarding delays, and the complexity of Successive Interference Cancellation (SIC) is exacerbated in high user density scenarios, leading to potential errors and low SNR despite enhanced signal strength.
A data transmission method that divides messages into private and common parts, employs RSMA for encoding and relaying, and utilizes diversity and SIC techniques at both the base station and user equipment to enhance SNR, leveraging the common signal for diversity and combining it with the private signal to improve overall reception quality.
The method significantly increases the signal-to-noise ratio for cell edge users by leveraging the common signal for diversity, effectively addressing SNR issues and enhancing the reliability and coverage of RSMA systems, particularly at the cell edge.
Smart Images
Figure TR2025050204_02102025_PF_FP_ABST
Abstract
Description
[0001] DECODE-AND-FORWARD RELAY ASSISTED TRANSMISSION METHOD FOR CELL EDGE USERS
[0002] TECHNICAL FIELD
[0003] Invention is a data transmission method realized by a system comprising a base station providing a cell, plurality of user equipment connected to said cell and at least a decode and forward (DF) relay for relaying communication signals transmitted from base station to user equipment. In particular it relates to a Rate-Splitting Multiple Access (RSMA) method.
[0004] PRIOR ART
[0005] Rate-Splitting Multiple Access (RSMA) is a progressive technique in wireless communications that aims to overcome the limitations inherent in traditional Multiple Access methods. It functions by partitioning user messages into two segments: a common part and a private part. The common part is intended to be decoded by all users in the network, whereas the private part is targeted towards specific users. This division of data allows for more effective management of interference and increases spectral efficiency, making RSMA an attractive solution in environments characterized by high user density and varying quality-of-service demands.
[0006] One of the key applications of RSMA is in systems that employ Decode and Forward (DF) relays. In these systems, the relay nodes decode the received signal and then forward the reencoded signal to the intended recipients. This methodology enhances signal coverage and reliability, particularly beneficial for users situated at the cell edge, who often experience weak signal strength due to their distance from the base station.
[0007] However, there are several challenges associated with RSMA applications that utilize DF relays. Users at the cell edge, despite the benefits of enhanced signal strength, may still face issues due to the inherent delays and potential errors in the decoding and forwarding process at the relay nodes.
[0008] Another critical challenge is associated with Successive Interference Cancellation (SIC) in RSMA systems. SIC is a technique used to mitigate interference by successively decoding and canceling out the interfering signals. However, in RSMA systems, especially those using DF relays, the implementation of SIC becomes more complex. The relay nodes need to perform SIC effectively to ensure the integrity of both the common and private parts of the message. This complexity is further compounded in scenarios with high user density, where the interference patterns can be more intricate. Further, users at cell edge may still experience low signal to noise ratio (SNR) despite using DF.
[0009] Overall, while RSMA offers significant advantages in terms of interference management and spectral efficiency, its implementation in systems using DF relays presents unique challenges, particularly for users at the cell edge and in the context of SIC. Addressing these challenges is crucial for the effective deployment of RSMA in advanced wireless communication systems.
[0010] All the problems mentioned above have made it necessary to make an innovation in the relevant technical field as a result.
[0011] BRIEF DESCRIPTION OF THE INVENTION
[0012] The present invention relates to a method and a system to eliminate the above-mentioned disadvantages and bring new advantages to the relevant technical field.
[0013] An object of the invention is to increase signal to noise ratio of received message of cell edge user equipment particularly in RSMA scheme.
[0014] Another object of the invention is to increase signal to noise ratio of received message of cell edge user equipment in RSMA scheme.
[0015] To achieve all the objects mentioned above and that will emerge from the following detailed description, the present invention relates to a data transmission method realized by a system comprising a base station providing a cell, plurality of user equipment connected to said cell and at least a decode and forward (DF) relay for relaying communication signals transmitted from base station to user equipment (UE) located at cell edge characterized in that comprising following steps:
[0016] - by base station acquiring at least a message W to be sent to at least one cell edge UE;
[0017] - by base station , dividing message W into private part p and common part c;
[0018] - generating a private message P for cell edge UEs and generating a common message C using generated common parts c and generated private parts p; - by base station encoding and transmitting said private message P
[0001] and said common message C
[0001] ;
[0019] - by DF relay, receiving the private message P
[0001] and the common message C
[0001] ;
[0020] - by DF relay, transmitting private message P[2] and common message C[2] to cell edge UE ;
[0021] - by cell edge UE (102) receiving common message C[1], common message C[2], private message P[2];
[0022] - decoding common message C
[0001] and obtaining and storing private part p’[1] and / or common part c’
[0001] ;
[0023] - by cell edge UE applying diversity to a private part p’[2] and / or a common part c’[2] obtained from common message C[2] and private message P[2] using a private part p’
[0001] or to a common part c’
[0001] decoded from stored common message C
[0001] ;
[0024] - generate message W’ using diversified common part c’[2] and private part p’[2] or using diversified common part c’[2] and diversified private part p’[2] or using common part c’[2] and diversified private part p’[2]. Thus, an otherwise ignored signal in prior art is utilized in order to improve signal to noise ratio of received signal in edge users.
[0025] A possible embodiment of the invention is characterized in that the step “generating a private message P for cell edge UEs and generating a common message C using generated common parts c and generated private parts p” comprises sub-steps of:
[0026] - by base station combining common parts c and obtaining a common message C using a Rate-Splitting Multiple Access (RSMA) scheme;
[0027] - by base station combining said private parts p and obtaining a private message P using the RSMA scheme; method further comprising steps of:
[0028] - by cell edge UE acquiring and storing a common part c’[1] by decoding common message C[1];
[0029] - by cell edge UE acquiring a common part c’[2] by decoding common message C[2] and private message P[2];
[0030] - by cell edge UE applying diversity to common part c’[2] using stored common part c’
[0001] and obtaining a common part c’;
[0031] - by cell edge UE applying successive interface cancellation (SIC) and decoding to common message C[2] and private message P[2] and common part c’ and obtaining private part p’;
[0032] - by cell edge UE combining common part c’ and private part p’ and generating message W’. Another possible embodiment of the invention is characterized in that the step “generating a private message P for cell edge UEs and generating a common message C using generated common parts c and generated private parts p” comprises sub-steps of:
[0033] - by base station combining private parts p and obtaining a common message C using a Rate- Splitting Multiple Access (RSMA) scheme;
[0034] - by base station combining said common parts c and obtaining a private message P using the RSMA scheme; method further comprising steps of:
[0035] - by cell edge UE acquiring and storing a private part p’
[0001] by decoding common message C
[0001] ;
[0036] - by cell edge UE acquiring a common part c’ by decoding common message C[2] and private message P[2];
[0037] - by UE cell edge acquiring private part p’[2] by applying successive interface cancellation (SIC) and decoding to common message C[2] and private message P[2] and common part c’;
[0038] - by cell edge UE applying diversity to private part p’[2] using stored private part p’[1] and obtaining a common part p’;
[0039] - by cell edge UE applying successive interface cancellation (SIC) to common message C[2] and private message P[2] and common part c’ and obtaining private part p’;
[0040] - by cell edge UE combining common part c’ and private part p’ and generating message W’.
[0041] Another possible embodiment of the invention is characterized in that the step “generating a private message P for cell edge UE and generating a common message C using generated common parts c and generated private parts p” comprises sub-steps of:
[0042] - by base station combining common parts c, private parts p and obtaining a common message C using a Rate-Splitting Multiple Access (RSMA) scheme;
[0043] - by base station combining private parts p and obtaining a private message P using the RSMA scheme; method further comprising steps of:
[0044] - by cell edge UE acquiring and storing a common part c’[1] and private part p’[1] by decoding and splitting common message C
[0001] ;
[0045] - by cell edge UE acquiring a common part c’[2] by decoding common message C[2] and private message P[2];
[0046] - by cell edge UE applying diversity to common part c’[2] using stored common part c’
[0001] and obtaining a common part c’;
[0047] - by cell edge UE applying successive interface cancellation (SIC) and decoding to common message C[2] and private message P[2] and common part c’ and obtaining private part p’[2] ; - by cell edge UE applying diversity to private part p’[2] using stored private part p’[1] and obtaining a private part p’;
[0048] - by cell edge UE combining the common part c’ and the private part p’ and generating message W’.
[0049] Another possible embodiment of the invention is characterized that the step “by DF relay, receiving the private message P[1] and the common message C[1]“ comprises sub steps of:
[0050] - acquiring common part c’
[0001] and private part p’
[0001] by decoding and splitting common message C
[0001] and private message P
[0001] ;
[0051] - applying successive interface cancellation (SIC) and decoding to common message C
[0001] and private message P[1] and common part c’
[0001] and obtaining private part p’
[0001] ;
[0052] - applying diversity to common part c’[1] and private part p’
[0001] and generating a private message P [2] and common message C[2] using private part p’
[0001] and common part c’
[0001] . Thus, signal to noise ratio is further increased at DF relay.
[0053] Invention is also a system comprising a base station providing a cell, plurality of user equipment connected to said cell and at least a decode and forward (DF) relay for relaying communication signals transmitted from base station (200) to user equipment (UE) located at cell edge capable of realizing one of the method such as explained above, base station comprising a BS message splitter configured to split a message W, to be sent to a cell edge UE into private part p and common part c; a BS private combiner configured to generate a private message P for cell edge UEs and a BS common combine configured to generate a common message C using generated common parts c and private parts p; a BS encoder for encoding private message P[1] and said common message C[1]; a BS transmitting means configured to transmit the private message P
[0001] and the common message C
[0001] ; the DF relay comprises a relay receiving means configured to receive the private message P
[0001] and the common message C[1] and relay transmitting means for transmitting private message P[2] and common message C[2] to cell edge UE; the cell edge UE comprises receiver means configured to receive common message C[1], common message C[2], private message P[2]; cell edge UE comprises an UE decoder configured to decode common message C
[0001] and obtaining and private part p’[1] and / or common part c’[1]; an UE buffer for storing common message C
[0001] and obtaining and private part p’[1] and / or common part c’
[0001] ; comprising a UE first decoder and a UE second decoder configured to decode common message C[2] and private message P[2] to obtain a private part p’[2] and / or a common part c’[2] ; a UE diversity unit configured to apply diversity to a private part p’[2] and / or a common part c’[2] using common part c’[1] and or private part p’
[0001] ; an UE combiner configured to generate message W’ using diversified common part c’[2] and private part p’[2] or using diversified common part c’[2] and diversified private part p’[2] or using common part c’[2] and diversified private part P’[2].
[0054] Another possible embodiment of the invention is characterized that DF relay comprises a relay first decoder and a second relay decoder configured to decode message C
[0001] and private message P
[0001] for obtaining common part c’[1] and private part p’
[0001] ; a relay SIC unit configured to apply successive interface cancellation (SIC) to common message C
[0001] and private message P[1] and common part c’[1]; an diversity means (not shown) configured to apply diversity to common part c’[1] and private part p’
[0001] ; a relay encoder configured to generate a private message P[2] and common message C[2] using private part p’[1] and common part c’
[0001] ,
[0055] BRIEF DESCRIPTION OF THE DRAWINGS
[0056] Figure 1 is a drawing illustrating top schematic view of the system.
[0057] Figure 2 is a drawing illustrating detailed view of base station.
[0058] Figure 3a is a drawing illustrating detailed view of receiver part of user equipment.
[0059] Figure 3b is a drawing illustrating detailed view of receiver part of user equipment.
[0060] Figure 4 is a drawing illustrating detailed view of DF relay.
[0061] Figure 5 is a drawing illustrating flow chart of a first embodiment of the method.
[0062] Figure 6 is a drawing illustrating flow chart of a second embodiment of the method.
[0063] Figure 7 is a drawing illustrating flow chart of a third embodiment of the method.
[0064] REFERENCE NUMBERS GIVEN IN THE FIGURE
[0065] 10 System 100 User equipment
[0066] 110 UE decoder
[0067] 121 UE first decoder
[0068] 122 UE second decoder
[0069] 130 UE diversity unit
[0070] 140 UE Splitter
[0071] 150 UE SIC unit
[0072] 160 UE buffer
[0073] 170 UE Combiner
[0074] 180 receiver means
[0075] 101 Center UE
[0076] 102 Cell edge UE
[0077] 1021 A first cell edge UE
[0078] 1022 A second cell edge UE
[0079] 200 Base station
[0080] 210 Scheduler
[0081] 220 BS Message splitter
[0082] 231 BS Common combiner
[0083] 232 BS Private combiner
[0084] 240 BS Encoder
[0085] 250 BS Linear precoder
[0086] 260 BS Transmitting means
[0087] 300 DF relay
[0088] 310 Relay receiving means
[0089] 321 Relay first decoder
[0090] 322 Relay second decoder
[0091] 330 Relay SIC unit
[0092] 340 Relay message splitter
[0093] 350 Relay encoder
[0094] 360 Relay linear precoder
[0095] 370 Relay transmitting means
[0096] 400 Cell
[0097] 410 Cell edge
[0098] 420 Cell center
[0099] DETAILED DESCRIPTION OF THE INVENTION 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.
[0100] Invention is a data transmission method realized by a system (10) comprising a base station (200) providing a cell (400), plurality of user equipment (100) connected to said cell (400) and at least a decode and forward relay (DF relay (300)) for relaying communication signals transmitted from base station (200) to user equipment (100). Invention is also said system (10).
[0101] Referring to figure 1 , the system (10) comprises at least a base station (200) providing communication services through a cell (400) to user equipment (100). At least a DF relay (300) is provided for relaying signals transmitted from base station (200) to user equipment (100). In a possible embodiment system (10) uses Rate-splitting multiple access (RSMA) scheme for transmitting signal.
[0102] Base station (200) may be any transmitter node capable of RSMA transmission. DF relays (300) may be any node with DF capabilities. User equipment (100) may also be any user equipment (100), another BS, unmanned aerial vehicles and any node with receiving capabilities.
[0103] User equipment (100) located near cell edges (410) are defined as cell edge (410) user equipment (100). User equipment (100) located near a cell center (420) is defined as a center UE (101 ).
[0104] Message transmission in the subject matter method may be defined in two parts. In a first transmission phase, base station (200) transmits a common signal omnidirectionally to user equipment (100) and to DF relays (300); and transmits private signals to DF relays (300). In a second transmission phase, DF relay (300) transmits / relays received common signals and private signals to cell edge (410) user equipment (100). User equipment (100) then utilizes common signal from first phase in order to increase signal to noise ratio (SNR) of common signal and / or private signal received in second phase.
[0105] Referring to figure 2, base station (200) comprises a scheduler (210) which is configured to select user equipment (100) requesting transmission and forwards a message W to a BS message splitter (220). Data to be send may for instance be (but not limited to) represented as (message W1 , message W2, and message W3). Here, message W1 represents the data of the center UE (101 ) which is a user equipment (100) located near cell center (420). Message W2 and message W3 represents the data of a first cell edge UE (1021 ) and a second cell edge UE (1022) which are user equipment (100) located near cell edges (410).
[0106] The message splitter is configured to divide user messages into common parts c and private parts p. For each user equipment (100) it would be represented as common part c1 , c2, c3, and private part p1 , p2, p3 for each user equipment (100). A BS common combiner (231 ) combines the common parts c (c1 , c2, c3) for each user equipment (100) using conventional RSMA to obtain a common message C. A BS private combiner (232), combines the private parts p (p2, p3) of cell edge (410) user equipment (100) as private message P. Subsequently, the combined common message C, the combined private message P of cell edge (410) user equipment (100) are encoded a BS encoder (240). In a second embodiment base station (200) may combine private parts p and obtaining a common message C using a Rate-Splitting Multiple Access (RSMA) scheme and combine common parts c and obtaining a private message P using the RSMA scheme. In a third embodiment base station (200) may combine common parts c, private parts p and obtaining a common message C using a Rate-Splitting Multiple Access (RSMA) scheme; combine private parts p and obtaining a private message P using the RSMA scheme.
[0107] Any coding scheme, such as Polar coding, LDPC (Low-Density Parity-Check) coding, Turbo coding, etc., can be employed at the base station (200) or user equipment (100). Encoded messages are then precoded with a BS linear precoder (250). Subsequently, precoded messaged are transmitted by a BS transmitting means (260) through a channel as part of the RSMA transmission to the cell edge (410) user equipment (100).
[0108] As mentioned above message transmission may be defined in two parts. In the first transmission phase, base station (200) transmits precoded messages. In the first transmission messages are transmitted to user equipment (100) and DF relay (300). In second transmission phase, DF relay (300) relays received messages.
[0109] During the first transmission phase, the common signal is transmitted omnidirectionally, while the private signal of the cell center (420) user may be conveyed using space division multiple access (SDMA), following the conventional RSMA transmission. Similarly, the private signals of the cell edge (410) users may be collectively sent to the relay node using SDMA. Base station (200) transmits signal which comprises a private message P[1] and a common message C
[0001] as defined above.
[0110] Center UE (101 ) receives conventional RSMA to retrieve related private part p1 and common part p2 from received signal.
[0111] Referring to figure 3a, cell edge UE (102) comprises a UE receiver means (180) for receiving common signal C
[0001] from base station (200) despite having a low signal-to-noise ratio (SNR). Thanks to the RSMA feature, the common signal is broadcasted to all destinations (user equipment (100) and DF relay (300)) through omnidirectional transmission. Relying solely on this signal is insufficient for meeting their quality of service (QoS) requirements. However, this received common signal can be leveraged for diversity. It further comprises a UE decoder (110) and a buffer connected to said UE decoder (1 10). In the first transmission phase, cell edge (410) destination nodes receive the common message C[1] and perform decoding to extract the for instance common part c’
[0001] , subsequently stores it in the UE buffer (160).
[0112] Signals described in this description also comprises component defining channel between nodes. But further details are not disclosed herein.
[0113] Referring to figure 4, DF relay (300) comprises a relay receiving means (310) for receiving common message C
[0001] and private message P
[0001] from the base station (200). DF relay (300) comprises a relay first decoder (321 ) for decoding common signal C[1]. Decoded common signal is depicted as common part cA. A relay second decoder (322) decodes private message P
[0001] . cAand pAare acquired. A relay Successive Interference Cancellation (SIC) unit is provided for applying SIC to the received common message C
[0001] and private message P
[0001] and common part cA, leading to the decoding the output of SIC to obtain the combination of private signals for cell edge UEs (102). A relay message splitter (340) is provided for splitting private part pA, private part p2Aand private part p3Aif more than one cell edge (410) information is acquired. A relay encoder (350) is provided for encoding acquired signals. A relay linear precoder (360) is configured to precode signals. DF relay (300) comprises a relay transmitting means (370) for transmitting common message C[2] and private message P[2] using conventional RSMA transmission scheme. Private message (ie P2[2], P3[2]) is sent to each respective cell edge UE (102) directly. Referring to figure 3b, user equipment (100) comprises a UE receiver means (180) suitable for receiving private message P[2] and common message C[2] from DF relay (300). A UE first decoder (121 ) is configured to decode common signal C[2] received from DF relay (300). Decoded signal may be common part c’[2]. In a second embodiment, where common signal C[2] comprises private parts p, decoded signal may comprise p’[2]. In a third embodiment where common signal C
[0001] comprises common parts c and private parts p, thus decoded signal may be private part p’[2] and common part c’[2]. User equipment (100) further comprises a UE diversity unit (130) which is connected to the buffer. In a first embodiment UE diversity unit (130) applies diversity to c’[2] using common part c’[1] and acquires common part c’. Applying diversity reduces SNR of common signal. Since private signal is obtained using common signal, private signal’s SNR is also increases.
[0114] At least one of following diversity techniques may be used: maximal-ratio combining (MRC), equal-gain combiner (EGC).
[0115] User equipment comprises a UE SIC unit (150) for applying SIC on received common message C[2], private message P[2] and common part c’ and decoded by a UE second decoder (122) obtaining private part p’. A UE splitter may be utilized when private part contains more than one private part of different user equipment. A UE combiner combines private part p’ and common part c’ and obtaining message W’.
[0116] In the second embodiment private part p’[2] is acquired by applying successive interface cancellation (SIC) and decoding to common message C[2] and private message P[2] and common part c’. Cell edge UE (102) applies diversity to private part p’[2] using stored private part p’[1] and obtains a common part p’; then cell edge UE (102) applies successive interface cancellation (SIC) to common message C[2] and private message P[2] and common part c’ and obtains private part p’. Cell edge UE (102) combines common part c’ and private part p’ and generates message W’.
[0117] In the third embodiment cell edge UE (102) applies diversity to common part c’[2] using stored common part c’
[0001] and obtains a common part c’. Then cell edge UE (102) applies successive interface cancellation (SIC) and decoding to common message C[2] and private message P[2] and common part c’ and obtains private part p’[2]. Cell edge UE (102) applies diversity to private part p’[2] using stored private part p’
[0001] and obtains a private part p’. Cell edge UE (102) combines the common part c’ and the private part p’ and generates message W’. Subject matter method comprises following steps realized by the system, comprising the steps of:
[0118] - by base station (200) acquiring at least a message W to be sent to at least one cell edge UE (102);
[0119] - by base station (200), dividing message W into private part p and common part c;
[0120] - generating a private message P for cell edge UEs (102) and generating common message C using generated common parts c and generated private parts p;
[0121] - by base station (200) encoding and transmitting said private message P
[0001] and said common message C
[0001] ;
[0122] - by DF relay (300), receiving the private message P
[0001] and the common message C
[0001] ;
[0123] - by DF relay (300), transmitting private message P[2] and common message C[2] to cell edge UE (102);
[0124] - by cell edge UE (102) receiving common message C[1], common message C[2], private message P[2];
[0125] - decoding common message C
[0001] and obtaining and storing private part p’
[0001] and / or common part c’
[0001] ;
[0126] - by cell edge UE (102) applying diversity to a private part p’[2] and / or a common part c’[2] obtained from common message C[2] and private message P[2] using a private part p’
[0001] or to a common part c’
[0001] decoded from stored common message C
[0001] ;
[0127] - generate message W’ using diversified common part c’[2] and private part p’[2] or using diversified common part c’[2] and diversified private part p’[2] or using common part c’[2] and diversified private part p’[2].
[0128] Referring to figure 5, in a first embodiment the method comprises steps of:
[0129] - by base station (200) acquiring at least a message W to be sent to at least one cell edge UE (102);
[0130] - by base station (200), dividing message W into private part p and common part c;
[0131] - by base station (200) combining common parts c and obtaining a common message C using a Rate-Splitting Multiple Access (RSMA) scheme;
[0132] - by base station (200) combining said private parts p and obtaining a private message P using the RSMA scheme;
[0133] - generating a private message P for cell edge UEs (102) and generating common message C using generated common parts c;
[0134] - by base station (200) encoding and transmitting said private message P[1] and said common message C
[0001] ;
[0135] - by DF relay (300), receiving the private message P
[0001] and the common message C
[0001] ; - by DF relay (300), transmitting private message P[2] and common message C[2] to cell edge UE (102);
[0136] - by cell edge UE (102) receiving common message C[1], common message C[2], private message P[2];
[0137] - by cell edge UE (102) acquiring and storing a common part c’
[0001] by decoding common message C
[0001] ;
[0138] - by cell edge UE (102) acquiring a common part c’[2] by decoding common message C[2] and private message P[2];
[0139] - by cell edge UE (102) applying diversity to common part c’[2] using stored common part c’
[0001] and obtaining a common part c’;
[0140] - by cell edge UE (102) applying successive interface cancellation (SIC) and decoding to common message C[2] and private message P[2] and common part c’ and obtaining private part p’;
[0141] - by cell edge UE (102) combining common part c’ and private part p’ and generating message W’.
[0142] Referring to figure 6, in a second embodiment the method comprises steps of:
[0143] - by base station (200) acquiring at least a message W to be sent to at least one cell edge UE (102);
[0144] - by base station (200), dividing message W into private part p and common part c;
[0145] - generating a private message P for cell edge UEs (102) using generated common parts c and generating common message C and generated private parts p;
[0146] - by base station (200) encoding and transmitting said private message P[1] and said common message C
[0001] ;
[0147] - by DF relay (300), receiving the private message P
[0001] and the common message C
[0001] ;
[0148] - by DF relay (300), decoding private message P
[0001] and common message C
[0001] and acquiring private part pAand common part cA; generating private message P[2] using private part pAand generating common message C[2] using common message cA
[0149] - transmitting common message C[2] and private message P[2] to cell edge UE (102);
[0150] - by cell edge UE (102) receiving common message C[1], common message C[2], private message P[2];
[0151] - by cell edge UE (102) acquiring and storing a common part c’[1] and private part p’[1] by decoding and splitting common message C
[0001] ;
[0152] - by cell edge UE (102) acquiring a common part c’[2] by decoding common message C[2] and private message P[2]; - by cell edge UE (102) applying diversity to common part c’[2] using stored common part c’
[0001] and obtaining a common part c’;
[0153] - by cell edge UE (102) applying successive interface cancellation (SIC) and decoding to common message C[2] and private message P[2] and common part c’ and obtaining private part p’[2];
[0154] - by cell edge UE (102) applying diversity to private part p’[2] using stored private part p’
[0001] and obtaining a private part p’;
[0155] - by cell edge UE (102) combining the common part c’ and the private part p’ and generating message W’.
[0156] Referring to figure 7, in a third embodiment the method comprises the steps of:
[0157] - by base station (200) acquiring at least a message W to be sent to at least one cell edge UE (102);
[0158] - by base station (200), dividing message W into private part p and common part c;
[0159] - by base station (200) combining common parts c, private parts p and obtaining a common message C using a Rate-Splitting Multiple Access (RSMA) scheme;
[0160] - by base station (200) combining private parts p and obtaining a private message P using the RSMA scheme;
[0161] - by base station (200) encoding and transmitting said private message P[1] and said common message C
[0001] ;
[0162] - by DF relay (300), receiving the private message P
[0001] and the common message C
[0001] ;
[0163] - by DF relay (300), transmitting private message P[2] and common message C[2] to cell edge UE (102);
[0164] - by cell edge UE (102) receiving common message C[1], common message C[2], private message P[2];
[0165] - by cell edge UE (102) acquiring and storing a common part c’[1] and private part p’[1] by decoding and splitting common message C
[0001] ;
[0166] - by cell edge UE (102) acquiring a common part c’[2] by decoding common message C[2] and private message P[2];
[0167] - by cell edge UE (102) applying diversity to common part c’[2] using stored common part c’
[0001] and obtaining a common part c’;
[0168] - by cell edge UE (102) applying successive interface cancellation (SIC) and decoding to common message C[2] and private message P[2] and common part c’ and obtaining private part p’[2];
[0169] - by cell edge UE (102) applying diversity to private part p’[2] using stored private part p’
[0001] and obtaining a private part p’; - by cell edge UE (102) combining the common part c’ and the private part p’ and generating message W’.
[0170] In a possible embodiment, the step “by DF relay (300), receiving the private message P
[0001] and the common message C
[0001] “ comprises sub steps of:
[0171] - acquiring common part c’
[0001] and private part p’
[0001] by decoding and splitting common message C
[0001] and private message P
[0001] ;
[0172] - applying successive interface cancellation (SIC) and decoding to common message C
[0001] and private message P[1] and common part c’
[0001] and obtaining private part p’
[0001] ;
[0173] - applying diversity to common part c’[1] and private part p’[1] and generating a private message P[2] and common message C[2] using private part p’[1] and common part c’
[0001] .
[0174] 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 data transmission method realized by a system (10) that uses Rate-Splitting Multiple Access (RSMA) scheme for signal transmission, wherein said system (10) comprising a base station (200) providing a cell (400), plurality of user equipment (100) connected to said cell (400) and at least a decode and forward (DF) relay for relaying communication signals transmitted from base station (200) to user equipment (100) (UE) located at cell edge (410) characterized in that comprising following steps:- by base station (200) acquiring at least a message W to be sent to at least one cell edge UE (102);- by base station (200), dividing message W into private part p and common part c;- generating a private message P for cell edge UEs (102) and generating common message C using generated common parts c and generated private parts p;- by base station (200) encoding and transmitting said private message P[1] and said common message C[1 ];- by DF relay (300), receiving the private message P[1] and the common message C[1 ];- by DF relay (300), transmitting private message P[2] and common message C[2] to cell edge UE (102);- by cell edge UE (102) receiving common message C[1], common message C[2], private message P[2];- decoding common message C[1] and obtaining and storing private part p’[1 ] and / or common part c’[1 ];- by cell edge UE (102) applying diversity to a private part p’[2] and / or a common part c’[2] obtained from common message C[2] and private message P[2] using a private part p’[1 ] or to a common part c’[1] decoded from stored common message C[1 ];- generate message W’ using diversified common part c’[2] and private part p’[2] or using diversified common part c’[2] and diversified private part p’[2] or using common part c’[2] and diversified private part p’[2].
2. The data transmission method according to claim 1 , characterized in thatthe step “generating a private message P for cell edge UEs (102) and generating a commonmessage C using generated common parts c and generated private parts p” comprises sub-steps of- by base station (200) combining common parts c and obtaining a common message C using a Rate-Splitting Multiple Access (RSMA) scheme;- by base station (200) combining said private parts p and obtaining a private message P using the RSMA scheme; method further comprising steps of:- by cell edge UE (102) acquiring and storing a common part c’[1 ] by decoding common message C[1 ]; by cell edge UE (102) acquiring a common part c’[2] by decoding common message C[2] and private message P[2];- by cell edge UE (102) applying diversity to common part c’[2] using stored common part c’[1 ] and obtaining a common part c’;- by cell edge UE (102) applying successive interface cancellation (SIC) and decoding to common message C[2] and private message P[2] and common part c’ and obtaining private part p’;- by cell edge UE (102) combining common part c’ and private part p’ and generating message W’.
3. The data transmission method according to claim 1 , characterized in thatVne step “generating a private message P for cell edge UEs (102) and generating a common message C using generated common parts c and generated private parts p” comprises sub-steps of:- by base station (200) combining private parts p and obtaining a common message C using a Rate-Splitting Multiple Access (RSMA) scheme;- by base station (200) combining said common parts c and obtaining a private message P using the RSMA scheme;Comprising the steps realized after the step “by DF relay (300), receiving the private message P[1 ] and the common message C[1 ]”- by DF relay (300), decoding private message P[1] and common message C[1 ] and acquiring private part pAand common part cA; generating private message P[2] using private part pAand generating common message C[2] using common message cA; method further comprising steps of:- by cell edge UE (102) acquiring and storing a private part p’[1] by decoding common message C[1 ];- by cell edge UE (102) acquiring a common part c’ by decoding common message C[2] and private message P[2];- by UE cell edge (102) acquiring private part p’[2] by applying successive interface cancellation (SIC) and decoding to common message C[2] and private message P[2] and common part c’;- by cell edge UE (102) applying diversity to private part p’[2] using stored private part p’[1] and obtaining a common part p’;- by cell edge UE (102) applying successive interface cancellation (SIC) to common message C[2] and private message P[2] and common part c’ and obtaining private part p’;- by cell edge UE (102) combining common part c’ and private part p’ and generating message W’.
4. The data transmission method according to claim 1 , characterized in thatVne step “generating a private message P for cell edge UEs (102) and generating a common message C using generated common parts c and generated private parts p” comprises sub-steps of:- by base station (200) combining common parts c, private parts p and obtaining a common message C using a Rate-Splitting Multiple Access (RSMA) scheme;- by base station (200) combining private parts p and obtaining a private message P using the RSMA scheme; method further comprising steps of:- by cell edge UE (102) acquiring and storing a common part c’[1 ] and private part p’[1 ] by decoding and splitting common message C[1 ];- by cell edge UE (102) acquiring a common part c’[2] by decoding common message C[2] and private message P[2];- by cell edge UE (102) applying diversity to common part c’[2] using stored common part c’[1 ] and obtaining a common part c’;- by cell edge UE (102) applying successive interface cancellation (SIC) and decoding to common message C[2] and private message P[2] and common part c’ and obtaining private part p’[2];- by cell edge UE (102) applying diversity to private part p’[2] using stored private part p’[1] and obtaining a private part p’;- by cell edge UE (102) combining the common part c’ and the private part p’ and generating message W’.
5. The data transmission method according to one of the claims 1 -4, characterized in that the step “by DF relay (300), receiving the private message P[1 ] and the common message C[1]“ comprises sub steps of:- acquiring common part c’[1] and private part p’[1 ] by decoding and splitting common message C[1 ] and private message P[1 ];- applying successive interface cancellation (SIC) and decoding to common message C[1] and private message P[1] and common part c’[1] and obtaining private part p’[1 ];- applying diversity to common part c’[1] and private part p’[1] and generating a private message P[2] and common message C[2] using private part p’[1 ] and common part c’[1 ].
6. A system (10) comprising a base station (200) providing a cell (400), plurality of user equipment (100) connected to said cell (400) and at least a decode and forward (DF) relay for relaying communication signals transmitted from base station (200) to user equipment (100) (UE) located at cell edge (410) capable of realizing a method such as at least in one of the claims 1 -5 characterized in that said base station (200) comprising a BS message splitter (220) configured to split a message W, to be sent to a cell edge UE (102) into private part p and common part c; a BS private combiner (232) configured to generate a private message P for cell edge UEs (102) and a BS common combine (231 ) configured to generate a common message C using generated common parts c and private parts p; a BS encoder (240) for encoding private message P[1] and said common message C[1]; a BS transmitting means (260) configured to transmit the private message P[1 ] and the common message C[1]; the DF relay (300) comprises a relay receiving means (310) configured to receive the private message P[1] and the common message C[1 ] and relay transmitting means (370) for transmitting private message P[2] and common message C[2] to cell edge UE (102); the cell edge UE (102) comprises receiver means (180) configured to receive common message C[1], common message C[2], private message P[2] ; cell edge UE (102) comprises an UE decoder (110) configured to decode common message C[1 ] and obtaining and private part p’[1 ] and / or common part c’[1 ]; an UE buffer (160) for storing common message C[1 ] and obtaining and private part p’[1 ] and / or common part c’[1 ]; comprising a UE first decoder (121 ) and a UE second decoder (122) configured to decode common message C[2] and private message P[2] to obtain a private part p’[2] and / or a common part c’[2] ; a UE diversity unit (130) configured to apply diversity to a privatepart p’[2] and / or a common part c’[2] using common part c’[1] and or private part p’[1 ]; an UE combiner (170) configured to generate message W’ using diversified common part c’[2] and private part p’[2] or using diversified common part c’[2] and diversified private part p’[2] or using common part c’[2] and diversified private part P’[2].
7. The system (10) according to claim 6, characterized in that DF relay (300) comprises a relay first decoder (321 ) and a second relay decoder configured to decode message C[1] and private message P[1 ] for obtaining common part c’[1] and private part p’[1 ]; a relay SIC unit (330) configured to apply successive interface cancellation (SIC) to common message C[1] and private message P[1] and common part c’[1 ]; an diversity means (not shown) configured to apply diversity to common part c’[1] and private part p’[1]; a relay encoder (350) configured to generate a private message P[2] and common message C[2] using private part p’[1 ] and common part c’[1 ].