End point and base station of a telegram-splitting-based communications system with low latency in the downlink

Abstract

Exemplary embodiments create an end point of a wireless communications system, wherein the end point is configured to operate in a first mode and in a second mode, wherein the end point is configured to receive a signal, wherein the signal has information about a first channel access pattern for the first mode, wherein the end point is configured to determine the first channel access pattern for the first mode based on the information about the first channel access pattern, wherein the end point is configured to determine a second channel access pattern for the second mode based on the information about the first channel access pattern, wherein the end point is configured to transmit and / or receive data in the second mode using the second channel access pattern, wherein the first channel access pattern for the first mode permits data transfer with a first latency, wherein the second channel access pattern for the second mode permits data transfer with a second latency, wherein the second latency is lower than the first latency.

Description

[0001] Endpoint and base station of a telegram splitting-based communication system with low latency in the downlink

[0002] Description

[0003] Embodiments of the present invention relate to wireless communication systems, and more particularly, to a wireless communication system that enables transmission of data from a base station to one or more endpoints (downlink) using a low latency time and / or frequency hopping pattern.

[0004] In [1], an ultra narrowband communication system (telegram-splitting ultra narrowband system) based on the telegram splitting method [2] is described, which enables a latency of 3.6 seconds in the uplink (transmission from the endpoint / node to the base station) for ten bytes of payload in standard mode and a latency of less than one (1) second when using a low-delay hop pattern.

[0005] However, according to [1], in the downlink (transmission from the base station to the endpoint / node), it is only possible to transmit a message after an uplink message has been received. This is a significant advantage for battery-powered nodes, as they only need to turn on the receiver once, at a fixed time after an uplink message. This significantly reduces power consumption in the node at the expense of latency, and a battery life of more than ten years can be achieved.

[0006] Typically, such a node sends an uplink message no more frequently than every ten minutes, which automatically results in a resulting latency of ten minutes in the downlink.

[0007] An additional option for a synchronous downlink is described in [2], which transmits beacons at regular intervals, which are received by the nodes. These beacons contain information about which nodes must receive at which times after the beacon in order to receive a downlink transmission. Typical intervals for such beacons are in the range of 30 seconds to five minutes. This allows the latency to be further reduced compared to [1], to approximately 30 seconds to five minutes. However, this comes at the expense of energy consumption and thus battery life, since all nodes must at least always receive and evaluate the beacons.

[0008] However, there are applications that require both sub-one-second uplink latency and sub-one-second downlink latency. However, these nodes typically have a fixed power supply, or the battery doesn't need to last for several years.

[0009] The present invention is therefore based on the object of creating a concept which makes it possible to further reduce the latency in the downlink, whereby the telegram splitting method is to continue to be used in order to maintain the high level of interference immunity.

[0010] This problem is solved by the independent patent claims.

[0011] Advantageous further developments can be found in the dependent patent claims.

[0012] Embodiments provide an endpoint of a wireless communication system, the endpoint being configured to operate in a first mode [e.g., normal latency mode] and a second mode [e.g., low latency mode], [e.g., the second mode enabling transmission and / or reception of data with lower latency than the first mode], the endpoint being configured to receive a signal, the signal comprising information about a first channel access pattern [e.g., normal latency channel access pattern] for the first mode, the endpoint being configured to determine the first channel access pattern for the first mode based on the information about the first channel access pattern, the endpoint being configured to determine a second channel access pattern [e.g., low latency channel access pattern]Low latency channel access pattern] for the second mode based on the information about the first channel access pattern, wherein the endpoint is configured to send and / or receive data in the second mode using the second channel access pattern [e.g., to send an uplink data transmission and / or to receive a downlink data transmission using the second channel access pattern], wherein the first channel access pattern for the first mode enables data transmission with a first latency [e.g., normal latency data transmission or normal latency data transmission], wherein the second channel access pattern for the second mode enables data transmission with a second latency [e.g., low latency data transmission or low latency data transmission], wherein the second latency is lower than the first latency.

[0013] In embodiments, the endpoint is configured to determine the second channel access pattern based solely on the information about the first channel access pattern.

[0014] In embodiments, the endpoint is configured to determine the first channel access pattern from the information of the signal using a first mapping rule, wherein the endpoint is configured to determine the second channel access pattern from the information of the signal using a second mapping rule.

[0015] In embodiments, the information about the first channel access pattern describes a state of a number sequence generator for generating a number sequence, or wherein the information about the first channel access pattern describes a number of a number sequence, wherein the number sequence determines the first channel access pattern.

[0016] In embodiments, the endpoint is configured to transmit and / or receive data in the first mode using the first channel access pattern.

[0017] In embodiments, the first channel access pattern indicates a frequency- and / or time-hopping-based allocation of resource elements usable for communication of the communication system.

[0018] In embodiments, the second channel access pattern indicates a frequency- and / or time-hopping-based allocation of resource elements usable for communication of the communication system.

[0019] In embodiments, the endpoint is configured to send and / or receive data in the first mode in a [e.g., true] subset of the occupancy of resource elements indicated by the first channel access pattern.

[0020] In embodiments, the endpoint is configured to send and / or receive data in the second mode in a [e.g., true] subset of the occupancy of resource elements specified by the second channel access pattern.

[0021] In embodiments, time intervals [e.g., pauses] between immediately consecutive resource elements of the first channel access pattern are greater [e.g., by a factor of two] than time lengths [or durations] of the resource elements of the second channel access pattern.

[0022] In embodiments, a resource element of the second channel access pattern is located at a respective time interval between two immediately consecutive resource elements of the first channel access pattern.

[0023] In embodiments, a reference point [e.g. reference time; e.g. start, middle or end] of a respective resource element of the second channel access pattern has a fixed time interval from a reference point [e.g. reference time; e.g. start, middle or end] of a respective resource element of the first channel access pattern.

[0024] In embodiments, the resource elements of the first channel access pattern are defined temporally relative to a periodic grid [e.g., time grid], wherein a reference point [e.g., reference time; e.g., start, middle, or end] of a respective resource element of the second channel access pattern has a fixed temporal distance from a respective grid point of the periodic grid.

[0025] In exemplary embodiments, the fixed time interval is 136 symbol durations or 57.1 ms.

[0026] In exemplary embodiments, the fixed time interval is 78.75 symbol durations or 33.1 ms.

[0027] In embodiments, a respective resource element of the second channel access pattern is on the same frequency as a respective resource element of the first channel access pattern.

[0028] In embodiments, a respective resource element of the second channel access pattern has a fixed frequency spacing from a respective resource element of the first channel access pattern.

[0029] In embodiments, the endpoint is configured to transmit and / or receive data [e.g., a data packet (e.g., of the physical layer)] divided into a plurality of sub-data packets according to the second channel access pattern, wherein one or more sub-data packets of the plurality of sub-data packets are transmitted and / or received in a resource element of the second channel access pattern. In embodiments, a respective sub-data packet of the plurality of sub-data packets within a respective resource element of the second channel access pattern has a pseudorandom offset in time and / or frequency.

[0030] In embodiments, a data rate of the data transmitted in the second channel access pattern is higher than a data rate of the data transmitted in the first channel access pattern.

[0031] In embodiments, the sub-data packets are channel-coded such that only a true subset of the plurality of sub-data packets is required to successfully decode the data in the case of error-free transmission or a sufficient signal-to-noise ratio.

[0032] In embodiments, the endpoint is configured to receive and decode a true subset of the plurality of sub-data packets to obtain the data, wherein the endpoint is configured not to receive any further sub-data packets of the plurality of sub-data packets if the decoding of the data based on the true subset of the plurality of data packets was successful.

[0033] In embodiments, a plurality of different sub-data packets of the plurality of sub-data packets are sent and / or received in a resource element of the second channel access pattern.

[0034] In embodiments, at least a true subset of the plurality of sub-data packets is repeatedly transmitted, wherein a resource element of the second channel access pattern contains at least an initial transmission of a first sub-data packet and a retransmission of a second sub-data packet, wherein the first sub-data packet and the second sub-data packet are different.

[0035] In embodiments, the data comprises one or more sub-data packets, wherein a transmission of a data packet can only begin in every x-th resource element of the second channel access pattern, where x is a natural number greater than or equal to three [e.g., four, five, six, ten, twelve, or 18]. In embodiments, the endpoint is configured to derive the number x from the information about the first channel access pattern.

[0036] In embodiments, the endpoint is configured to receive the number x from a base station of the communication system [e.g., upon registration with the base station].

[0037] In embodiments, the number x is fixed [e.g. preconfigured (e.g. the information can be the same system-wide and thus known in advance (e.g. at the time of software installation)]

[0038] In embodiments, the data comprises a pilot sequence, wherein the pilot sequence is derived from information [eg, address of the endpoint] identifying the endpoint [eg, unique or non-unique], wherein the endpoint is configured to receive the data when the endpoint is identified [eg, addressed] via the pilot sequence.

[0039] In embodiments, the endpoint is configured to abort receiving the data if the endpoint is not identified via the pilot sequence.

[0040] In embodiments, the information about the first channel access pattern describes a number of a number sequence, wherein the number sequence determines the first channel access pattern, wherein the data is encrypted by means of an encryption, wherein a counter used for the encryption [eg beacon counter] is derived from the first channel access pattern or from the number of the number sequence.

[0041] In embodiments, the counter is a first counter, wherein a second counter [e.g., resource element counter] is further used for encryption.

[0042] In embodiments, the data includes the second counter.

[0043] In embodiments, the endpoint is configured to receive a control signal [e.g., wherein the control signal coordinates access to the resources of the first channel access pattern] [e.g., wherein the control signal is transmitted in specified (e.g., periodic) resource elements of the first channel access pattern], wherein the endpoint is configured to modify [e.g., reset] the second counter in response to receiving the control signal. In embodiments, the control signal is transmitted periodically, wherein the second counter is reset after each transmission of the control signal.

[0044] In embodiments, the endpoint is configured to receive data [e.g., a data packet (e.g., of the physical layer)] divided into a plurality of sub-data packets according to the second channel access pattern, wherein the plurality of sub-data packets are transmitted in a plurality of consecutive resource elements of the second channel access pattern, wherein an order in which the plurality of sub-data packets are transmitted depends on indices of the resource elements of the second channel access pattern in which the plurality of sub-data packets are transmitted, or wherein an order in which the plurality of sub-data packets are transmitted depends on indices of the resource elements of the first channel access pattern immediately preceding the respective resource elements of the second channel access pattern in which the plurality of sub-data packets are transmitted.

[0045] In embodiments, the order in which the plurality of sub-data packets are transmitted is further dependent on an index of a slot within the respective resource elements of the plurality of consecutive resource elements of the second channel access pattern in which the plurality of sub-data packets are transmitted.

[0046] In embodiments, the data comprises a data packet that is transmitted divided into five sub-data packets, wherein the plurality of sub-data packets are transmitted in five consecutive resource elements of the second channel access pattern, wherein an order in which the five sub-data packets are transmitted depends on an index of a resource element of the first channel access pattern that immediately precedes a respective resource element of the second channel access pattern in which a transmission of the five sub-data packets begins, and an index of a slot within the respective resource elements in which the five sub-data packets are transmitted, wherein the order in which the five sub-data packets are transmitted is based on the following table: where in the table each element describes an index of a respective sub-data packet.

[0047] Further embodiments provide a base station of a wireless communication system, wherein the base station is configured to operate in a first mode [e.g., normal latency mode] and in a second mode [e.g., low latency mode], [e.g., wherein the second mode enables transmission and / or reception of data with lower latency than the first mode], wherein the base station is configured to transmit a signal, the signal comprising information about a first channel access pattern [e.g., normal latency channel access pattern] for the first mode, wherein the base station is configured to determine the first channel access pattern for the first mode based on the information about the first channel access pattern, wherein the base station is configured to determine a second channel access pattern [e.g., low latency channel access pattern]Low latency channel access pattern] for the second mode based on the information about the first channel access pattern, wherein the base station is configured to transmit and / or receive data in the second mode using the second channel access pattern [e.g., to receive an uplink data transmission and / or to transmit a downlink data transmission using the second channel access pattern], wherein the first channel access pattern for the first mode enables data transmission with a first latency [e.g., data transmission with normal latency or normal latency data transmission], wherein the second channel access pattern for the second mode enables data transmission with a second latency [e.g., data transmission with low latency or low latency data transmission], wherein the second latency is lower than the first latency.

[0048] In embodiments, the base station is configured to determine the second channel access pattern based solely on the information about the first channel access pattern.

[0049] In embodiments, the base station is configured to determine the first channel access pattern from the information of the signal using a first mapping rule, wherein the base station is configured to determine the second channel access pattern from the information of the signal using a second mapping rule.

[0050] In embodiments, the information about the first channel access pattern describes a state of a number sequence generator for generating a number sequence, or wherein the information about the first channel access pattern describes a number of a number sequence, wherein the number sequence determines the first channel access pattern.

[0051] In embodiments, the base station is configured to transmit and / or receive data in the first mode using the first channel access pattern.

[0052] In embodiments, the first channel access pattern indicates a frequency- and / or time-hopping-based allocation of resource elements usable for communication of the communication system.

[0053] In embodiments, the second channel access pattern indicates a frequency- and / or time-hopping-based allocation of resource elements usable for communication of the communication system.

[0054] In embodiments, the base station is configured to transmit and / or receive data in the first mode in a [e.g., true] subset of the occupancy of resource elements indicated by the first channel access pattern.

[0055] In embodiments, the base station is configured to transmit and / or receive data in the second mode in a [e.g., true] subset of the occupancy of resource elements indicated by the second channel access pattern.

[0056] In embodiments, time intervals [e.g., pauses] between immediately consecutive resource elements of the first channel access pattern are greater [e.g., by a factor of two] than time lengths [or durations] of the resource elements of the second channel access pattern.

[0057] In embodiments, a resource element of the second channel access pattern is located at a respective temporal distance between two immediately consecutive resource elements of the first channel access pattern. In embodiments, a reference point [e.g., reference time; e.g., start, middle, or end] of a respective resource element of the second channel access pattern has a fixed temporal distance from a reference point [e.g., reference time; e.g., start, middle, or end] of a respective resource element of the first channel access pattern.

[0058] In embodiments, the resource elements of the first channel access pattern are defined temporally relative to a periodic grid [e.g., time grid], wherein a reference point [e.g., reference time; e.g., start, middle, or end] of a respective resource element of the second channel access pattern has a fixed temporal distance from a respective grid point of the periodic grid.

[0059] In exemplary embodiments, the fixed time interval is 136 symbol durations or 57.1 ms.

[0060] In exemplary embodiments, the fixed time interval is 78.75 symbol durations or 33.1 ms.

[0061] In embodiments, a respective resource element of the second channel access pattern is on the same frequency as a respective resource element of the first channel access pattern.

[0062] In embodiments, a respective resource element of the second channel access pattern has a fixed frequency spacing from a respective resource element of the first channel access pattern.

[0063] In embodiments, the base station is configured to transmit and / or receive data [e.g., a data packet (e.g., of the physical layer)] divided into a plurality of sub-data packets according to the second channel access pattern, wherein one or more sub-data packets of the plurality of sub-data packets are transmitted and / or received in a resource element of the second channel access pattern.

[0064] In embodiments, a respective sub-data packet of the plurality of sub-data packets within a respective resource element of the second channel access pattern has a pseudorandom offset in time and / or frequency. In embodiments, a data rate of the data transmitted in the second channel access pattern is higher than a data rate of the data transmitted in the first channel access pattern.

[0065] In embodiments, the sub-data packets are channel-coded such that only a true subset of the plurality of sub-data packets is required to successfully decode the data in the case of error-free transmission or a sufficient signal-to-noise ratio.

[0066] In embodiments, the base station is configured to receive and decode a true subset of the plurality of sub-data packets to obtain the data, wherein the base station is configured not to receive any further sub-data packets of the plurality of sub-data packets if the decoding of the data based on the true subset of the plurality of data packets was successful.

[0067] In embodiments, a plurality of different sub-data packets of the plurality of sub-data packets are sent and / or received in a resource element of the second channel access pattern.

[0068] In embodiments, at least a true subset of the plurality of sub-data packets is repeatedly transmitted, wherein a resource element of the second channel access pattern contains at least an initial transmission of a first sub-data packet and a retransmission of a second sub-data packet, wherein the first sub-data packet and the second sub-data packet are different.

[0069] In embodiments, the data comprises one or more sub-data packets, wherein a transmission of a data packet can only start in every x-th resource element of the second channel access pattern, where x is a natural number greater than or equal to three [e.g., four, five, six, ten, twelve, or 18].

[0070] In embodiments, the base station is configured to derive the number x from the information about the first channel access pattern.

[0071] In some embodiments, the number x is fixed [e.g., preconfigured (e.g., the information can be the same system-wide and thus known in advance (e.g., at the time of software installation)]. In some embodiments, the number x is predetermined by the endpoint [e.g., based on the capabilities of the endpoint (e.g., power consumption, computing power)].

[0072] In embodiments, the base station is configured to transmit the data to an endpoint, the data comprising a pilot sequence, the base station being configured to derive the pilot sequence from information identifying the endpoint [e.g., uniquely or non-uniquely] [e.g., address of the endpoint].

[0073] In embodiments, the information about the first channel access pattern describes a number of a number sequence, wherein the number sequence determines the first channel access pattern, wherein the base station is configured to encrypt the data by means of encryption, wherein a counter used for the encryption [eg beacon counter] is derived from the first channel access pattern or from the number of the number sequence.

[0074] In embodiments, the counter is a first counter, wherein the base station is configured to further use a second counter [e.g., resource element counter] for encryption.

[0075] In embodiments, the base station is configured to provide the data with the second counter.

[0076] In embodiments, the base station is configured to transmit a control signal [e.g., wherein the control signal coordinates access to the resources of the first channel access pattern] [e.g., wherein the control signal is transmitted in fixed (e.g., periodic) resource elements of the first channel access pattern], wherein the base station is configured to modify [e.g., reset] the second counter in response to receiving the control signal.

[0077] In embodiments, the control signal is transmitted periodically, wherein the second counter is reset after each transmission of the control signal.

[0078] In embodiments, the base station is configured to transmit data [e.g., a data packet (e.g., of the physical layer)] divided into a plurality of sub-data packets according to the second channel access pattern, wherein the plurality of sub-data packets are transmitted in a plurality of consecutive resource elements of the second channel access pattern, wherein an order in which the plurality of sub-data packets are transmitted depends on indices of the resource elements of the second channel access pattern in which the plurality of sub-data packets are transmitted, or wherein an order in which the plurality of sub-data packets are transmitted depends on indices of the resource elements of the first channel access pattern immediately preceding the respective resource elements of the second channel access pattern in which the plurality of sub-data packets are transmitted.

[0079] In embodiments, the order in which the plurality of sub-data packets are transmitted is further dependent on an index of a slot within the respective resource elements of the plurality of consecutive resource elements of the second channel access pattern in which the plurality of sub-data packets are transmitted.

[0080] In embodiments, the data comprises a data packet that is transmitted divided into five sub-data packets, wherein the plurality of sub-data packets are transmitted in five consecutive resource elements of the second channel access pattern, wherein an order in which the five sub-data packets are transmitted depends on an index of a resource element of the first channel access pattern that immediately precedes a respective resource element of the second channel access pattern in which a transmission of the five sub-data packets begins, and an index of a slot within the respective resource elements in which the five sub-data packets are transmitted, wherein the order in which the five sub-data packets are transmitted is based on the following table: where in the table each element describes an index of a respective sub-data packet.

[0081] Further embodiments provide a method for operating an endpoint of a communication system, wherein the endpoint is configured to operate in a first mode [e.g., normal latency mode] and in a second mode [e.g., low latency mode], [e.g., wherein the second mode enables sending and / or receiving data with lower latency than the first mode]. The method comprises a step of receiving a signal, wherein the signal has information about a first channel access pattern [e.g., normal latency channel access pattern or normal latency channel access pattern] for the first mode. Furthermore, the method comprises a step of determining the first channel access pattern for the first mode based on the information about the first channel access pattern. Furthermore, the method comprises a step of determining the second channel access pattern [e.g., low latency channel access pattern orLow-latency channel access pattern] for the second mode based on the information about the first channel access pattern. The method further comprises a step of transmitting and / or receiving data using the second channel access pattern, wherein the first channel access pattern for the first mode enables data transmission with a first latency [e.g., normal-latency data transmission], wherein the second channel access pattern for the second mode enables data transmission with a second latency [e.g., low-latency data transmission], wherein the second latency is lower than the first latency.

[0082] Further embodiments provide a method for operating a base station of a communication system, wherein the base station is configured to operate in a first mode [e.g., normal latency mode] and in a second mode [e.g., low latency mode], [e.g., wherein the second mode enables transmission and / or reception of data with lower latency than the first mode]. The method comprises a step of transmitting a signal, the signal having information about a first channel access pattern [e.g., normal latency channel access pattern or normal latency channel access pattern] for the first mode. Furthermore, the method comprises a step of determining the first channel access pattern for the first mode based on the information about the first channel access pattern. Furthermore, the method comprises a step of determining the second channel access pattern [e.g., low latency channel access pattern orLow latency channel access pattern] for the second mode based on the information about the first channel access pattern. The method further comprises a step of transmitting and / or receiving data using the second channel access pattern, wherein the first channel access pattern for the first mode enables data transmission with a first latency [e.g., data transmission with normal latency or normal latency data transmission], wherein the second channel access pattern for the second mode enables data transmission with a second latency [e.g., data transmission with low latency or low latency data transmission], wherein the second latency is lower than the first latency. Embodiments of the present invention enable a latency of less than one (1) second in the downlink and, at the same time, utilize the telegram splitting method to enable high interference immunity.

[0083] Embodiments of the present invention are described in more detail with reference to the accompanying figures. They show:

[0084] Fig. 1 is a schematic block diagram of a communication arrangement with a first communication system according to an embodiment of the present invention,

[0085] Fig. 2 is a schematic block diagram of a communication arrangement of two mutually uncoordinated networks, each with a base station and four associated terminals, according to an embodiment of the present invention,

[0086] Fig. 3 shows a diagram showing a division of the frequency band into resources and a frequency- and time-hopping-based allocation of the resources of the frequency band defined by two different channel access patterns, according to an embodiment of the present invention,

[0087] Fig. 4 is a schematic block diagram of a communication system with a base station and a plurality of endpoints, according to an embodiment of the present invention,

[0088] Fig. 5 is a schematic block diagram of a controller for generating a channel access pattern according to an embodiment of the present invention,

[0089] Fig. 6 is a schematic block diagram of a controller for generating a channel access pattern according to another embodiment of the present invention,

[0090] Fig. 7 is a schematic block diagram of a section of the controller according to an embodiment of the present invention, Fig. 8 is a schematic block diagram of a communication system with a base station and two endpoints according to an embodiment of the present invention,

[0091] Fig. 9 is a diagrammatic view of a sequence of points in time defining a temporal position of the resource elements of the channel access pattern, wherein the points in time are pseudorandomly distributed within respective time periods, each of which is defined by an assigned minimum time interval and a predetermined maximum time interval to an immediately preceding point in time of the sequence of points in time, according to an embodiment of the present invention,

[0092] Fig. 10 is a diagrammatic view of the resource elements of the first channel access pattern and the resource elements of the second channel access pattern, wherein the resource elements of the second channel access pattern are located between the resource elements of the first channel access pattern, according to an embodiment of the present invention,

[0093] Fig. 11 is a schematic view of a location of the resource elements of the first channel access pattern and the resource elements of the second channel access pattern, according to an embodiment of the present invention,

[0094] Fig. 12 is a schematic view of a structure of a sub-data packet with (extremely) low latency, according to an embodiment of the present invention,

[0095] Fig. 13 shows a diagrammatic view of the occupancy of a communication channel during a transmission of five sub-data packets with (extremely) low latency, and

[0096] Fig. 14 is a diagrammatic view of an assignment of the sub-data packets according to their indices based on the selected time slot for the first eight resource elements of the second channel access pattern. In the following description of the exemplary embodiments of the present invention, identical or equivalent elements in the figures are provided with the same reference numerals so that their descriptions are interchangeable.

[0097] A. Channel access pattern

[0098] Fig. 1 shows a schematic block diagram of a communication arrangement 100 with a first communication system 102_1, according to an embodiment of the present invention.

[0099] The first communication system 102_1 may include a base station 104_1 and one or more endpoints 106_1-106_n, where n is a natural number greater than or equal to one. In the embodiment shown in Fig. 1, the first communication system 102_1 has four endpoints 106_1-106_4 for illustrative purposes; however, the first communication system 104_1 may equally well include 1, 10, 100, 1,000, 10,000, or even 100,000 endpoints.

[0100] The first communication system 102_1 can be configured to communicate wirelessly in a frequency band (e.g., a license-free and / or authorization-free frequency band, e.g., ISM band) that is used by a plurality of communication systems for communication. The frequency band can have a significantly larger bandwidth (e.g., at least a factor of two) than the reception filters of the subscribers of the first communication system 102_1.

[0101] As indicated in Fig. 1, a second communication system 102_2 and a third communication system 102_3 can be within range of the first communication system 102_1, for example, whereby these three communication systems 102_1, 102_2 and 102_3 can use the same frequency band for wireless communication.

[0102] In embodiments, the first communication system 102_1 can be configured to use different frequencies or frequency channels of the frequency band (e.g. into which the frequency band is divided) in sections (e.g. time slot by time) for communication based on a channel access pattern, regardless of whether they are used by another communication system (e.g. the second communication system 102_2 and / or the third communication system 102_3), wherein the channel access pattern differs from another channel access pattern based on which at least one other communication system of the plurality of other communication systems (e.g. the second communication system 102_2) accesses the frequency band.

[0103] In such a communication arrangement 100, as shown in Fig. 1, the signals of mutually uncoordinated communication systems (e.g., the first communication system 102_1 and the second communication system 102_2) can thus be separated from one another by different channel access patterns, so that mutual disturbance by interference is avoided or minimized.

[0104] For example, subscribers of the first communication system 102_1, such as a base station 104_1 and a plurality of endpoints 106_1-106_4, can communicate wirelessly with each other based on one channel access pattern (e.g., which specifies a frequency-hopping-based occupancy (e.g., of resources) of the frequency band usable for communication of the first communication system 102_1), while subscribers of the second communication system 102_2, such as a base station 104_2 and a plurality of endpoints 106_5-106_8, can communicate wirelessly with each other based on a different channel access pattern (e.g., which specifies a frequency-hopping-based occupancy (e.g., of resources) of the frequency band usable for communication of the second communication system 102_2), wherein the channel access pattern and the other channel access pattern are different (e.g., have an overlap in the resources used of less than 20%, ideally, have no overlap).

[0105] As already mentioned, the communication systems (e.g. the first communication system 102_1 and the second communication system 102_2) are uncoordinated with each other.

[0106] The fact that the communication systems 102_1, 102_2, 102_3 are uncoordinated with each other refers here to the fact that the communication systems do not exchange information among themselves (= between the communication systems) about the respective channel access pattern used, or in other words, that one communication system has no knowledge of the channel access pattern used by another communication system. The first communication system 102_1 is therefore unaware of which channel access pattern is used by another communication system (e.g., the second communication system 102_2).

[0107] Embodiments thus relate to a communication arrangement 100 of mutually uncoordinated and possibly also unsynchronized radio networks (or communication systems) 102_1, 102_2 for data transmission, which access a shared frequency band. In other words, there are at least two radio networks 102_1, 102_2, each operating independently of one another. Both networks 102_1, 102_2 use the same frequency band.

[0108] In exemplary embodiments, it is assumed that only a (small) part of the frequency band is used for each individual data transmission, such as a frequency channel or a sub-frequency channel. For example, the frequency band can be divided into (sub-)frequency channels, with a frequency channel being a true subset of the entire frequency band. The totality of all available frequency channels constitutes the used frequency band. The transmission of a message (data packet) can take place sequentially over a series of different frequency channels, for example, using the telegram splitting method. In this case, exemplary embodiments are particularly useful.

[0109] Networks (or communication systems) 102_1, 102_2 are often arranged in such a way that transmission signals from participants in one network (e.g., communication system 102_2) can also be received by participants in other, nearby networks (e.g., communication system 102_1). Consequently, they appear there as interference signals, which can fundamentally significantly impair the performance of a radio transmission system, as shown in Fig. 2.

[0110] In detail, Fig. 2 shows a schematic view of two mutually uncoordinated networks 102_1, 102_2, each with a base station (BS 1) 104_1, (BS 2) 104_2 and four associated terminals 106_1-106_4, 106_5-106_8. In other words, Fig. 2 shows an exemplary network topology for two networks 102_1, 102_2 with base stations (BS 1) 104_1, (BS 2) 104_2 and four terminals 106_1-106_4, 106_5-106_8. The red dashed arrows 108 symbolize potential interference signals, i.e. the radio subscribers can receive the transmission signals of the subscribers from the other network as interference signals. Depending on the circumstances, a large number of networks may be within reception range of one another, meaning that the subscribers (base stations or terminal devices) may be exposed to a significant number of interference sources from other networks.

[0111] If (as mentioned above) the frequency band is divided into individual, non-overlapping frequency channels as a shared resource, the impact of interference can be significantly reduced. In coordinated networks, each network can be assigned a portion of the frequency band (a set of frequency channels) exclusively, thus minimizing mutual interference. This is not possible in completely uncoordinated networks.

[0112] In embodiments, access to the physical transmission medium (i.e. the physical radio channel) in each network is therefore designed such that at least one of a) the channel access, i.e. the frequency and time occupancy of the radio channel, in a network has as little overlap in time and frequency as possible with the channel access in other networks of the same standard (high degree of “orthogonality”), b) the channel access has a (pseudo-)random character within desired specifications (e.g. average access frequency per time) (“randomness”), c) as far as avoidable according to the specifications, no longer sequences of (in time and frequency) identical channel access occur between networks (“avoidance of systematic overlaps”), d) all frequency channels within the frequency band are used as evenly as possible in order to achieve the highest possible frequency diversity and, if necessary,to ensure compliance with official regulatory requirements (“equal distribution of frequency channel usage”), e) information on frequency and time occupancy of the radio channel, e.g. for a.

[0113] Network new participants with the least possible

[0114] signaling effort (“reduction of

[0115] Signaling information”) is fulfilled.

[0116] In simple terms, in embodiments, mutual interference between several networks (inter-network interference) is reduced by channel access to the shared frequency band being different in frequency and time, preferably as “orthogonal” as possible and with (pseudo-)random character.

[0117] For the sake of illustration, it is assumed below that in addition to the division of the frequency band into discrete frequency channels (indices c0, c1, c2,...), a temporal discretization of the accesses within each network also takes place. The associated temporal resources are referred to as time slots and are provided with the indices t0, t1, t2,... in Fig. 3. However, both requirements (discretization in frequency and time) are not necessary prerequisites for the application of exemplary embodiments. In detail, Fig. 3 shows a diagram of a division of the frequency band into resources as well as a frequency- and time-hopping-based allocation of the resources of the frequency band defined by two different channel access patterns. The ordinate describes the frequency channel indices and the abscissa the time slot indices.

[0118] For example, subscribers of the first communication system 102_1 can communicate wirelessly with each other based on the channel access pattern 110_1, which indicates a frequency-hopping-based allocation of resources of the frequency band usable for the communication of the first communication system 102_1, while subscribers of the second communication system 102_2 can communicate wirelessly with each other based on a different channel access pattern 110_2, which indicates a frequency-hopping-based allocation of resources of the frequency band usable for the communication of the second communication system 102_2, wherein the channel access pattern and the other channel access pattern are different (e.g., have an overlap of less than 20%, ideally have no overlap).

[0119] In other words, Fig. 3 shows, in the form of a grid, an overview of all fundamentally available resources in frequency and time (schematic representation of the frequency channels and time slots as well as exemplary channel access patterns), wherein an individual resource element in the first communication network 102_1 is determined by assigning a frequency channel index and a time slot index. By way of example, the resources that can be occupied by the first communication network 102_1 are the resource elements identified by reference numeral 112_1. The set of all resources that can be occupied within a communication network represents a channel access pattern 110_1. For the first communication network 102_1, these are all resource elements identified by reference numeral 112_1, which are connected by arrows. In an equivalent manner, the channel access pattern of a further communication network (e.g., the second communication network 102_2) is shown in Fig.3 is entered as an example (all resource elements identified by reference numeral 112_2, which are connected by arrows), which is not anchored in the same frequency and time grid as the first communication network 102_1 (resource elements are shifted in frequency and time from the basic grid of the first communication network 102_1).

[0120] It is important to distinguish between

[0121] • all resource elements that are fundamentally (maximally) available, ie the total set of all resource elements from which the channel access pattern selects a suitable subset (in Fig. 3, for example, all elements of the grid), • all resource elements that are actually included in the channel access pattern (in Fig. 3, all resource elements marked with reference numeral 112_1) and

[0122] • the number of resource elements (of the channel access pattern) that are actually used in the network for data transmission (for example, with a low data volume, only every third resource element in the channel access pattern could actually be used).

[0123] The design of the channel access pattern therefore also means determining the actively usable resource pool for this communication network (or communication system).

[0124] The following describes embodiments of base stations, endpoints, and / or communication systems that use channel access patterns for communication that satisfy at least one of the above-mentioned criteria a) to e). Furthermore, the following describes embodiments of generating such channel access patterns.

[0125] A.1. Base station, endpoint and communication system

[0126] Fig. 4 shows a schematic block diagram of a communication system 102 with a base station 104 and a plurality of endpoints 106_1-106_4, according to an embodiment.

[0127] As shown in Fig. 4, in one embodiment, the communication system 102 may include a base station and four endpoints 106_1-106_4. However, the present invention is not limited to such embodiments; rather, the communication system may include one or more endpoints 106_1-106_n, where n is a natural number greater than or equal to one. For example, the communication system may include 1, 10, 100, 1,000, 10,000, or even 100,000 endpoints.

[0128] The subscribers (= base station 104 and endpoints 106_1-106_4) of the communication system shown in Fig. 4 use a frequency band (e.g., a license-free and / or authorization-free frequency band, e.g., ISM band) for mutual communication, which frequency band is used by a plurality of communication systems for communication, as explained above with reference to Figs. 1 to 3. The communication system 102 operates in an uncoordinated manner with respect to the other communication systems that use the same frequency band. In embodiments, the base station 104 can be configured to transmit a signal 120, wherein the signal 120 comprises information about a channel access pattern 110, wherein the channel access pattern indicates a frequency- and / or time-hopping-based occupancy (e.g., of resources) of the frequency band that can be used for the communication of the communication system 102 (e.g.,a temporal sequence of frequency resources usable for the communication of the communication system (e.g. distributed over the frequency band), wherein the information describes a state of a number sequence generator for generating a number sequence, wherein the number sequence determines the channel access pattern.

[0129] For example, the state of the number sequence generator can be an internal state of the number sequence generator, whereby a number in the number sequence can be derived from the internal state of the number sequence generator. Based on the internal state of the number sequence generator, internal states of the number sequence generator that follow the internal state of the number sequence generator can also be determined, from which the following numbers in the number sequence can also be derived. For example, the number in the number sequence can be derived directly from the internal state of the number sequence generator (e.g. state = number), e.g. when implementing the number sequence generator as a counter, or via a mapping function, e.g. when implementing the number sequence generator as a shift register, possibly with feedback.

[0130] In embodiments, at least one of the endpoints 106_1-106_4 may be configured to receive the signal 120 with the information about the channel access pattern 110 and to determine the channel access pattern 110 based on the information about the channel access pattern, wherein the information describes a state of a number sequence generator for generating a number sequence, wherein the number sequence determines the channel access pattern.

[0131] For example, the base station 104 and / or at least one of the endpoints 106_1-106_4 may be configured to pseudorandomly determine the channel access pattern depending on the state of the number sequence generator, such as using a pseudorandom mapping function.

[0132] Furthermore, the base station 104 and / or at least one of the endpoints 106_1-106_4 can be configured to pseudorandomly determine the channel access pattern depending on individual information of the communication system (e.g., intrinsic information of the communication system, such as a network-specific identifier).

[0133] Exemplary embodiments of the generation of channel access patterns are described below. The channel access patterns are generated by the base station 104 and can be determined based on the signal containing the information 120 about the channel access pattern from at least one (or all) of the endpoints 106_1-106_4 shown in Fig. 4, for example, by a controller (control device, control unit) 130 implemented in the base station 104 and / or in the endpoints 106_1-106_4. The channel access patterns are specified (exclusively) by the base station 104, while the endpoints 106_1-106_4 only "know" the channel access pattern, i.e., they generate it using the same method as the base station 104.

[0134] The following description assumes a radio transmission system (or a communication arrangement) with several independent, uncoordinated communication networks whose participants are within mutual reception range, so that transmission signals from participants in one network can potentially be considered interference signals for participants in other networks. For the application of the exemplary embodiments, it is not necessary for information (data or signaling information) to be exchanged between different networks. It is also irrelevant whether the networks are synchronized with each other in terms of time and / or frequency.

[0135] Furthermore, it is assumed that within each network there is a coordinating entity (hereinafter referred to as the "base station") that can transmit information about the channel access pattern used within the network to the non-coordinating participants in the network (hereinafter referred to as "end devices" or "endpoints"). This information can be transmitted, for example, via regularly transmitted beacons, but can also be transmitted at irregular intervals or, if necessary, specifically to individual end devices or groups of end devices.

[0136] Furthermore, it is assumed that the entire frequency band available for transmission is divided into a large number of individual frequency channels, each of which can be accessed individually or in subsets (groups of frequency channels).

[0137] Without limiting generality and for clarity, the following discussion assumes that within each network, a fixed, discrete time frame exists at which channel access can occur (see also Fig. 3). Channel access in the form of transmitting a signal can occur both by end devices and by the base station. However, channel access does not necessarily have to occur in a resource designated for this purpose in the channel access pattern, for example, if no data or other information is pending transmission.

[0138] Fig. 5 shows a schematic block diagram of a controller 130 for generating a channel access pattern, according to an embodiment of the present invention.

[0139] As can be seen in Fig. 5, the controller 130 may include a memory 132, a periodic number generator 134 for generating a periodic number sequence Z, a randomizing allocator 136 and a frequency / time allocator 138.

[0140] The memory (e.g., a register) 132 can be configured to hold a network-specific identifier ID 140, e.g., an (individual) bit sequence that does not change. The periodic number generator 134 can be configured to provide its state 142 or a number 142' derived from its state of the periodic number sequence. The randomizing assigner 136 can be configured to determine a pseudorandom number R 144 depending on the state 142 of the number sequence generator 134 or the number 142' derived therefrom of the periodic number sequence and the network-specific identifier ID 140. The frequency / time assigner 138 can be configured to determine frequency information f 146 and time information 1 148 based on the pseudorandom number R 144.For example, the frequency information f 146 and the time information 1 148 can describe or define a frequency channel and a time slot (or a frequency channel index and a time slot index) and thus a resource of the channel access pattern.

[0141] For example, as indicated in Fig. 4, the controller 130 may be implemented in the base station 104 and / or in the one or more endpoints 106_1-106-4 to calculate the individual (or network-specific) channel access pattern used by the communication system 102.

[0142] In other words, Fig. 5 shows the basic structure for generating channel access patterns according to an embodiment of the present invention. The channel access patterns are generated iteratively, meaning that the blocks shown in Fig. 5 are called once per generation of a single piece of channel access information. Thus, by calling N times, a channel access pattern with N channel accesses is generated.

[0143] The function of the subblocks is explained in detail below. The term "number" is used. This generally refers to discrete information that can be represented in various ways (e.g., in decimal form, as a binary sequence, or similar).

[0144] Network-specific identifier “ID”

[0145] The network-specific identifier is a fixed number that is determined by an external entity (e.g., during network configuration or the coordinating base station). Ideally, it varies from network to network. For example, it could be a unique, sufficiently long base station ID, a unique network ID, or a sufficiently long hash of each of them. This value is fixed and, in the arrangement shown, is the only one that does not vary from call to call.

[0146] Periodic number generator “Z”

[0147] The periodic number generator 134 generates a periodically repeating sequence of numbers Z with the periodicity P. It has an internal state S n , from which the next generated number and the next internal state S n+i can be uniquely determined. The crucial feature is that the entire periodic sequence for any given journal can be derived from a single internal state (which is present for any given journal). A simple example is a modulo-P counter, which periodically delivers the number sequence 0, 1, 2... (P-1). Another example is a deterministic random number generator (pseudo-random number generator), e.g., implemented as a feedback shift register (LFSR). A third example is a finite field (Galois field) with P elements.

[0148] Randomizing assigner

[0149] The randomizing mapper 136 generates an output number R from the two input numbers ID and Z, i.e., R=map_rand(\D, Z), where map_rand represents the mapping function. The mapping is as random as possible, i.e., a mathematically correlated input sequence (consisting of ID, Z) generates an output sequence R that is as uncorrelated as possible.

[0150] Examples of implementation of a random assignment are

[0151] • Concatenation of the two input numbers

[0152] • the application of a cyclic redundancy check (CRC) to the input variables ID, Z, which leads to the number R and has a randomizing character,

[0153] • the application of a hash function

[0154] • the use of encryption, e.g. AES encryption, where the associated key is known to all authorized participants and thus also represents a method for implementing “transport layer security” (TLS for short).

[0155] The sequence of elements of the number R is pseudorandom in nature according to the above criteria. It should vary from network to network to avoid overlaps in channel access patterns as much as possible. t-allocator

[0156] The frequency / time allocator 138 assigns a 2-tuple of frequency information (radio frequency f) and time information (access time t) to each input number R using a mapping, i.e., (f,t)=map_ff(R), where "map_ff" represents the mapping function. While the sequence of frequencies can, in principle, be arbitrary within the specified frequency band, the times must be monotonically increasing from call to call, since "jumps back" in time are not permitted.

[0157] Of particular importance is the case where channel access is discretized in frequency and time directions (as described above), i.e., in the form of discrete frequency channels and discrete time slots. In this case, the frequency / time allocator assigns a 2-tuple of frequency channel index fi and time slot index ti to each input number R, i.e., (fi,ti)=map_ff(R). The time slots are indexed in ascending chronological order, since "backwards" in time are not permitted.

[0158] The sequence of 2-tuples (f,t) or (fi, ti) is based on the sequence of elements of R and defines the channel access pattern. The precise design of the frequency / time allocator, together with the probability function of the number R, determines the channel access statistics. and predictability

[0159] The arrangement shown in Fig. 5 generates a channel access pattern that depends on both a time-invariant, network-specific identifier and a state-dependent (and thus time-varying) periodic number generator (periodicity P). The network-specific identifier ensures that networks with different network-specific identifiers always generate different sequences of R, even if their number generators are in the same state. This ensures that different networks do not generate identical channel access patterns and thus, in the worst case, experience a "permanent collision" of channel accesses.

[0160] To determine the channel access pattern used in the network, a terminal device requires both the network-specific identifier and the current state of the periodic number generator.

[0161] The end device receives the network-specific identifier upon initial registration with the network. This is preferably transmitted via beacon signals regularly transmitted by the base station and made accessible to all authorized end devices. Alternatively, the network-specific identifier can also be made known to the end device during initial configuration (at delivery), i.e., before initial network use. Alternatively, the network-specific identifier can also be transmitted to the respective subscriber in a separate message.

[0162] The state of the periodic number generator can be transmitted either in a regular beacon signal and / or in dedicated state signaling resources. A number generator with periodicity P has P internal states, so

[0163] Transmission of the respective status gj tsmust be transferred. The per

[0164] The amount of information (number of bits) transmitted for status signaling can thus be controlled on demand by the selected periodicity of the number generator.

[0165] The information transmitted for status signaling can be transmitted in the form of multiple pieces of information, with transmission occurring at different frequencies. For example, if the periodic number generator (Z) is a counter, the most significant bits (MSBs) of the counter could be transmitted separately from the least significant bits (LSBs) and at a different frequency (e.g., less frequently). Even if it is not a counter, the entire status information could be transmitted in the form of multiple pieces of status information with different transmission frequencies.

[0166] Due to the periodicity of the number generator, a terminal device that knows the state of the number generator at at least one point in time can determine the entire channel access pattern for any point in time / time slot in the future. This allows the terminal device, for example, to deactivate the transmit / receive unit in a power-saving idle state and, upon subsequent activation of the transmit / receive unit, to predict the then-valid section of the channel access pattern from the last previously known state. The base station can thus transmit the state information at comparatively long intervals.

[0167] In summary, the method described here has the advantage that the combination of a network-specific identifier and a periodic number generator creates a comparatively large state space for the (pseudo-random) number R. This prevents the channel access patterns of networks with different network-specific identifiers from being identical, thus minimizing systematic collisions between channel accesses of different, uncoordinated networks. This proves particularly advantageous in the Telegram Splitting Multiple Access (TSMA) method.

[0168] Advantageous features of the frequency-time mapper are explained in more detail in the following sections.

[0169] Another embodiment of the controller

[0170] According to Fig. 5 and the above description, a periodic number generator 134 is required. This is replaced in the following embodiment as follows.

[0171] Real radio networks are often operated with a beacon signal that is transmitted regularly. Each beacon transmission can be assigned a counter that corresponds to a beacon sequence index. This beacon sequence index is referred to here as the "beacon index." It is also common for time-slot-based systems to assign time slots a time-slot index counter (which ascends in time) (see also Fig. 3). This is referred to here as the "time-slot index." The beacon index is reset to zero at certain intervals specified by the system, thus exhibiting a periodicity. The same applies to the time-slot index (which, for example, starts again at zero after a beacon transmission).

[0172] Fig. 6 shows a schematic block diagram of a controller 130 for generating a channel access pattern, according to an embodiment of the present invention.

[0173] The controller 130 may include a memory 132, a first buffer 135_1, a second buffer 135_2, a randomizing mapper 136, and a frequency / time mapper 138.

[0174] The memory (e.g., a register) 132 can be configured to hold a network-specific identifier ID 140, e.g., an (individual) bit sequence that does not change. The first buffer (e.g., a register) 135_1 can be configured to hold a periodic beacon index Z1 143_1. The second buffer (e.g., a register) 135_2 can be configured to hold a periodic time slot index Z2 143_2. The randomizing allocator 136 can be configured to determine a pseudorandom number R 144 depending on the periodic beacon index Z1 143_1, the periodic time slot index Z2 143_2, and the network-specific identifier ID 140. The frequency / time allocator 138 may be configured to determine frequency information f 146 and time information t 148 based on the pseudorandom number R 144.For example, the frequency information f 146 and the time information 1 148 can describe or define a frequency channel and a time slot (or a frequency channel index and a time slot index) and thus a resource of the channel access pattern.

[0175] In other words, Fig. 6 shows a modified basic structure for generating channel access patterns with a beacon index and a time slot index. Fig. 6 shows an embodiment in which, compared to the embodiment shown in Fig. 5, the periodic number generator (output Z) 134 has been replaced by the two blocks "periodic beacon index" (output Z1) 135_1 and "periodic time slot index" (output Z2) 135_2. All other blocks are functionally unchanged (the randomizing allocator now has three inputs). The controllers 130 shown in Figs. 5 and 6 enable the generation of network-specific channel access patterns, which have at least one of the following properties:

[0176] • The channel access patterns contain as few overlapping subsequences as possible,

[0177] • there is (e.g. in areas with high network density) a large pool of channel access patterns,

[0178] • the channel access patterns are designed to have a very high periodicity,

[0179] • the channel access patterns lead (if appropriate requirements exist) to an averagely uniform use of the available frequency channels,

[0180] • the signaling of the applied pattern is carried out by the coordinating instance with as little signaling information as possible, and

[0181] • Terminal devices can determine the content of the channel access pattern at any future point in time even after receiving the signaling of the channel access pattern completely once (this allows terminal devices, for example, to take longer reception breaks for energy-saving reasons and, when switched on again, to still determine the then valid channel access pattern on the basis of information received before the reception break).

[0182] A.2. Control of channel access in the frequency domain

[0183] To simplify the following illustration, it is assumed that the frequency range (or frequency band) is divided into discrete frequency channels and that transmission is carried out using the TSMA method.

[0184] Mobile radio channels typically exhibit signal attenuation that varies with frequency. If a data packet is transmitted as several sub-packets according to the TSMA method, and the underlying mobile radio channel is unknown at the transmitter, the average transmission error rate can be reduced or even minimized by distributing the individual sub-packets across the entire frequency range (utilizing frequency diversity).

[0185] For this reason, it can be advantageous (particularly if a data packet consists of only a few partial data packets) to ensure that the frequency channels on which the partial data packets are transmitted have a certain (minimum) distance in the frequency range relative to each other.

[0186] Since the channel access pattern within a network significantly determines the frequency hopping behavior in TSMA, a suitable procedure can be used to ensure that there is a minimum distance between two consecutive frequency channels of the channel access pattern.

[0187] In embodiments, the frequency / time allocator 138 (see Fig. 5 or 6) may therefore be configured to determine frequency information f and time information t based on the pseudorandom number R, wherein the frequency information f indicates a distance between two consecutive frequency channels.

[0188] The frequency / time allocator 138 in Fig. 5 or 6, which determines absolute frequency channels independently from access to access on the basis of the pseudorandom number R, can thus alternatively also determine distances between two consecutive frequency channels.

[0189] Fig. 7 shows a schematic block diagram of a section of the controller 130, according to an embodiment. As can be seen in Fig. 7, the frequency / time allocator 138 (see Fig. 5 or 6) can be configured to determine frequency information and time information based on the pseudorandom number R, wherein the frequency information includes a distance Afi n between two consecutive frequency channels.

[0190] As can also be seen in Fig. 7, the controller 130 may have an imager 150, which may be configured to determine the distance Afi nbetween two consecutive frequency channels to a frequency channel index fi, for example by a combiner (e.g. adder) 152 and a delay element 154.

[0191] In other words, Fig. 7 shows the generation of frequency jumps with minimum and / or maximum jump widths. Fig. 7 illustrates that the frequency / time allocator 138 of Fig. 5 or 6 is now replaced by a frequency difference / time allocator 138, which no longer delivers absolute frequency channel indices at its immediate output, but rather frequency channel index differences.

[0192] By using a suitable mapping function (Afi,t)=map_Aft(R) in the frequency difference / time allocator, it can be ensured that only frequency channel index jumps Afi n =fi n +i-fin (from channel access n to channel access n+1), which are within a desired range, e.g. Afi m ax^Afi>Afi min for Afi>0 and Afi ma x^(- Afi)>Afi m in for Afi<0. There are numerous methods for implementing such a restriction, which are not themselves the subject of the invention.

[0193] The following shows how one or more participants of a communication system 102 can transmit data using the channel access pattern.

[0194] B. Channel access via the channel access pattern

[0195] Fig. 8 shows a schematic block diagram of a communication system 102 with a base station 104 and two endpoints 106_1-106_2, according to an embodiment of the present invention.

[0196] The communication system 102 shown in Fig. 8 comprises, by way of example, a base station 104 and two endpoints 106_1-106_2. However, the present invention is not limited to such embodiments; rather, the communication system 102 may comprise one or more endpoints 106_1-106_n, where n is a natural number greater than or equal to one. For example, the communication system may comprise 1, 10, 100, 1,000, 10,000, or even 100,000 endpoints.

[0197] As already explained in detail above (see, for example, Fig. 4), the participants (= base station 104 and endpoints 106_1-106_2) of the communication system use a frequency band (e.g., a license-free and / or authorization-free frequency band, e.g., ISM band) for mutual communication, which frequency band is used by a plurality of communication systems for communication. The communication system 102 operates in an uncoordinated manner with respect to the other communication systems that use the same frequency band.

[0198] As also explained in detail above, the base station 104 is configured to transmit a signal 120, wherein the signal 120 comprises information about a channel access pattern 110, wherein the channel access pattern 110 indicates a frequency- and / or time-hopping-based occupancy of resource elements of the frequency band usable for the communication of the communication system 102, while the endpoints 106_1-106_2 are configured to receive the signal 120 and to determine the channel access pattern 110 based on the information about the channel access pattern (see, for example, Figs. 5 and 6). A resource element can comprise one or more time slots and / or one or more frequency channels.

[0199] For mutual communication, ie for mutual transmission of data, the participants (e.g. base station 104 and endpoint 106_1 ) can use a proper subset of the resource elements specified by the channel access pattern 110, such as i resource elements of the channel access pattern, where i is a natural number greater than or equal to three, such as 3, 4, 5, 10, 15 or 18.

[0200] In detail, in embodiments, base station 104 may be configured to transmit and / or receive data 160 (e.g., a signal including data 160) using a true subset of the resource element occupancy specified by the channel access pattern. Accordingly, endpoint 106_1 may be configured to transmit and / or receive data 160 (e.g., a signal including data 160) using a true subset of the resource element occupancy specified by the channel access pattern.

[0201] The data can be divided into a plurality of sub-data packets and transmitted using the channel access pattern. A sub-data packet can be transmitted in each resource element of the channel access pattern, for example, if the resource element comprises a time slot and / or a frequency channel. Of course, multiple sub-data packets can also be transmitted per resource element of the channel access pattern, for example, if the resource element comprises multiple time slots and / or frequency channels.

[0202] For example, the data (e.g. a data packet or telegram) can be divided into j sub-data packets, where j is a natural number greater than or equal to three, such as 3, 4, 5, 10, 15 or 18. To transmit the sub-data packets, j = i resource elements of the channel access pattern can be used, so that one sub-data packet of the plurality of sub-data packets is transmitted in each resource element. Of course, more than one sub-data packet of the plurality of sub-data packets can also be transmitted per resource element, such as two, three or four sub-data packets. On the receiver side, the sub-data packets or at least a real subset of the sub-data packets can be reassembled or combined to obtain the data.To further increase the interference immunity, the resource elements of the channel access pattern and thus also the sub-data packets transmitted in the respective resource elements of the channel access pattern can have a pseudo-random offset in time, as explained below with reference to Fig. 9.

[0203] In detail, Fig. 9 shows a diagrammatic view of a sequence of times 180 that define a temporal position of the resource elements 112 of the channel access pattern 110, wherein the times 180 are pseudorandomly distributed within respective time periods 182, each of which is defined by an assigned minimum time interval 184 and a predetermined maximum time interval 186 to an immediately preceding time of the sequence of times 180, according to an embodiment of the present invention. In Fig. 9, the abscissa describes time. The times can coincide with temporal reference points of the resource elements 112. In Fig. 9, it is assumed, for example, that the temporal reference points (or reference times) are centers of the respective resource elements.However, the temporal reference points can also be the start or end of the resource elements or any other point in time within a resource element.

[0204] Sections A and B describe a communication system in which a beacon is transmitted at specific intervals, and downlink messages can be sent to the nodes between the beacons. Due to its advantageous properties, this approach also uses the telegram splitting method, in which there is a transmission pause between individual sub-data packets. For this purpose, a so-called resource element grid (in other words, a template for the sub-data packets) is used, from which the location of the sub-data packets can be derived (e.g., with the help of additional parameters such as the BS-EUI and a counter).

[0205] The following describes how the use of a second channel access pattern can further reduce the latency in the downlink (i.e. for transmissions from the base station to one or more nodes).

[0206] C. Additional channel access pattern with aerina latency

[0207] In embodiments, the channel access pattern described in sections A and B may be a first channel access pattern. The participants (e.g., base station 104 and endpoint 106_1) of the communication system may be configured to operate in a first mode (e.g., normal latency mode) and in a second mode (e.g., low latency mode). The first channel access pattern for the first mode may be determined based on the information about the first channel access pattern, for example, as described above in section A.

[0208] The first channel access pattern can enable data transmission with normal latency.

[0209] According to the concept of the present invention, in order to realize data transmission with a low latency, a second channel access pattern is introduced for the second mode, which enables data transmission with a lower latency than the first channel access pattern.

[0210] In embodiments, the second channel access pattern may also be determined based on the information about the first channel access pattern, which is transmitted by the base station via the signal 120 anyway, so that no additional overhead is incurred for the second channel access pattern.

[0211] For example, the first channel access pattern can be determined from the information about the first channel access pattern via a first mapping rule, for example as described above in Section A, while the second channel access pattern can be determined from the information about the first channel access pattern via a second mapping rule, wherein the first mapping rule and the second mapping rule are different.

[0212] In embodiments, a resource element of the second channel access pattern may comprise one or more time slots and / or one or more frequency channels.

[0213] In embodiments, a sub-data packet can be transmitted in each resource element of the second channel access pattern, for example, if the resource element comprises a time slot and / or a frequency channel. Of course, multiple sub-data packets can also be transmitted per resource element of the channel access pattern, for example, if the resource element comprises multiple time slots and / or frequency channels, wherein one sub-data packet can be transmitted per time slot / frequency channel. Detailed embodiments of the present invention are described in more detail below.

[0214] C.1 Exploitation of the channel access pattern from sections A and B for further communication

[0215] Achieving a latency of less than one (1) second traditionally requires a node (or endpoint of the communication system) to check for a new message with the receiver at least once per second. As mentioned above, this significantly increases power consumption, making it feasible only for nodes with large batteries and shorter battery lifespans, or for nodes with external power supplies.

[0216] The system described in sections A and B uses a resource grid with average intervals between sub-data packets of approximately 50 ms to 500 ms. The maximum transmission time of a sub-data packet is approximately 25 ms.

[0217] This results in pauses between the sub-data packets during which no transmission takes place. These pauses are often used in embodiments for transmissions that require a latency of less than one (1) second. Nodes that support this "ultra-low-delay" mode must therefore be registered in the system described in Section B so that they know the position of the resource grid, the resource elements (RE; designated by reference numeral 112 in Fig. 9), and thus also the pauses. During these pauses, the transmission of the telegram with extremely low latency (ultra-low-delay telegram) can then begin at a defined time offset after the resource grid or after the actual transmission time slot (e.g. transmission time of the sub-data packet or the resource element according to Section B, also called a radio burst).

[0218] Fig. 10 shows a diagrammatic view of the resource elements 112 of the first channel access pattern and the resource elements 192 of the second channel access pattern, wherein the resource elements 192 of the second channel access pattern are located between the resource elements of the first channel access pattern, according to an embodiment of the present invention. In Fig. 10, the abscissa represents time. In other words, Fig. 10 shows an exemplary scheme for accommodating ultra-low-delay sub-data packets between existing sub-data packets according to Section A.

[0219] In embodiments, a temporal position of the resource elements 112 of the first channel access pattern 112 can be defined relative to a periodic grid 188. Thus, as indicated in Fig. 10, the resource elements 112 of the first channel access pattern can have a pseudorandom offset in time with respect to the periodic grid 188, e.g., such that the resource elements 112 of the first channel access pattern lie within predetermined time ranges around the respective grid positions of the periodic grid 188.

[0220] For example, a temporal position of the resource elements 112 of the first channel access pattern can be defined by a sequence of points in time relative to the periodic grid, wherein the points in time of the sequence of points in time are defined such that time intervals between immediately consecutive points in time of the sequence of points in time are distributed pseudorandomly between a minimum time interval and a maximum time interval, and such that the points in time of the sequence of points in time lie within predetermined time ranges around the respective grid positions. Temporal reference points of the resource elements 112, such as the beginning, middle, or end of the respective resource elements 112, can coincide with the points in time of the sequence of points in time.

[0221] In the exemplary embodiment shown in Fig. 10, it is assumed, by way of example, that the distance between grid points of the periodic grid is 260 symbol durations, with a first resource element having a temporal offset from the periodic grid of +58 symbol durations, while a second resource element has a temporal offset from the periodic grid of -58 symbol durations. However, the invention is not limited to such exemplary embodiments. Rather, the distance between grid points of the periodic grid can also assume entirely different values. As non-limiting examples, values ​​of 10, 20, 30, 40, 50, 100, 200, 300, 400, 500, 1000, etc. symbol durations are mentioned here, or value ranges from 50 to 500 or 10 to 1000 symbol durations. The temporal offset from the periodic grid can also assume entirely different values.

[0222] In other words, Fig. 10 shows a schematic view of the insertion of new transmission time slots (LL-RE (LL-RE = low-latency resource elements)) between the resource elements (RE (RE = (resource elements); transmission times of the sub-data packets according to section B), as well as the resource grid. In Fig. 10, the position of the transmission time slots (LL-RE) with (extremely) low latency is made dependent on the resource grid as an example. Of course, it would also be possible to make the transmission time slots (LL-RE) with (extremely) low latency dependent on the times of the sub-data packets according to section B.

[0223] In embodiments, the location of the transmission time slots with extremely low latency is made dependent on another system / transmission mode of the system and therefore no further synchronization of the participants is necessary for the mode with extremely low latency and no further data needs to be transmitted for coordination.

[0224] In embodiments, since the system described in sections A and B uses the telegram splitting method with pseudo-random times and frequencies, these pseudo-random times and / or frequencies can also be used for the ultra-low-delay sub-data packets, since this still provides immunity to interference from the random time jitter and / or offset in the frequency.

[0225] Figure 11 shows a schematic view of a location of resource elements 112 of the first channel access pattern (e.g., channel access pattern with normal latency) and resource elements 192 of the second channel access pattern (e.g., channel access pattern with (extremely) low latency), according to one embodiment. In Figure 11, the abscissa represents time.

[0226] As can be seen in Fig. 11, one or more resource elements 192 of the second channel access pattern can be arranged between the resource elements 112 of the first channel access pattern, wherein a reference point of a respective resource element of the second channel access pattern has a fixed time interval from a reference point of a respective resource element of the first channel access pattern.

[0227] In embodiments, a sub-data packet 113 with normal latency can be transmitted in each of the resource elements 112 of the first channel access pattern. The sub-data packet 113 with normal latency can also be referred to, for example, as a Class B sub-data packet (Class B Radio Burst). In embodiments, a sub-data packet 193 with (extremely) low latency can be transmitted in each of the resource elements 192 of the second channel access pattern 192. If a sub-data packet 193 with (extremely) low latency is transmitted per resource element 192, this sub-data packet can also be referred to, for example, as a Class C sub-data packet with low energy requirements (Class C ULP (ULP = ultra low power) Radio Burst).A reference point of a resource element 192 of the second channel access pattern, in which only one sub-data packet 193 with (extremely) low latency is transmitted, can, for example, have a fixed time interval of 136 symbol durations or 57.1 ms from a reference point of an immediately preceding resource element 112 of the first channel access pattern. In other words, a reference point of a sub-data packet 193 with (extremely) low latency can, for example, have a fixed time interval of 136 symbol durations or 57.1 ms from a reference point of an immediately preceding sub-data packet 113 with normal latency. Of course, the fixed time interval can also have a different value, such as 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, or 160 symbol durations. The reference points can, for example, be located in the middle of the resource elements or sub-data packets.

[0228] Alternatively or additionally, a plurality of sub-data packets 193 with (extremely) low latency can also be transmitted in the resource elements 192 of the second channel access pattern, such as two, three, or four sub-data packets with (extremely) low latency. In this case, a resource element 192 of the second channel access pattern can comprise a plurality of time slots, with one of the sub-data packets 193 with (extremely) low latency being transmitted per time slot. If a plurality of sub-data packets 193 with (extremely) low latency are transmitted per resource element 192, these sub-data packets can also be referred to, for example, as Class C sub-data packets with a high data rate (Class C HDR (HDR = high data rate) radio burst).A reference point of a resource element 192 of the second channel access pattern, in which several sub-data packets are transmitted with (extremely) low latency, can, for example, have a fixed time interval of 78.75 symbol durations or 33.1 ms from a reference point of an immediately preceding resource element 112 of the first channel access pattern. In other words, a reference point of a first sub-data packet 193 with (extremely) low latency of the several sub-data packets with (extremely) low latency can, for example, have a fixed time interval of 136 symbol durations or 57.1 ms from a reference point of an immediately preceding sub-data packet 113 with normal latency. Of course, the fixed time interval can also have a different value, such as 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, or 160 symbol durations.The reference points can be located, for example, in the middle of the resource element 112 of the first channel access pattern and in the middle of a first slot (in which a first sub-data packet with (extremely) low latency) of the resource element 192 of the second channel access pattern or in the middle of the sub-data packet 113 with normal latency and in the middle of a first sub-data packet 193 with (extremely) low latency of the plurality of sub-data packets with (extremely) low latency.

[0229] In other words, Fig. 11 shows a schematic view of an exemplary linking of a system according to sections A and B (labeled in Fig. 11 as sub-data packet 113 with normal latency (Class B Radio Burst)) and the new low-latency (LL-RE) resource elements (labeled in Fig. 11 as sub-data packets 193 with (extremely) low latency (Class C ULP Radio Burst and Class C HDR Radio Burst)). As can be seen in Fig. 11, the temporal distance depends only on the previous sub-data packet (or radio burst) (or resource element) from sections A and B and has a fixed distance of 136 and 78.75 symbol durations, respectively.

[0230] In Fig. 11, there are two different distances to the previous resource element after sections A and B, since for the new low latency (LL-RE) resource elements, different data rates (e.g., a first data rate called ULP (ULP = ultra low power, i.e., a data rate that results in low energy consumption) and a second data rate called HDR (HDR = high data rate, i.e., a data rate that is higher than the ULP data rate) are possible, which can also be used in parallel.

[0231] In embodiments, the distance to the previous sub-data packet (or radio burst) from sections A and B is fixed at 136 and 78.75 symbol durations, respectively (reference to the ULP data rate).

[0232] Similar to time slots, the frequency of the previous resource element from sections A and B can also be used for the new low-latency (LL-RE) resource elements. It is possible to use the same frequency directly or to specify a frequency offset. If the same bandwidth is to be used, those frequencies must be cyclically shifted back into the usable range in the case of a frequency offset.

[0233] In embodiments, the carrier frequency is the same or has a defined distance (or offset) to the previous sub-data packet (or radio burst) from sections A and B. If the same frequency or the same frequencies are used shifted by an offset and the bandwidth should be the same as sections A and B, this principle only works if the data rate or symbol rate is less than or equal to the data rate from section A. If the data rate is higher, this principle cannot be applied because the modulation bandwidth is larger at higher data rates or symbol rates and therefore more bandwidth is required.

[0234] Therefore, a different scheme for determining data rates must be used for higher data rates. One possibility, for example, would be to shift the frequencies at the band edges into the permissible range using a modulo operation, but this leads to uneven frequency utilization.

[0235] Since all participants must receive the system or mode according to sections A and B for time coordination, they also know the parameters for calculating the channel access pattern (e.g., times or time slots and frequency channels). At higher data rates for the low-latency resource elements (LL-RE), the parameters for calculating the channel access pattern according to sections A and B can be used to define a second mapping rule that is used only for the low-latency resource elements (LL-RE) at higher data rates. This rule can be designed to achieve equal utilization across all frequencies.

[0236] In embodiments, a new mapping rule can be used at higher data rates, which works with the parameters for calculating the channel access pattern according to sections A and B. Thus, no additional transmission of parameters for calculating the frequencies at higher data rates is necessary.

[0237] If the telegram splitting method is also to be used for ultra-low-latency mode, several of the low-latency transmission time slots 192 (LL-REs) shown in Fig. 10 can be used for a message. For example, using five transmission time slots 192 for the (extremely) low-latency sub-data packets would result in a latency of approximately 500 ms if the average spacing of the resource grid is 100 ms.

[0238] Fig. 12 shows a schematic view of the structure of a sub-data packet 193 with (extremely) low latency. As can be seen in Fig. 12, the sub-data packet 193 comprises two synchronization sequences 194 with a length of 16 symbols, with a data block with a length of 36 symbols arranged between the two synchronization sequences 194. Optionally, data blocks with up to 36 symbols each can be present before and after the synchronization sequences 194. The sub-data packet 193 can thus comprise a maximum of 140 symbols, 32 of which are pilot sequences.

[0239] In other words, Fig. 12 shows a possible structure of a sub-data packet 193 with (extremely) low latency. If five such sub-data packets were to comprise the entire data packet, up to 540 data symbols could be transmitted. At a code rate as in [1], this corresponds to just under 22 bytes of payload data. If length information and a CRC (cyclic redundancy check) for error detection are also used, just under 20 bytes of payload data remain. The synchronization sequence can be derived from known information, similar to [1]; this procedure is described in more detail in Section C.4. Alternatively, a fixed synchronization sequence can also be defined.

[0240] If more than the aforementioned 20 bytes are to be transmitted, the telegram can be combined into several blocks of, for example, five sub-data packets 193 each, similar to what is done in [1] for the downlink, but there in blocks of 18 sub-data packets each. The scheme of a block can be structured, for example, as shown in Fig. 13.

[0241] In detail, Fig. 13 shows a schematic diagram of the occupancy of a communication channel during a transmission of five sub-data packets 193 with (extremely) low latency. The ordinate represents the frequency and the abscissa represents time.

[0242] In embodiments, the sub-data packets 193 with (extremely) low latency (or of the first mode) can comprise more symbols than the sub-data packets with normal latency (or of the second mode). This results in a longer transmission time for the sub-data packets 193 with (extremely) low latency than for the sub-data packets with normal latency. If the pause between the sub-data packets with normal latency is insufficient for this, the data rate of the sub-data packets with (extremely) low latency can be selected accordingly higher.

[0243] In embodiments, multiple time slots with extremely low latency can be used together for a data packet consisting of multiple sub-data packets with (extremely) low latency. A new sub-data packet can be transmitted in each time slot. In embodiments, the data rate of the sub-data packets with (extremely) low latency can be different from the data rate of the sub-data packets with normal latency.

[0244] Figure 11 shows that at the HDR data rate, up to four sub-data packets (or radio bursts) can be transmitted in one resource element (RE). This can be used either for four parallel transmissions to different subscribers or for the embodiment described in Section C.2 with fewer subscribers.

[0245] In embodiments, multiple sub-data packets (or radio bursts) may be transmitted at the HDR data rate within a resource element (RE) (the second channel access pattern).

[0246] C.2 Interconnected repetition of subdata packets and early decoding

[0247] By introducing the telegram splitting method with sub-data packets with (extremely) low latency in Section C.1, the interference immunity of the transmission is increased at the expense of the transmission latency. However, if an error protection code with high redundancy is inserted as in [1] (in [1] the code rate is 1 / 3), early decoding of the sub-data packets after receiving a (true) subset of the sub-data packets is possible with sufficient SNR (signal-to-noise ratio) and no interference. This so-called early decoding thus makes it possible to reduce latency if the SNR is sufficiently good and the received sub-data packets do not contain too much interference.

[0248] In Section C.1, a maximum of one sub-data packet was transmitted in each possible time slot. Assuming the five sub-data packets from Section C.1, a code rate of 1 / 3 as in [1], and an interleaver that distributes the information evenly across all sub-data packets, early decoding would be possible after just two sub-data packets have been received. According to Section C.1, the latency could thus be reduced from five time slots to two time slots, assuming that the SNR is sufficient and interference is not too significant.

[0249] By varying the data rate as described in Section C.1, a shorter transmission time is achieved despite a higher number of symbols per sub-data packet. This also provides the option of repeating the sub-data packets in the time slots, i.e., transmitting more than one sub-data packet per time slot. See Fig. 11 for an example, where up to four sub-data packets (corresponding to the time slots) are transmitted in one resource element.

[0250] It is advisable not to repeat the same sub-data packet in a time slot, but rather a different one. A sensible nesting of the sub-data packets based on five sub-data packets per block is shown in Table 1.

[0251] Table 1 : Advantageous combination of repeated sub-data packets with five sub-data packets per block

[0252] The nested repetition of the sub-data packets, using the code rate from [1] and five sub-data packets, makes it possible to attempt early decoding after receiving only one time slot.

[0253] This allows the latency from Section C.1 to be reduced to one time slot. If the SNR is insufficient or interference is occupying the channel, further decoding can be performed after, for example, two time slots, etc. In cases where the SNR is at the limit of decoding capability, decoding will only be successful after all sub-data packets have been received, utilizing full redundancy.

[0254] By dividing a block into, for example, five sub-data packets and optionally complementary repeated transmission within a time slot, a latency similar to that in a system that does not split data packets can be achieved under good reception conditions, despite the telegram splitting procedure.

[0255] In some embodiments, one or optionally several sub-data packets from the same receiver can be transmitted in each time slot. Depending on the code rate and the number of sub-data packets per block, the receiver can perform early decoding after only two sub-data packets have been received. If decoding is successful, reception of this data packet can be completed; otherwise, the receiver waits for further sub-data packets.

[0256] Example: A transmission requires five sub-packets to be sent in five time slots. If time slots ABCDEF are available, then transmission can begin in any of the elements, not just at the beginning of a specific time slot.

[0257] The receiver checks all combinations to see if a transmission has taken place.

[0258] Here: ABCDE and BCDEF.

[0259] This includes all possible combinations, even beyond the limits of the system in Section A.

[0260] Example:

[0261] AO BO CO DO EO FO A1 B1 C1 D1 E1 F1 ...

[0262] For example, a transmission can start in EO, it then occupies EO and FO of the first block and A1, B1 and C2 of the second block.

[0263] The receiver checks all combinations again.

[0264] A0B0C0D0E0,

[0265] B0C0D0E0F0,

[0266] C0D0E0F0A1 , ....

[0267] C.3 Latency vs. Computational Effort / Power Consumption

[0268] In the previous sections C.1 and C.2, the goal was to reduce latency to a minimum in order to meet corresponding use cases with very high latency requirements. With the implementation described in Section C.2, a latency of less than 100 ms is even possible, depending on the spacing of the resource elements in Section A. However, this comes at the expense of power consumption, as mentioned above.

[0269] However, there are also applications that have a latency requirement of a few seconds (e.g. one to three seconds), which cannot be met by the system in sections A and B.

[0270] In (extremely) low latency mode, very low latency is possible if the beginning of a telegram is possible in every time slot. Nodes (or endpoints) with low hardware resources such as CPU / RAM / battery are not capable of running multiple detection and / or decoding operations in parallel. These nodes only search for telegrams beginning in every xth time slot. In the previous examples, parallel decoding is no longer necessary starting every fifth time slot. This is communicated accordingly when the node registers with the base station.

[0271] In embodiments, certain nodes with low hardware resources and / or nodes with moderate latency requirements may start a new message only every xth time slot. This is communicated to the base station when the node registers.

[0272] For example, a low-latency system (LL-RE system) with 18 sub-packets per block and the data rate as in [1] is assumed. Thus, if transmission can begin at any time slot, 18 detections would have to be initiated after each reception of a new time slot (RE), and in the worst case, up to 18 decoding operations would have to be initiated. If the start can only occur in every 18th resource element (time slot), only one detection and, if necessary, one decoding operation needs to be performed every 18 resource elements.

[0273] If a participant can also be addressed via the system from sections A and B, they may also have to perform detections and decoding there. If a detection from sections A and B happens to be in the same time slot, according to Section C.1, only a very short symbol duration remains until the detection of the low-latency resource elements (LL-RE) must begin.

[0274] This time requirement for computing power cannot typically be met in the receiver. To circumvent this, in exemplary embodiments, the times at which a message can begin can be linked to the times from sections A and B, and an offset can be added for the shift.

[0275] If the system consisting of sections A and B has a block size of, for example, 36 resource elements (RE), detection typically occurs every 36 resource elements (RE). If the low-latency system shown here (LL-RE system) has a block size of 18 resource elements (RE), the start of a new block can be at index 9 or 27, respectively, to improve or even maximize the distance from the system consisting of sections A and B.

[0276] In embodiments, a new message can only begin in every x-th time slot, whereby this time slot depends on the system of sections A and B. This time slot (RE) can be selected such that the time interval between the detection processes of the different modes is as large as possible.

[0277] C.4 Addressing via subscriber-specific preamble & indirect addressing via key

[0278] [1] describes a method in which the CMAC (one-key message authentication code) from the uplink is inserted into the downlink as an authenticating part of the synchronization sequence. This allows an uplink message to be directly confirmed without additional data, since only the sender and the receiver (or a group of receivers) know this CMAC.

[0279] Since there is no allocation of resources to specific nodes in (extremely) low-latency mode, as is the case with beacons in Section A, each participant must calculate a new synchronization for each possible time slot and, if necessary, evaluate a decoding, even if the message is intended for a different node. This leads to high power consumption the larger the network becomes, i.e., the more nodes use the (extremely) low-latency mode.

[0280] In exemplary embodiments, this problem can be circumvented by using part or all of the subscriber's address or a key derived from the address (e.g., a hash) as the pilot sequence. This information is unique for each node, allowing other nodes to abort reception during synchronization. To ensure that this method also works at low SNR, the subscriber's address can be protected with the same FEC (forward error correction) as the data to be transmitted, so that the error probability of the address is no worse than that of the data.

[0281] In embodiments, in contrast to the concept from [1] with authenticated receipt confirmation, the address may not only be known to the sender and the receiver or a group of receivers, but the address may be encrypted in the same way as the following payload data so that no conclusions can be drawn.

[0282] In some embodiments, part or all of the subscriber's address, or a code derived from the address (e.g., a hash), can be used as the pilot sequence. The address can be encrypted and / or a code can be inserted over the address for error protection. If only part of the address or no address at all is included in the pilot sequence, the remaining part of the address can be transmitted in the payload so that the nodes can be sure that the message is intended for them.

[0283] If the data is encrypted, a part or the entire address can be transmitted implicitly without any further data using the encryption, similar to [3].

[0284] In combination with the inclusion of part of the address in the pilot sequence, both methods make it possible to completely dispense with the additional transmission of the subscriber's address.

[0285] In embodiments, part or all of the subscriber's address is not transmitted and is given implicitly by the encryption.

[0286] 5. Encryption counter is derived from another mode or system

[0287] As described in [1], in addition to the key, a counter or similar can be used to encrypt data, which changes at certain intervals, for example to prevent replay attacks. The counter used for encryption must be known to both the sender and the receiver before the encrypted data is evaluated. In [1], the counter is transmitted unencrypted along with the data in the uplink. The same counter as in the previous uplink is used in the downlink. In Section B, the existing beacon counter is used for this purpose. This is known to the base station and all subscribers, as it is needed to calculate the channel access pattern. In Section 2, no further information needs to be transmitted via a counter.

[0288] For the (extremely) low latency system or (extremely) low latency mode proposed here, a counter is also required for encryption. Since, as described in Section C.1, the times of the low-latency resource elements (LL-RE) are made dependent on the times of the channel access pattern according to Section A, a subscriber who wishes to use the (extremely) low latency system must also be registered in the system according to Section A. This means that the subscriber also knows the beacon counter or another counter from the system according to Section A. This can therefore also be used for encryption. To ensure independence with regard to reuse of the counter between the two systems, further encryption initialization information is selected differently, for example by setting an extra bit for the low-latency mode.

[0289] In some embodiments, a counter from another system or mode can be used for encryption. This avoids the additional transmission of a counter, thus reducing overhead.

[0290] As mentioned in the introduction, the time interval between two beacons can range from 30 seconds to 5 minutes. This means that the beacon counter also only changes within this interval. If more than one message is to be sent to the same participant within this interval, the same counter can be used for all messages within this interval. This would allow the attacker to be vulnerable to replay attacks or known-plaintext attacks within the interval between two beacons.

[0291] This can be circumvented by introducing and transmitting an additional small counter, which is reset at the beginning of each new beacon. The maximum size of the counter is the maximum number of messages expected in the time span between two beacons. While this additional counter increases the amount of information to be transmitted, the bit depth of the additional counter is lower than if the beacon counter were not used at all.

[0292] In embodiments, in addition to the counter of the other system, another counter can be used, which is reset after each beacon.

[0293] Often, only a single message is transmitted to a participant during the time between two beacons, and only very rarely multiple messages. However, the additional counter must be included in each message for the encryption to work correctly, which in most cases results in unnecessary overhead due to the single message.

[0294] Alternatively, the counter can be transmitted to a subscriber only starting with the second message during the time period between two beacons. The subscriber knows that the first message is transmitted without the additional counter and that subsequent messages contain the counter.

[0295] In embodiments, the additional counter can only be transmitted from the second message to a subscriber during the time period between two beacons.

[0296] To completely avoid transmitting an additional counter, it can also be implicitly derived from the transmission time within the range between two beacons. The receiver thus knows that, for example, upon receiving a transmission at the first possible position within a beacon period, the additional counter will have the value 0, at the second possible position the value 1, and so on. In section A, each resource element is assigned a resource element counter that runs from 0 to N_RE_beaconPeriod (i.e., the number of resource elements within a beacon period) and restarts at zero at the next beacon period. This resource element counter is therefore ideally suited as a transmission position.

[0297] In embodiments, the additional counter can be derived implicitly from the transmission position within the beacon period and thus does not need to be transmitted.

[0298] C.6 Order of subpackages is derived from the grid

[0299] New messages can arrive at the base station at any time, which then need to be transmitted promptly. For (extremely) low-latency mode, it is essential that the transmission starts in the next available resource element or time slot, if possible. This causes several problems at the receiver, depending on the pilot sequences used:

[0300] • If the pilot sequence is unique for each sub-packet, the receiver must be able to detect all possible pilot sequences. These parallel detectors result in a significantly increased computational load and increase the overall probability of false detections, as the false detections of the individual detectors accumulate.

[0301] • If the pilot sequences within a telegram are identical, the assignment of the received sub-data packets to a sub-packet index is ambiguous in the event of a packet loss at the beginning or end of a telegram. In both cases, the receiver receives a contiguous number of sub-data packets that is lower than the total expected number of sub-data packets, without an absolute reference. • If this pilot sequence is also identical for all telegrams, this problem is exacerbated. With a seamless transmission of multiple telegrams in the same slot, the receiver does not know which sub-data packets belong to a transmission. Therefore, all possible combinations must be tried, which increases the computational load.

[0302] In embodiments, these problems can be reduced by a sub-data packet assignment derived from the grid. This assignment is performed individually for the four HDR time slots, which are shown in Fig. 11 as an example for a resource element. Fig. 14 shows a possible assignment of the sub-data packets according to their indices using the resource element index and the time slot index (slot). With this assignment, sub-data packets with the index RE%5 are transmitted in time slot 0, sub-data packets with the index (RE+3)%5 (where % corresponds to the modulo operator) in time slot 1, sub-data packets with the index (RE+2)%5 in time slot 2, and sub-data packets with the index (RE+1)%5 in time slot 3. This time slot-dependent assignment enables the repetition of the sub-data packets from Section C.2. As a result, the sub-data packets are usually not received in strictly ascending order.

[0303] In detail, Fig. 14 shows a schematic diagram of the assignment of sub-data packets according to their indices based on the selected time slot for the first eight resource elements of the second channel access pattern. In Fig. 14, the ordinate represents the time slot indices, and the abscissa represents the resource element indices.

[0304] The structure shown in Fig. 14 with four transmission time slots per resource element makes it possible, for example, to transmit the initial transmission in time slot 0 or time slot 1 and to repeat it in each (e.g. following) free time slot in the same resource element, e.g. since the same sub-data packets are never transmitted there.

[0305] For example, the following table applies to a possible advantageous arrangement for repeated transmissions:

[0306] Example: Assume that a transmission begins at the time of the resource element with index 1, does not use repetition, uses the time slot with index 0, and comprises 5 sub-data packets. According to Fig. 14, the sub-data packet with index 1 is transmitted first, followed by the sub-data packet with index 2, then the sub-data packet with index 3, then the sub-data packet with index 4, and finally the sub-data packet with index 0.

[0307] If a (further) transmission begins at the resource element with index 0 and uses the time slot with index 1 (e.g., because another transmission is already taking place in the time slot with index 0), the sub-data packets are transmitted in the following order: (3, 4, 0, 1, 2). If additional repetitions are sent in the first two resource elements in the time slot with index 3 according to Section C.2, these would be the sub-data packets with indices 2 and 3.

[0308] With this assignment, it is clear to the receiver which of the five sub-data packets was received, which allows for easy restoration of the original symbol sequence (deinterleaving):

[0309] • If a separate pilot sequence is used for each sub-data packet, this fixed assignment allows the respective sub-data packet index to be known in advance. This means that only one detection needs to be calculated per time slot, which benefits computing power and the probability of false detection.

[0310] • If a shared pilot sequence is used within a telegram, an unreceived sub-data packet at the beginning or end of the telegram has only a limited effect. These packet losses have no influence on the sub-data packet assignment and thus the reconstructed symbol sequence.

[0311] • If only a single pilot sequence is used for all sub-data packets of all telegrams, the start and end of the individual telegrams cannot be clearly determined. However, if a decoding attempt is initiated for consecutive sub-data packets, their packet assignment is unambiguous, which reduces the number of possibilities to be tested.

[0312] In embodiments, the counter of the time slots (REs, or resource element indexes) and the position within the time slots (slot) can determine which sub-data packet is sent.

[0313] D. Further implementation examples

[0314] Embodiments find application in systems for the wireless transmission of data from end devices to a base station or from one or more base stations to end devices. For example, a system may be a personal area network (PAN) or a low-power wide area network (LPWAN), where the end devices may be, for example, battery-operated sensors (sensor nodes).

[0315] Embodiments are aimed at application cases in which a message (data packet) is transmitted in a radio network in several partial data packets (so-called telegram splitting method, English: Telegram Splitting [x]) and in which several mutually uncoordinated radio networks access common radio resources (e.g. common frequency band).

[0316] As already mentioned, the embodiments described herein can be used to transmit data between the subscribers of the communication system based on the telegram splitting method. In the telegram splitting method, data, such as a telegram or data packet, is divided into a plurality of sub-data packets (or partial data packets, or sub-packets) and the sub-data packets are transmitted from one subscriber to another subscriber (e.g. from the base station to the end point, or from the end point to the base station) of the communication system using a time and / or frequency hopping pattern, wherein the subscriber who receives the sub-data packets reassembles (or combines) them to obtain the data packet. Each of the sub-data packets contains only a part of the data packet.The data packet may also be channel-coded, so that only a portion of the sub-data packets is required to decode the data packet error-free.

[0317] When transmitting data based on the telegram splitting method, the sub-data packets can be transmitted distributed among a subset (e.g., a selection) of the available resources of the network-specific channel access pattern. Specifically, the sub-data packets can be transmitted based on the relative channel access pattern, i.e., within the resources of the relative channel access pattern. For example, one sub-data packet can be transmitted per resource.

[0318] Although some aspects have been described in the context of a device, it should be understood that these aspects also represent a description of the corresponding method, so that a block or component of a device can also be understood as a corresponding method step or as a feature of a method step. Analogously, aspects described in the context of or as a method step also represent a description of a corresponding block, detail, or feature of a corresponding device. Some or all of the method steps may be performed by (or using) a hardware apparatus, such as a microprocessor, a programmable computer, or an electronic circuit. In some embodiments, some or more of the key method steps may be performed by such an apparatus.

[0319] Depending on specific implementation requirements, embodiments of the invention may be implemented in hardware or software. The implementation may be performed using a digital storage medium, such as a floppy disk, a DVD, a Blu-ray Disc, a CD, a ROM, a PROM, an EPROM, an EEPROM, or a FLASH memory, a hard disk, or other magnetic or optical storage device storing electronically readable control signals that can interact or cooperate with a programmable computer system to perform the respective method. Therefore, the digital storage medium may be computer-readable.

[0320] Some embodiments according to the invention thus comprise a data carrier having electronically readable control signals capable of interacting with a programmable computer system such that one of the methods described herein is carried out.

[0321] In general, embodiments of the present invention may be implemented as a computer program product having a program code, wherein the program code is effective to perform one of the methods when the computer program product is run on a computer.

[0322] The program code can, for example, also be stored on a machine-readable medium.

[0323] Other embodiments include the computer program for performing one of the methods described herein, wherein the computer program is stored on a machine-readable carrier.

[0324] In other words, an embodiment of the method according to the invention is thus a computer program which has a program code for carrying out one of the methods described herein when the computer program runs on a computer.

[0325] A further embodiment of the method according to the invention is thus a data carrier (or a digital storage medium or a computer-readable medium) on which the computer program for performing one of the methods described herein is recorded. The data carrier, the digital storage medium, or the computer-readable medium is typically physical and / or non-perishable or non-transient.

[0326] A further embodiment of the method according to the invention is thus a data stream or a sequence of signals that represents the computer program for carrying out one of the methods described herein. The data stream or the sequence of signals can be configured, for example, to be transferred via a data communication connection, for example, via the Internet.

[0327] A further embodiment comprises a processing device, for example a computer or a programmable logic device, which is configured or adapted to carry out one of the methods described herein.

[0328] A further embodiment comprises a computer on which the computer program for performing one of the methods described herein is installed.

[0329] A further embodiment according to the invention comprises a device or system designed to transmit a computer program for performing at least one of the methods described herein to a recipient. The transmission can be electronic or optical, for example. The recipient can be, for example, a computer, a mobile device, a storage device, or a similar device. The device or system can, for example, comprise a file server for transmitting the computer program to the recipient.

[0330] In some embodiments, a programmable logic device (e.g., a field-programmable gate array, an FPGA) may be used to perform some or all of the functionalities of the methods described herein. In some embodiments, a field-programmable gate array may cooperate with a microprocessor to perform any of the methods described herein. In general, in some embodiments, the methods are performed by any hardware device. This may be general-purpose hardware such as a computer processor (CPU) or method-specific hardware such as an ASIC.

[0331] The devices described herein may be implemented, for example, using a hardware apparatus, or using a computer, or using a combination of a hardware apparatus and a computer.

[0332] The devices described herein, or any components of the devices described herein, may be implemented at least partially in hardware and / or in software (computer program).

[0333] The methods described herein may be implemented, for example, using a hardware apparatus, or using a computer, or using a combination of a hardware apparatus and a computer.

[0334] The methods described herein, or any components of the methods described herein, may be implemented at least partially by hardware and / or by software.

[0335] The above-described embodiments are merely illustrative of the principles of the present invention. It is understood that modifications and variations of the arrangements and details described herein will be apparent to others skilled in the art. Therefore, it is intended that the invention be limited only by the scope of the following claims and not by the specific details presented in the description and explanation of the embodiments herein.

[0336] Bibliography

[0001] ETSI TS 103 357 V1.1.1 (2018-06) - “Short Range Devices; Low Throughput

[0337] Networks (LTN); Protocols for radio interface A.”

[0338] [2] DE 10 2018210245 A1 [3] DE 10 2017204 181 A1

[0339] [4] DE 10 2011 082 098 B4

[0340] List of abbreviations

[0341] CRC: Cyclic Redundancy Check

[0342] LPWAN: Low Power Wide Area Network

[0343] LSB: Least Significant Bit(s)

[0344] MSB: Most Significant Bit(s) PAN: Personal Area Network

[0345] TLS: Transport Layer Security

[0346] TSMA: Telegram-Splitting-Multiple-Access

Claims

Patent claims 1. An endpoint (106_1) of a wireless communication system, wherein the endpoint (106_1) is configured to operate in a first mode and a second mode, wherein the endpoint (106_1) is configured to receive a signal (120), wherein the signal (120) comprises information about a first channel access pattern for the first mode, wherein the endpoint (106_1) is configured to determine the first channel access pattern for the first mode based on the information about the first channel access pattern, wherein the endpoint (106_1) is configured to determine a second channel access pattern for the second mode based on the information about the first channel access pattern, wherein the endpoint (106_1) is configured to transmit and / or receive data in the second mode using the second channel access pattern, wherein the first channel access pattern for the first mode enables data transmission with a first latency,wherein the second channel access pattern for the second mode enables data transmission with a second latency, the second latency being lower than the first latency., 2. The endpoint (106_1) of claim 1, wherein the endpoint (106_1) is configured to determine the second channel access pattern based solely on the information about the first channel access pattern.

3. Endpoint (106_1) according to one of claims 1 to 2, wherein the endpoint (106_1) is configured to determine the first channel access pattern from the information of the signal (120) via a first mapping rule, wherein the endpoint (106_1) is configured to determine the second channel access pattern from the information of the signal (120) via a second mapping rule.

4. Endpoint (106_1) according to one of claims 1 to 3, wherein the information about the first channel access pattern describes a state of a number sequence generator for generating a number sequence or wherein the information about the first channel access pattern describes a number of a number sequence, the number sequence determining the first channel access pattern.

5. The endpoint (106_1) of any one of claims 1 to 4, wherein the endpoint (106_1) is configured to transmit and / or receive data in the first mode using the first channel access pattern.

6. Endpoint (106_1) according to one of claims 1 to 5, wherein the first channel access pattern indicates a frequency- and / or time-hopping-based occupancy of resource elements (112) usable for the communication of the communication system, and / or wherein the second channel access pattern indicates a frequency- and / or time-hopping-based occupancy of resource elements (192) usable for the communication of the communication system.

7. The endpoint (106_1) of claim 6, wherein the endpoint (106_1) is configured to send and / or receive data in a subset of the occupancy of resource elements (112) specified by the first channel access pattern in the first mode, and / or wherein the endpoint (106_1) is configured to send and / or receive data in a subset of the occupancy of resource elements (192) specified by the second channel access pattern in the second mode.

8. Endpoint (106_1) according to one of claims 6 to 7, wherein time intervals between immediately successive resource elements (112) of the first channel access pattern are greater than time lengths of the resource elements (192) of the second channel access pattern.

9. Endpoint (106_1) according to one of claims 6 to 8, wherein in each case a resource element (192) of the second channel access pattern lies at a respective time interval between two immediately successive resource elements (112) of the first channel access pattern.

10. Endpoint (106_1) according to one of claims 6 to 9, wherein a reference point of a respective resource element (192) of the second channel access pattern has a fixed time interval from a reference point of a respective resource element (112) of the first channel access pattern.

11. Endpoint (106_1) according to one of claims 6 to 9, wherein the resource elements (112) of the first channel access pattern are defined in time relative to a periodic grid, wherein a reference point of a respective resource element (192) of the second channel access pattern has a fixedly defined time distance from a respective grid point of the periodic grid.

12. Endpoint (106_1) according to claim 10 or 11, wherein the fixed time interval is 136 symbol durations or 57.1 ms, or wherein the fixed time interval is 78.75 symbol durations or 33.1 ms.

13. Endpoint (106_1) according to one of claims 6 to 12, wherein a respective resource element (192) of the second channel access pattern is on the same frequency as a respective resource element (112) of the first channel access pattern, or wherein a respective resource element (192) of the second channel access pattern has a fixedly defined frequency spacing from a respective resource element (112) of the first channel access pattern.

14. Endpoint (106_1) according to one of claims 6 to 13, wherein the endpoint (106_1) is configured to send and / or receive data divided into a plurality of sub-data packets according to the second channel access pattern, wherein one or more sub-data packets of the plurality of sub-data packets are sent and / or received in a resource element (192) of the second channel access pattern.

15. The endpoint (106_1) of claim 14, wherein a respective sub-data packet of the plurality of sub-data packets within a respective resource element (192) of the second channel access pattern has a pseudorandom offset in time and / or frequency.

16. The endpoint (106_1) of any one of claims 6 to 15, wherein a data rate of the data transmitted in the second channel access pattern is higher than a data rate of the data transmitted in the first channel access pattern.

17. Endpoint (106_1) according to one of claims 14 to 15, wherein the sub-data packets are channel-coded, so that for successful decoding of the data in the case of error-free transmission or a sufficient signal-to- Noise ratio only a true subset of the majority of sub-data packets is required.

18. The endpoint (106_1) of claim 17, wherein the endpoint (106_1) is configured to receive and decode a true subset of the plurality of sub-data packets to obtain the data, wherein the endpoint (106_1) is configured not to receive any further sub-data packets of the plurality of sub-data packets if the decoding of the data based on the true subset of the plurality of data packets was successful.

19. Endpoint (106_1) according to one of claims 17 to 18, wherein in a resource element (192) of the second channel access pattern, a plurality of different sub-data packets of the plurality of sub-data packets are sent and / or received.

20. Endpoint (106_1) according to one of claims 17 to 19, wherein at least a true subset of the plurality of sub-data packets are repeatedly transmitted, wherein a resource element (192) of the second channel access pattern includes at least an initial transmission of a first sub-data packet and a retransmission of a second sub-data packet, wherein the first sub-data packet and the second sub-data packet are different.

21. Endpoint (106_1) according to one of claims 6 to 20, wherein the data comprises one or more sub-data packets, wherein a transmission of a data packet can only start in every x-th resource element (192) of the second channel access pattern, where x is a natural number greater than or equal to three.

22. Endpoint (106_1) according to claim 21, wherein the endpoint (106_1) is configured to derive the number x from the information about the first channel access pattern, or wherein the endpoint (106_1) is configured to receive the number x from a base station (104) of the communication system, or wherein the number x is fixed.

23. The endpoint (106_1) of any one of claims 1 to 22, wherein the data comprises a pilot sequence, the pilot sequence being derived from information identifying the endpoint (106_1), the endpoint (106_1) being configured to receive the data when the endpoint (106_1) is identified via the pilot sequence.

24. The endpoint (106_1) of claim 23, wherein the endpoint (106_1) is configured to abort reception of the data if the endpoint (106_1) is not identified via the pilot sequence.

25. The endpoint (106_1) according to any one of claims 1 to 24, wherein the information about the first channel access pattern describes a number of a number sequence, the number sequence determining the first channel access pattern, the data being encrypted by means of encryption, a counter used for the encryption being derived from the first channel access pattern or from the number of the number sequence.

26. Endpoint (106_1) according to claim 25, wherein the counter is a first counter, where a second counter is also used for encryption.

27. The endpoint (106_1) of claim 26, wherein the data comprises the second counter.

28. The endpoint (106_1) of claim 26, wherein the endpoint (106_1) is configured to receive a control signal, wherein the endpoint (106_1) is configured to modify the second counter in response to receiving the control signal.

29. Endpoint (106_1) according to one of claims 26 to 28, wherein the control signal is transmitted periodically, wherein the second counter is reset after each transmission of the control signal.

30. Endpoint (106_1) according to one of claims 6 to 29, wherein the endpoint (106_1) is configured to receive data divided into a plurality of sub-data packets according to the second channel access pattern, wherein the plurality of sub-data packets are transmitted in a plurality of consecutive resource elements (192) of the second channel access pattern, wherein an order in which the plurality of sub-data packets are transmitted depends on indices of the resource elements (192) of the second channel access pattern in which the plurality of sub-data packets are transmitted, or wherein an order in which the plurality of sub-data packets are transmitted depends on indices of the resource elements (112) of the first channel access pattern that immediately precede the respective resource elements (192) of the second channel access pattern in which the plurality of sub-data packets are transmitted.

31. The endpoint (106_1) of claim 30, wherein the order in which the plurality of sub-data packets are transmitted is further dependent on an index of a slot within the respective resource elements (192) of the plurality of consecutive resource elements (192) of the second channel access pattern in which the plurality of sub-data packets are transmitted.

32. Endpoint (106_1) according to one of claims 6 to 29, wherein the data comprises a data packet that is transmitted divided into five sub-data packets, wherein the plurality of sub-data packets are transmitted in five consecutive resource elements (192) of the second channel access pattern, wherein an order in which the five sub-data packets are transmitted depends on an index of a resource element (192) of the second channel access pattern or first channel access pattern that immediately precedes a respective resource element (192) of the second channel access pattern in which a transmission of the five sub-data packets begins, and an index of a slot within the respective resource elements (192) in which the five sub-data packets are transmitted, wherein the order in which the five sub-data packets are transmitted is based on the following table: where in the table each element describes an index of a respective sub-data packet.

33. A base station (104) of a wireless communication system, wherein the base station (104) is configured to operate in a first mode and in a second mode, wherein the base station (104) is configured to transmit a signal (120), wherein the signal (120) comprises information about a first channel access pattern for the first mode, wherein the base station (104) is configured to determine the first channel access pattern for the first mode based on the information about the first channel access pattern, wherein the base station (104) is configured to determine a second channel access pattern for the second mode based on the information about the first channel access pattern, wherein the base station (104) is configured to transmit and / or receive data in the second mode using the second channel access pattern, wherein the first channel access pattern for the first mode enables data transmission with a first latency,wherein the second channel access pattern for the second mode enables data transmission with a second latency, the second latency being lower than the first latency., 34. The base station (104) of claim 34, wherein the base station (104) is configured to determine the second channel access pattern based solely on the information about the first channel access pattern.

35. Base station (104) according to one of claims 33 to 34, wherein the base station (104) is configured to determine the first channel access pattern from the information of the signal (120) using a first mapping rule, wherein the base station (104) is configured to determine the second channel access pattern from the information of the signal (120) using a second mapping rule.

36. Base station (104) according to one of claims 33 to 35, wherein the information about the first channel access pattern describes a state of a number sequence generator for generating a number sequence or wherein the information about the first channel access pattern describes a number of a number sequence, the number sequence determining the first channel access pattern.

37. The base station (104) of any one of claims 33 to 36, wherein the base station (104) is configured to transmit and / or receive data in the first mode using the first channel access pattern.

38. Base station (104) according to one of claims 33 to 37, wherein the first channel access pattern indicates a frequency- and / or time-hopping-based occupancy of resource elements (112) usable for the communication of the communication system, and / or wherein the second channel access pattern indicates a frequency- and / or time-hopping-based occupancy of resource elements (192) usable for the communication of the communication system.

39. The base station (104) of claim 38, wherein the base station (104) is configured to transmit and / or receive data in a subset of the occupancy of resource elements (112) specified by the first channel access pattern in the first mode, and / or wherein the base station (104) is configured to transmit and / or receive data in a subset of the occupancy of resource elements (112) specified by the second channel access pattern in the second mode.

40. Base station (104) according to one of claims 38 to 39, wherein time intervals between immediately successive resource elements (112) of the first channel access pattern are greater than time lengths of the resource elements (192) of the second channel access pattern.

41. Base station (104) according to one of claims 38 to 40, wherein in each case one resource element (192) of the second channel access pattern is located at a respective time interval between two immediately successive resource elements (112) of the first channel access pattern.

42. Base station (104) according to one of claims 38 to 41, wherein a reference point of a respective resource element (192) of the second channel access pattern has a fixed time interval from a reference point of a respective resource element (112) of the first channel access pattern.

43. Base station (104) according to one of claims 38 to 42, wherein the resource elements (112) of the first channel access pattern are defined in time relative to a periodic grid, wherein a reference point of a respective resource element (192) of the second channel access pattern has a fixedly defined time distance from a respective grid point of the periodic grid.

44. Base station (104) according to claim 42 or 43, wherein the fixed time interval is 136 symbol durations or 57.1 ms, or wherein the fixed time interval is 78.75 symbol durations or 33.1 ms.

45. Base station (104) according to one of claims 38 to 44, wherein a respective resource element (192) of the second channel access pattern is on the same frequency as a respective resource element (112) of the first channel access pattern, or wherein a respective resource element (192) of the second channel access pattern has a fixedly defined frequency spacing from a respective resource element (112) of the first channel access pattern.

46. Base station (104) according to one of claims 38 to 45, wherein the base station (104) is configured to transmit and / or receive data divided into a plurality of sub-data packets according to the second channel access pattern, wherein one or more sub-data packets of the plurality of sub-data packets are transmitted and / or received in a resource element (192) of the second channel access pattern.

47. The base station (104) of claim 46, wherein a respective sub-data packet of the plurality of sub-data packets within a respective resource element (192) of the second channel access pattern has a pseudorandom offset in time and / or frequency.

48. The base station (104) of any one of claims 38 to 47, wherein a data rate of the data transmitted in the second channel access pattern is higher than a data rate of the data transmitted in the first channel access pattern.

49. Base station (104) according to one of claims 46 to 47, wherein the sub-data packets are channel-coded such that only a true subset of the plurality of sub-data packets is required for successful decoding of the data with error-free transmission or a sufficient signal-to-noise ratio.

50. The base station (104) of claim 49, wherein the base station (104) is configured to receive and decode a true subset of the plurality of sub-data packets to obtain the data, wherein the base station (104) is configured not to receive any further sub-data packets of the plurality of sub-data packets if the decoding of the data based on the true subset of the plurality of data packets was successful.

51. Base station (104) according to one of claims 49 to 50, wherein in a resource element (192) of the second channel access pattern, a plurality of different sub-data packets of the plurality of sub-data packets are transmitted and / or received.

52. Base station (104) according to one of claims 49 to 51, wherein at least a true subset of the plurality of sub-data packets are repeatedly transmitted, wherein a resource element (192) of the second channel access pattern contains at least an initial transmission of a first sub-data packet and a retransmission of a second sub-data packet, wherein the first sub-data packet and the second sub-data packet are different.

53. Base station (104) according to one of claims 38 to 52, wherein the data comprises one or more sub-data packets, wherein a transmission of a data packet can only begin in every x-th resource element (192) of the second channel access pattern, where x is a natural number greater than or equal to three.

54. Base station (104) according to claim 53, wherein the base station (104) is configured to derive the number x from the information about the first channel access pattern, or wherein the number x is fixed, or wherein the number x is predetermined by the endpoint (106_1).

55. The base station (104) of any one of claims 33 to 54, wherein the base station (104) is configured to transmit the data to an endpoint (106_1), the data comprising a pilot sequence, the base station (104) being configured to derive the pilot sequence from information identifying the endpoint (106_1).

56. The base station (104) according to any one of claims 33 to 55, wherein the information about the first channel access pattern describes a number of a number sequence, the number sequence determining the first channel access pattern, the base station (104) being configured to encrypt the data by means of encryption, a counter used for the encryption being derived from the first channel access pattern or from the number of the number sequence.

57. The base station (104) of claim 56, wherein the counter is a first counter, the base station (104) being configured to further use a second counter for encryption.

58. Base station (104) according to claim 57, wherein the base station (104) is configured to provide the data with the second counter.

59. The base station (104) of claim 57, wherein the base station (104) is configured to transmit a control signal, wherein the base station (104) is configured to modify the second counter in response to transmitting the control signal.

60. Base station (104) according to one of claims 57 to 59, wherein the control signal is transmitted periodically, the second counter being reset after each transmission of the control signal.

61. Base station (104) according to one of claims 38 to 60, wherein the base station (104) is configured to transmit data divided into a plurality of sub-data packets according to the second channel access pattern, wherein the plurality of sub-data packets are transmitted in a plurality of consecutive resource elements (192) of the second channel access pattern, wherein an order in which the plurality of sub-data packets are transmitted depends on indices of the resource elements (192) of the second channel access pattern in which the plurality of sub-data packets are transmitted, or wherein an order in which the plurality of sub-data packets are transmitted depends on indices of the resource elements (112) of the first channel access pattern that immediately precede the respective resource elements (192) of the second channel access pattern in which the plurality of sub-data packets are transmitted.

62. Base station (104) according to claim 61, wherein the order in which the plurality of sub-data packets are transmitted is further dependent on an index of a slot within the respective resource elements (192) of the plurality of consecutive resource elements (192) of the second channel access pattern in which the plurality of sub-data packets are transmitted.

63. Base station (104) according to one of claims 38 to 60, wherein the data comprises a data packet that is transmitted divided into five sub-data packets, wherein the plurality of sub-data packets are transmitted in five consecutive resource elements (192) of the second channel access pattern, wherein an order in which the five sub-data packets are transmitted depends on an index of a resource element (192) of the second channel access pattern or the first channel access pattern that immediately precedes a respective resource element (192) of the second channel access pattern in which a transmission of the five sub-data packets begins, and an index of a slot within the respective resource elements (192) in which the five sub-data packets are transmitted, wherein the order in which the five sub-data packets are transmitted is based on the following table: where in the table each element describes an index of a respective sub-data packet.

64. A method for operating an endpoint (106_1) of a communication system, the endpoint (106_1) being configured to operate in a first mode and a second mode, the method comprising: Receiving a signal (120), wherein the signal (120) comprises information about a first channel access pattern for the first mode, Determining the first channel access pattern for the first mode based on the information about the first channel access pattern, Determining the second channel access pattern for the second mode based on the information about the first channel access pattern, Transmitting and / or receiving data using the second channel access pattern, wherein the first channel access pattern for the first mode enables data transmission with a first latency, wherein the second channel access pattern for the second mode enables data transmission with a second latency, wherein the second latency is lower than the first latency.

65. A method of operating a base station of a communication system, the base station being configured to operate in a first mode and a second mode, the method comprising: Sending a signal (120), the signal (120) comprising information about a first channel access pattern for the first mode, Determining the first channel access pattern for the first mode based on the information about the first channel access pattern, Determining the second channel access pattern for the second mode based on the information about the first channel access pattern, Transmitting and / or receiving data using the second channel access pattern, wherein the first channel access pattern for the first mode enables data transmission with a first latency, wherein the second channel access pattern for the second mode enables data transmission with a second latency, wherein the second latency is lower than the first latency.

66. A computer program for carrying out the method according to claim 64 or 65, if the computer program runs on a computer, microprocessor or software-defined receiver.

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