Method for controlling data transmission in a radio communication system

Abstract

The invention relates to a method of operating a base transceiver station of a cellular radio communication system to control transmission of radio signals to a user equipment, the method comprising determining frequency hopping control information indicative of a frequency hopping set of frequency sub-bands of a downlink frequency band of a downlink channel of the cellular radio communication system to be used for a contiguous radio signal segment of transmission of radio signals to the user equipment, and indicative of a frequency hopping time order of the frequency sub-bands of the frequency hopping set to be used for the contiguous radio signal segment of transmission of radio signals to the user equipment; wherein determining the frequency hopping control information comprises determining user equipment frequency hopping restriction information indicative of one or more frequency sub-bands of the downlink frequency band to be excluded from the frequency hopping set, and using the user equipment frequency hopping restriction information for determining the frequency hopping set.

Description

Technical Field

[0001] The present invention relates to a method for operating a base station transceiver of a cellular radio communication system to control the base station transceiver to transmit radio signals to a user equipment, to a controller device for controlling the transmission of radio signals from a base station transceiver of a cellular radio communication system to a user equipment, to a base station transceiver for use in a cellular radio communication system, and to a method for operating a user equipment of a cellular radio communication system to control the user equipment to receive radio signals from the base station transceiver. Background Technology

[0002] In the field of wireless communication networks, frequency hopping schemes are frequently used to transmit radio signals from base transceivers to user equipment. When using frequency hopping to transmit radio signals, the frequency sub-bands of the downlink frequency band used for transmission are frequently changed according to a frequency hopping scheme known to both the base transceiver and the user equipment, in order to reduce the impact of interference sources on transmission. Different frequency hopping schemes are known in the prior art. Performing frequency hopping based on a pre-known sequence has the advantage of avoiding transient signaling during the execution of the frequency hopping sequence.

[0003] WO 2018 / 073812 A1 describes a method in a wireless communication network, including determining a frequency hopping sequence for communication between a wireless device and a network node. The frequency hopping sequence used is a function of a first frequency hopping sequence and a second frequency hopping sequence. The first frequency hopping sequence has a first frequency step size and a first sequence length, and the second frequency hopping sequence has a second frequency step size and a second sequence length. The first frequency step size is greater than the second frequency step size. Furthermore, the method in WO 2018 / 073812A1 includes communicating on a frequency selected according to the determined frequency hopping sequence. Summary of the Invention

[0004] The objective of this invention is to provide an improved frequency hopping scheme.

[0005] According to a first aspect of the invention, the objective of providing an improved frequency hopping scheme is achieved by operating a base station transceiver. In the second and third aspects, the invention comprises a controller device for a base station transceiver and a base station transceiver. In the fourth aspect, the invention comprises a method for operating user equipment.

[0006] In the fifth and sixth aspects, the present invention comprises a computer program for controlling a base station transceiver and a computer program for controlling a user equipment.

[0007] The method according to the first aspect of the present invention will now be described.

[0008] The method according to a first aspect of the invention relates to operating a base station transceiver of a cellular radio communication system to control the transmission of radio signals to user equipment.

[0009] The method includes determining frequency hopping control information. The frequency hopping control information indicates a set of frequency subbands of a downlink channel in a cellular radio communication system for transmitting radio signals to a user equipment in a continuous radio signal segment. Furthermore, the frequency hopping control information indicates the hopping time sequence of the frequency subbands of the set of frequency hopping signals in the continuous radio signal segment for transmitting radio signals to the user equipment.

[0010] According to the method in the first aspect, the frequency hopping control information is determined to include - Determine user equipment frequency hopping restriction information, which indicates one or more frequency sub-bands of the downlink frequency band to be excluded from the frequency hopping set, and - The frequency hopping set is determined using the user equipment frequency hopping restriction information.

[0011] This invention is based on the understanding that frequency hopping schemes are highly effective in reducing the impact of interference sources on transmission. Certain environments in which base station transceivers and user equipment operate contain interference sources that affect transmission on one or more frequencies. To reduce the impact of interference sources on transmission, frequency hopping schemes are used, in which multiple frequency sub-bands of the downlink frequency band of the downlink channel of a cellular radio communication system transmit consecutive radio signal segments according to the frequency hopping time sequence.

[0012] Furthermore, the present invention includes the understanding that the positive effects described for a given frequency hopping scheme can be improved by taking into account any limitations as a set of appropriate frequency subbands that are individual constraints for a given user equipment.

[0013] Based on this understanding, the method of the present invention further includes determining user equipment frequency hopping restriction information, which indicates one or more frequency sub-bands of downlink frequency bands to be excluded from the frequency hopping set, and using the user equipment frequency hopping restriction information to determine the frequency hopping set.

[0014] For example, in addition to the environmental interference sources mentioned above, reception performance can also be affected by internal interference sources within the user equipment, also known as self-interference. Especially due to the miniaturization of devices, wireless receiver modules are now very close to other modules within the compact housing of user equipment. For example, DC-DC converters (especially switch-mode converters) or memory modules can become internal interference sources. The user equipment manufacturer is generally aware of such effects in the operation of a given user equipment. This invention makes such information available to the base transceiver to control the frequency hopping scheme to be used in communication with a given user equipment. Therefore, in this example of self-interference, the impact of internal self-interference sources can be reduced by using user equipment frequency hopping limitation information to exclude those frequencies from the frequency hopping set that exhibit reception performance degradation due to such self-interference. However, it should be noted that the given example does not limit any limitations known to apply to a given user equipment when determining the frequency hopping control information at the current location of the user equipment, as can be provided as user equipment frequency hopping limitation information.

[0015] Preferred embodiments of the method will now be described.

[0016] In different embodiments, the base station transceiver determines the user equipment frequency hopping restriction information from different sources. In a preferred embodiment of the method of operating the base station transceiver, determining the user equipment frequency hopping restriction information includes receiving the user equipment frequency hopping restriction information from the user equipment. A particular advantage of this embodiment is that the individual user equipment frequency hopping restriction information is maintained directly on the device to which it applies and is obtained directly from the device to which it applies. This avoids intra-network control communications for maintaining and determining this information. Therefore, fewer computational and / or storage resources are required in the network.

[0017] In another preferred embodiment of the method, determining the user equipment frequency hopping restriction information includes signaling to the user equipment minimum reception performance information for one or more frequency subbands, wherein the minimum reception performance information indicates the maximum received bit error rate at the user equipment, or similarly indicates any amount of signal quality information (RSSI, BER, etc.) at the receiver side. This allows characteristics of the base station transceiver used to transmit radio signals, such as the maximum coverage enhancement level, to be taken into account when determining the user equipment frequency hopping restriction information. Therefore, this can be useful in variations of this embodiment because the frequency hopping restriction information received from the user equipment takes into account the minimum reception performance information: in other words, the frequency hopping restriction information received from the user equipment depends on the minimum reception performance information. For example, if the user equipment cannot meet a specific level of the required bit error rate threshold required by the minimum reception performance information for a certain frequency subband, then that frequency subband is dynamically added to the frequency hopping restriction information.

[0018] In other embodiments, the base station uses a pre-stored lookup table to obtain frequency hopping restriction information. For example, determining the user equipment frequency hopping restriction information includes... - Obtaining user equipment type information from the user equipment during control exchanges with the user equipment, and - Use the obtained user equipment type information to access and search lookup tables to retrieve frequency hopping restriction information assigned to the user equipment type information, or to retrieve a frequency hopping set that takes into account the frequency hopping restriction information assigned to the user equipment type information.

[0019] This embodiment is advantageous because it maintains a low amount of control traffic, which involves the exchange of information between the user equipment and the base transceiver when determining user equipment frequency hopping restriction information.

[0020] Another embodiment of the method includes an additional step of using user equipment frequency hopping restriction information to determine the frequency hopping time sequence. This allows for improved frequency hopping control schemes, such as when the base transceiver and different user equipment devices use the same frequency subband for wireless communication in parallel. The base station can control the frequency hopping time sequence for different user equipment devices to avoid using the same frequency subband for different user equipment devices simultaneously, as further illustrated below with respect to a set of embodiments.

[0021] In another preferred embodiment, determining the frequency hopping set, or determining the frequency hopping time sequence, or determining both the frequency hopping set and the frequency hopping time sequence, is additionally performed using bandwidth information, which indicates the frequency bandwidth occupied by individual frequency sub-bands to be used for transmitting radio signals to the user equipment. Using the bandwidth information, the distance between individual frequency sub-bands used for radio signal transmission can be advantageously adjusted, thereby optimizing the frequency hopping gain achieved by allocating frequency sub-bands for transmission, particularly with respect to the distance from frequencies covered by common internal interference.

[0022] In another set of embodiments described above, the method further includes using the determined frequency hopping control information to determine additional frequency hopping control information for one or more additional parallel transmissions of radio signals from the base station transceiver to the user equipment. The additional frequency hopping control information includes... - The frequency hopping set of the determined frequency hopping control information, and - A modified frequency hopping time order for the frequency subbands assigned to the frequency hopping set, wherein the modified frequency hopping time order for each additional parallel transmission is a cyclically shifted version of the determined frequency hopping time order of the frequency hopping control information.

[0023] According to this embodiment, parallel transmission from a base transceiver to a user equipment (UE) within a given allocated download band comprising different frequency sub-bands of the base transceiver better utilizes the transmission capacity of the download band in the frequency space at a given time, and can increase the amount of data transmitted to the UE within a given time span while complying with UE frequency hopping restriction information. Preferably, in this embodiment, the frequency sub-bands used in the frequency hopping scheme all have equal bandwidth, making the frequency hopping scheme for individual transmissions in the shifted version particularly simple to control.

[0024] In yet another embodiment, the method further includes - The determined frequency hopping control information is used to determine the scheduling control information for scheduling radio signal transmissions from the base transceiver to the user equipment, and - Provides the determined scheduling and control information for transmission to the user equipment in control communications associated with the transmission of radio signals to the user equipment.

[0025] Appropriately, the frequency subbands included in the frequency hopping control information are scheduled as an entity, i.e., as a scheduling information.

[0026] In another preferred embodiment, the method further includes the following steps: - Obtain coverage enhancement mode information associated with the user equipment, which indicates whether the user equipment is operating in a coverage enhancement mode defined by the radio communication standard; - The method is executed only when the obtained coverage enhancement mode information indicates that the user equipment is operating in a specific coverage enhancement mode.

[0027] In yet another preferred embodiment, the method further includes the following steps: - In a hybrid automatic repeat request scheme, the determined frequency hopping control information is used to determine the repeat control information, therefore the repeat control information includes frequency hopping control information for controlling the retransmission of radio signals from the base transceiver to the user equipment in response to receiving one or more repeat requests from the user equipment; and - Provides the determined retransmission control information for transmission to user equipment in control communications.

[0028] Therefore, this embodiment also includes retransmission under the Hybrid Automatic Repeat Request (HARQ) scheme in the frequency hopping scheme, using frequency hopping control information determined based on user equipment frequency hopping restriction information.

[0029] In another embodiment, the method includes performing a handover of the user equipment (UE) from the base transceiver to a second base transceiver. In this embodiment, UE frequency hopping restriction information is provided from the base transceiver to the second base transceiver. This allows signal transmission according to the UE frequency hopping restrictions to continue even after the handover, and avoids additional control communication between the UE and the second base transceiver to enable the implementation of the UE's individual frequency hopping scheme.

[0030] In a variation of this embodiment, during the handover process, the base transceiver also provides the second base transceiver with minimum reception performance information or coverage enhancement mode information, or both. This further improves the handover experience for user equipment.

[0031] The following description turns to a controller device according to a second aspect of the invention for controlling the transmission of radio signals from a base station transceiver of a cellular radio communication system to a user equipment.

[0032] The controller device includes a frequency hopping control unit configured to determine frequency hopping control information indicating a set of frequency subbands of a downlink channel in a cellular radio communication system for transmitting radio signals to a user equipment in a continuous radio signal band. Furthermore, the frequency hopping control information indicates the frequency hopping time sequence of the frequency subbands of the set of frequency hopping bands in the continuous radio signal band for transmitting radio signals to the user equipment.

[0033] Furthermore, the frequency hopping control unit is configured as follows: - Determine user equipment frequency hopping restriction information, which indicates one or more frequency sub-bands of downlink frequency bands to be excluded from the frequency hopping set due to signal reception disturbances at the user equipment caused by self-interference, and - Use user equipment frequency hopping restriction information to determine the frequency hopping set.

[0034] The controller device shares the advantages of the method according to the first aspect of the invention. In some embodiments, the controller device is implemented as a component to be integrated into a base transceiver. In other embodiments, the controller device is a separate component, used as a separate device external to the base transceiver.

[0035] In a preferred embodiment of the controller device, the frequency hopping control unit is further configured to - Obtain coverage enhancement mode information associated with the user equipment, which indicates whether the user equipment is operating in a coverage enhancement mode defined by the radio communication standard; - User equipment frequency hopping restriction information is determined only when the obtained coverage enhancement mode information indicates that the user equipment is operating in coverage enhancement mode; and - When the obtained coverage enhancement mode information indicates that the user equipment is not operating in coverage enhancement mode, determine the frequency hopping set without considering the user equipment frequency hopping restriction information.

[0036] In another preferred embodiment of the controller device, the frequency hopping control unit is further configured to - In the hybrid automatic repeat request scheme, the determined frequency hopping control information is used to determine the repeat control information, which therefore includes frequency hopping control information for controlling the retransmission of radio signals from the base transceiver to the user equipment in response to receiving one or more repeat requests from the user equipment; and - Provides the determined retransmission control information for transmission to user equipment in control communications.

[0037] According to a third aspect of the present invention, a base station transceiver is provided for use in a cellular radio communication system. The base station transceiver includes a controller device according to the second aspect or any embodiment thereof described above.

[0038] The base station transceivers share the advantages described in the context of the method according to the first aspect of the invention.

[0039] According to a fourth aspect of the present invention, a method for operating a user equipment of a cellular radio communication system is provided.

[0040] The method includes receiving frequency hopping control information indicating a set of frequency subbands of a downlink channel in a cellular radio communication system for a continuous radio signal segment intended for use by a user equipment to receive radio signals. The frequency hopping control information indicates the hopping time sequence of the frequency subbands of the set of frequency hopping segments for use by the user equipment to receive radio signals.

[0041] In a preferred embodiment of the method, the following additional step is included: providing the base transceiver with user equipment frequency hopping restriction information during a control exchange with the base transceiver prior to the base transceiver transmitting radio signals, which indicates one or more frequency subbands of the downlink frequency band to be excluded from the frequency hopping set.

[0042] In another embodiment, the method includes the additional step of receiving from the base transceiver minimum reception performance information for one or more frequency subbands during a control exchange with the base transceiver prior to the base transceiver transmitting radio signals, wherein the minimum reception performance information indicates the maximum reception bit error rate at the user equipment.

[0043] In another preferred embodiment, the method includes the following additional steps. - Provides the base transceiver with coverage enhancement mode information associated with the user equipment. The coverage enhancement mode indicates whether the user equipment is operating in a coverage enhancement mode defined by the radio communication standard, and - The method of the fourth aspect of the invention is performed only when the coverage enhancement mode information indicates that the user equipment is operating in coverage enhancement mode.

[0044] In yet another embodiment, the method includes the following additional steps: - Receive retransmission control information, including frequency hopping control information, in control communications from the base station transceiver. - Frequency hopping control information, including retransmission control information, is used to control the reception of one or more retransmissions of radio signals from the base transceiver to the user equipment in response to one or more retransmission requests transmitted from the user equipment to the base transceiver under the hybrid automatic repeat request scheme.

[0045] According to a fifth aspect of the invention, a computer program for controlling a base station transceiver is claimed. The computer program includes executable code for controlling the base station transceiver of a cellular radio communication system to control the transmission of radio signals to user equipment using the method of the first aspect of the invention. The computer program shares all the advantages of the method according to the first aspect of the invention.

[0046] According to a sixth aspect of the invention, a computer program for controlling user equipment is claimed. The computer program includes executable code for controlling user equipment used in a cellular radio communication system, according to the method of the fourth aspect of the invention, to control the reception of radio signals from a base station transceiver. The computer program shares all the advantages of the method according to the fourth aspect of the invention. Attached Figure Description

[0047] Further embodiments will now be described with reference to the accompanying drawings. In the drawings: Figure 1a A flowchart illustrating an embodiment of a method for operating a base station transceiver to control the transmission of radio signals to a user equipment according to the present invention is shown; Figure 1b It shows the use of Figure 1a The method shown generates an exemplary frequency hopping scheme; Figure 1c An exemplary illustration shows how self-interference affects the receiver sensitivity of a given user equipment; Figure 2 A flowchart illustrating an embodiment of a method for operating a base transceiver and user equipment to control the transmission of radio signals from the base transceiver to the user equipment; Figure 3 A flowchart of method 300 is shown, which is Figure 2 Alternative embodiments of method 200; Figure 4a A flowchart illustrating an embodiment of a method for determining additional frequency hopping control information for one or more additional parallel transmissions of radio signals from a base transceiver to a user equipment is shown. Figure 4b It shows the use of Figure 4a An exemplary frequency hopping scheme generated by the method; Figure 4c It shows the use of Figure 4a The method generates alternative exemplary frequency hopping schemes; Figure 5 A flowchart of the method is shown, which is Figure 2 Alternative embodiments of the method; Figure 6 A flowchart of the method is shown, which is Figure 2 Another alternative embodiment of the method; Figure 7 A flowchart is shown illustrating a method for using frequency hopping control information in a transmission in response to a hybrid automatic repeat request; Figure 8 A flowchart illustrating an embodiment of a method for performing a handover of a given user equipment from one base station transceiver to the next; and Figure 9 A base station transceiver 920 and a user equipment 910 according to the present invention are shown. Detailed Implementation

[0048] Figure 1a A flowchart illustrating an embodiment of a method 100 for operating a base station transceiver to control the transmission of radio signals to a user equipment according to the present invention is shown.

[0049] Both the base station transceiver and the user equipment are part of a cellular radio communication system. The method begins with an end marker 102 and includes an algorithm 103 for determining frequency hopping control information. The frequency hopping control information indicates the set of frequency subbands of the downlink band of the downlink channel of the cellular radio communication system for use in transmitting radio signals to the user equipment in a continuous radio signal segment. Furthermore, the frequency hopping control information indicates the hopping time sequence of the frequency subbands of the set of frequency hopping segments for transmitting radio signals to the user equipment.

[0050] Algorithm 103 includes two steps, 104 and 106. In step 104, user equipment frequency hopping restriction information is determined, which indicates one or more frequency sub-bands of the downlink frequency band to be excluded from the frequency hopping set.

[0051] exist Figure 1aIn the embodiment of method 100 shown, each frequency sub-band included in the frequency hopping set is indicated by a corresponding center frequency and a corresponding frequency sub-band width. For simplicity, it is assumed that all frequency sub-bands have the same width. However, this is not necessary in all cases. In other embodiments, at least one frequency sub-band has a narrower width than the other frequency sub-bands, for example, to extract affected frequency regions that may be used accordingly for other devices. In the next step 106, the frequency hopping set is determined based on the determined user equipment frequency hopping restriction information.

[0052] exist Figure 1b An example of a frequency hopping scheme 100' generated using method 100 is shown in the figure, and will be described below.

[0053] Figure 1b It shows the use of Figure 1a The exemplary frequency hopping scheme generated by method 100 shown.

[0054] exist Figure 1b In the diagram, the downlink channel bands 122 and 124 of the base transceiver and user equipment are shown as functions of frequencies indicated by the coordinate axes labeled "f".

[0055] Below frequency bands 122 and 124, the frequency hopping set and frequency hopping time sequence are shown, with the axis marked "t" indicating the frequency hopping time sequence and the axis marked "f" indicating the frequency hopping order.

[0056] In this example, the downlink frequency band is subdivided into five frequency sub-bands, of which only four are used, as shown in rectangles 126, 128, 130, and 132. Figure 1b As shown, at any given time, only one frequency sub-band is used for transmission. After a predetermined period of time, the frequency sub-band used for transmission is changed periodically. This illustration shows only a single cycle. In the next cycle, transmission continues with the lowest frequency sub-band, and the described pattern repeats.

[0057] like Figure 1b As shown, the frequency sub-bands corresponding to the frequency sub-bands between rectangles 128 and 130 are never used in the frequency hopping scheme. The frequency sub-bands not considered are those excluded from transmission due to self-interference, as indicated by the user equipment frequency hopping limit. Self-interference can be caused by functional modules, such as DC-DC converters or memory modules located near the receiver module, whose transmitted signals fall within the downlink channel's frequency band. The following will refer to... Figure 1c This describes the impact of self-interference on receiver sensitivity.

[0058] Figure 1c An exemplary illustration 100'' shows how self-interference can affect the receiver sensitivity of a given user equipment.

[0059] Exemplary Figure 100'' illustrates the noise level of a given user equipment as a function of frequency (represented by an axis labeled "f"), indicating the receiver sensitivity of the receiver module of the given user equipment. The unsuppressed noise level of the given user equipment is indicated by the upper noise level 140. It is well known that receiver sensitivity can be increased through accumulation, resulting in the lower noise level 142. The resulting increase in receiver sensitivity is due to the fact that the noise is temporally uncorrelated and therefore decreases due to destructive interference during the accumulation process.

[0060] However, if noise due to self-interference is present, this reduction will not occur, as illustrated using peaks 144.1, 144.2, and 144.3. The peaks 144.1, 144.2, and 144.3 in Figure 100'' are exemplary illustrations of noise caused by self-interference in the frequency range of the downlink band. Since noise originating from self-interference is time-dependent, these peaks are not affected by accumulation and remain at the accumulated noise level 146 and uncorrelated noise between peaks 144.1 and 144.3 after accumulation 142. Therefore, self-interference has a significant impact on receiver sensitivity and should be used... Figure 1a The method is to exclude it from the frequency hopping set.

[0061] Next, we will refer to Figures 2 to 8 To describe different embodiments of method 100.

[0062] Figure 2 A flowchart is shown of an embodiment of a method 200 for operating a base transceiver and user equipment to control the transmission of radio signals from the base transceiver to the user equipment.

[0063] Although Figure 1a The flowchart only shows the steps of method 100 performed by the base transceiver, but Figure 2 The steps performed by both the base transceiver and the user equipment are shown. Therefore, the flowchart is divided into left and right sides by dashed lines. The left side, also labeled "BST," indicates all steps of the method performed by the base transceiver, while the right side, also labeled "UE," indicates all steps performed by the user equipment.

[0064] Method 200 begins with end marker 202, followed by algorithm 204, which determines frequency hopping control information indicating the frequency hopping set of frequency subbands of a continuous radio signal segment to be used for transmitting radio signals from the base transceiver to the user equipment, and the frequency hopping time order of the frequency subbands of the frequency hopping set.

[0065] Algorithm 204 includes step 210, whereby the user equipment sends user equipment frequency hopping restriction information to the base transceiver during control switching. In the subsequent step 220, the base transceiver receives the user equipment frequency hopping restriction information.

[0066] In step 230, the user equipment processes the user equipment frequency hopping restriction information to determine the frequency hopping set for the frequency hopping control information. Method 200 stops at end marker 242.

[0067] In method 200, the user equipment frequency hopping restriction information is used only to determine the frequency hopping set. However, in other embodiments of the method, the base station alternatively or additionally uses the user equipment frequency hopping restriction information to determine the frequency hopping time order.

[0068] In other embodiments of this method, the user equipment (UE) does not send UE frequency hopping restriction information to the base transceiver; instead, it sends UE type information. The UE type information may be, for example, a part of the IMEI. In other embodiments, the UE type information corresponds to manufacturer and device type information, i.e., a TAC (Type Assignment Code).

[0069] In the next step, the base station then uses the obtained user equipment type information to access and search a lookup table on the server to retrieve frequency hopping restriction information assigned to that user equipment type information. In an alternative embodiment, the base transceiver uses the obtained user equipment type information to access and search a lookup table on the server to directly retrieve the frequency hopping set that takes into account the frequency hopping restriction information assigned to that user equipment type information.

[0070] In another embodiment of the method, in step 230, the base station transceiver considers bandwidth information and... Figure 2 The designation is "BWI". Bandwidth information indicates the frequency bandwidth occupied by a single frequency subband used to transmit radio signals to user equipment. In some embodiments of this method, bandwidth information is used to determine the frequency hopping set, or to determine the frequency hopping time order, or to determine both the frequency hopping set and the frequency hopping time order.

[0071] Figure 3 A flowchart of method 300 is shown, which is Figure 2 Alternative embodiments of method 200.

[0072] and Figure 2 The steps of method 200 and the steps of method 300 are labeled using the same reference numerals. For explanation of these features, the reader may refer to... Figure 2 The following description will only explain the features unique to Method 300.

[0073] As part of algorithm 304 for determining frequency hopping control information, method 300 includes additional step 350, wherein the base transceiver provides the user equipment with minimum receive performance information of frequency subbands of the downlink band, wherein the minimum receive performance information indicates the maximum receive bit error rate at the user equipment.

[0074] In step 310, the user equipment then determines the user equipment frequency hopping restriction information based on the minimum reception performance information and provides the user equipment frequency hopping restriction information to the base transceiver.

[0075] In methods 100, 200, and 300, at any given time, only one frequency sub-band of the downlink band is used to transmit radio signals from the base station transceiver to the user equipment. (See below for further details.) Figures 4a to 4c Describe alternative methods in which multiple sub-bands are used in parallel to transmit radio signals to two or more devices.

[0076] Figure 4a A flowchart illustrating an embodiment of a method for determining additional frequency hopping control information for one or more additional parallel transmissions of radio signals from a base transceiver to a user equipment is shown. This method is formulated from the perspective of the base transceiver.

[0077] Method 400 begins with end marker 402, followed by execution of the first step 410. In step 410, algorithm 103 of method 700 is executed to determine frequency hopping control information.

[0078] In the second step 420, additional frequency hopping control information is determined, wherein the additional frequency hopping control information includes a frequency hopping set of the determined frequency hopping control information and a modified frequency hopping time order allocated to the frequency subbands of the determined frequency hopping control information. Each modified frequency hopping time order for additional parallel transmission is a corresponding cyclically shifted version of the frequency hopping time order of the determined frequency hopping control information. Method 400 stops at end marker 432.

[0079] Next, we will refer to Figure 4b and Figure 4c Describes an exemplary frequency hopping scheme generated using method 400.

[0080] Figure 4b It shows the use of Figure 4a The exemplary frequency hopping scheme 400' generated by the method.

[0081] Frequency hopping scheme 400' illustrates the parallel transmission of radio signals to two different devices that support the same frequency hopping set.

[0082] With Figure 1b Frequency hopping scheme 400' is described in the same manner as frequency hopping scheme 100'. Figure 4bIn the upper part, the downlink channel bands 122 and 124 of the base transceiver and user equipment are shown as functions of frequency, with the coordinate axis marked "f" indicating frequency correlation.

[0083] exist Figure 4b The lower part of the diagram illustrates the time and frequency correlation of frequency hopping scheme 400' using a coordinate axis labeled "f" for frequency correlation and a coordinate axis labeled "t" for time correlation. The downlink frequency band is subdivided into five sub-bands. Transmission is performed using two parallel frequency hopping schemes. The first frequency hopping scheme is shown by rectangles 126, 128, 130, and 132, which correspond to... Figure 1b The frequency hopping scheme shown is 100'.

[0084] also, Figure 4b A second frequency hopping scheme is illustrated by rectangles 426, 428, 430, and 432. Transmissions in both the first and second frequency hopping schemes utilize the same set of frequency subbands. However, the first and second frequency hopping schemes differ in timing, such that the first frequency hopping scheme uses the same frequency subband that was used by the second frequency hopping scheme in a previous time step. In other words, the hopping timing order of the second frequency hopping scheme corresponds to the cyclically shifted hopping timing order of the first frequency hopping scheme.

[0085] Figure 4c The diagram shows a more complex combination of frequency hopping schemes. This frequency hopping scheme is also based on... Figure 4a Method 400 was used to generate it. However, in this case, in addition to the frequency hopping time order, the frequency hopping set was also modified. Figure 4c It shows the use of Figure 4a The alternative exemplary frequency hopping scheme 400'' generated by the method.

[0086] Except that rectangle 428 in the second frequency hopping scheme is replaced by rectangle 428', frequency hopping scheme 400'' is the same as frequency hopping scheme 400'. Rectangle 428' indicates that, as part of the second frequency hopping scheme, a frequency sub-band occupying the middle of frequency band 122 is used, which has not been used previously. Therefore, the frequency sub-band indicated by rectangle 130 is not used by the second frequency hopping scheme.

[0087] When receiving devices that transmit in parallel support different frequency subbands due to, for example, different internal interference sources, frequency hopping schemes based not only on different frequency hopping time sequences but also on different frequency hopping sets are particularly advantageous, such as... Figure 4c Frequency hopping scheme.

[0088] The previously described method only includes the steps required to determine the frequency hopping control information. The method below will describe additional steps that include preparing for radio signal transmission.

[0089] Figure 5 A flowchart of method 500 is shown, which is Figure 2 Alternative embodiments of method 200.

[0090] and Figure 2 The steps of method 200 are the same as those of method 500, and are labeled using the same reference numerals. For explanation of these features, the reader may refer to... Figure 2 The following description will only explain the features unique to Method 500.

[0091] As part of algorithm 504 for determining frequency hopping control information, method 500 includes additional steps 550 and 560.

[0092] In step 550, the base transceiver uses the determined frequency hopping control information to determine scheduling control information for scheduling radio signal transmissions from the base transceiver to the user equipment. Scheduling control information is required so that the user equipment knows which frequency subbands to listen to for radio signal transmissions.

[0093] In subsequent step 560, the base transceiver provides the determined scheduling control information for transmission to the user equipment in control communications associated with the transmission of radio signals to the user equipment.

[0094] In some cases, it is advantageous to use UE frequency hopping restriction information only when the UE is operating in coverage enhancement mode. The following will refer to... Figure 6 Describe this method.

[0095] Figure 6 A flowchart of method 600 is shown, which is Figure 2 Another alternative embodiment of the method.

[0096] and Figure 2 The steps of method 200 are the same as those of method 600, and are labeled using the same reference numerals. For explanation of these features, the reader may refer to... Figure 2 The following description will only explain the features unique to Method 600.

[0097] Before executing algorithm 204, the base transceiver verifies in step 620 whether the user equipment is operating in coverage enhancement mode. To this end, in step 610, the user equipment provides coverage enhancement mode information to the base transceiver, indicating whether the user equipment is operating in a coverage enhancement mode defined by the radio communication standard.

[0098] If the user equipment is operating in coverage enhancement mode, the base transceiver uses algorithm 204 to transmit radio signals to the user equipment (by...). Figure 6(The branch marked "Yes" indicates this). In this example, the coverage enhancement modes include CEmodeA and CEmodeB for Cat-M devices and CElevel1 to CElevel3 for NB-IoT devices.

[0099] Otherwise, the base station transceiver uses a standard frequency hopping algorithm to transmit radio signals to the user equipment (by...). Figure 6 The branch marked with "No" indicates the winner.

[0100] In an alternative embodiment of method 600, the user equipment provides information indicating which coverage enhancement the user equipment is using. In this embodiment, algorithm 204 is executed only when the user equipment is using a predetermined coverage enhancement mode.

[0101] In addition to standard radio signal transmission, the above method can also be used for radio signal transmission in response to hybrid automatic repeat request. See below for reference. Figure 7 An embodiment of this method is described.

[0102] Figure 7 A flowchart of a method 700 for using frequency hopping control information in a transmission in response to a hybrid automatic repeat request is shown. Method 700 is defined from the perspective of the base station transceiver. The steps taken by the user equipment are only implicitly mentioned.

[0103] Method 700 begins with end marker 702 and is executed in response to receiving one or more retransmission requests from a given user equipment.

[0104] In the first step 710 of method 700, algorithm 103 of method 100 is used to determine frequency hopping control information.

[0105] In the second step 720, under the hybrid automatic repeat request scheme, frequency hopping control information is used to determine the repeat control information.

[0106] In the final step 730 of method 700, the base station provides the determined retransmission control information for transmission to the user equipment in control communications. Method 700 stops at the end marker 742.

[0107] When a user equipment switches from one base station transceiver to another, it is advantageous to transfer frequency hopping control information from one base station transceiver to the next. The following will refer to... Figure 8 Describe this method.

[0108] Figure 8 A flowchart of a method 800 for performing a handover of a given user equipment from one base station transceiver to the next is shown.

[0109] Method 800 begins with end marker 802. In the first step 804, algorithm 103 of method 100 is executed to determine frequency hopping control information.

[0110] In the subsequent step 806, in the event of a handover, the base transceiver transmits the user equipment frequency hopping restriction information to the next base transceiver. This method is particularly advantageous for intra-frequency handovers.

[0111] In an alternative embodiment of method 800, algorithm 802 further includes the step of transmitting information about the control enhancement mode used by the user equipment. In still other embodiments of method 800, minimum reception performance information for determining user equipment frequency hopping limit information, signaled by the base transceiver, is also transmitted to the next base transceiver.

[0112] Finally, refer to Figure 9 This describes a base station transceiver and user equipment configured to perform one of the methods described above.

[0113] Figure 9 A base station transceiver 920 and a user equipment 910 according to the present invention are shown.

[0114] Figure 9 In the example, the user equipment is a cellular phone 910, which communicates with a base transceiver 920, which is depicted as a radio signal tower. Both the base transceiver 920 and the cellular phone 910 are part of a cellular radio communication system 900.

[0115] The base station transceiver 920 includes a controller device 920.1, which includes a frequency hopping control unit. The frequency hopping control unit is configured to determine frequency hopping control information indicating the set of frequency subbands of the downlink band of a cellular radio communication system for a continuous radio signal band to be used for transmitting radio signals to user equipment. Furthermore, the frequency hopping control information indicates the frequency hopping time sequence of the frequency subbands of the set of frequency hopping bands for the continuous radio signal band to be used for transmitting radio signals to user equipment.

[0116] Specifically, the frequency hopping control unit is configured to determine user equipment frequency hopping restriction information, which indicates one or more frequency sub-bands of downlink frequency bands to be excluded from the frequency hopping set due to signal reception disturbances at the user equipment caused by self-interference, and uses the user equipment frequency hopping restriction information to determine the frequency hopping set. Figure 9 In the example shown, the determination of the user equipment frequency hopping restriction information is performed by requesting the cellular phone 910 to provide user equipment frequency hopping restriction information in the control exchange before transmitting radio signals.

[0117] Cellular phone 910 includes a controller device 910.1 with a frequency hopping control unit configured to provide user equipment frequency limiting information to base transceiver 920 and subsequently receive frequency hopping control information from base station 920.

Claims

1. A method for operating a base station transceiver in a cellular radio communication system to control the base station transceiver to transmit radio signals to a user equipment, the method comprising: - Determine frequency hopping control information, which indicates the set of frequency hopping frequencies of frequency subbands in the downlink band of a cellular radio communication system for a continuous radio signal segment to be used for transmitting radio signals to a user equipment, and indicates the frequency hopping time sequence of the frequency subbands in the set of frequency hopping frequencies for the continuous radio signal segment to be used for transmitting radio signals to a user equipment; wherein - Determine the frequency hopping control information, including - Determine user equipment frequency hopping restriction information, which indicates one or more frequency sub-bands of the downlink frequency band to be excluded from the frequency hopping set, and - The frequency hopping set is determined using the user equipment frequency hopping restriction information.

2. The method according to claim 1, wherein, Determining user equipment frequency hopping restriction information includes receiving user equipment frequency hopping restriction information from the user equipment.

3. The method according to claim 1, wherein, Determining the frequency hopping limit information for user equipment includes signaling the user equipment to the minimum reception performance information of one or more frequency sub-bands, wherein the minimum reception performance information indicates the maximum received bit error rate at the user equipment.

4. The method according to claim 1, wherein, Determining user equipment frequency hopping restriction information includes - Obtaining user equipment type information from the user equipment during control exchanges with the user equipment, and - Use the obtained user equipment type information to access and search lookup tables to retrieve frequency hopping restriction information assigned to the user equipment type information, or to retrieve a frequency hopping set that takes into account the frequency hopping restriction information assigned to the user equipment type information.

5. The method according to any one of the preceding claims, further comprising: - Additionally, user equipment frequency hopping restriction information is used to determine the frequency hopping time sequence.

6. The method according to any one of claims 1 to 4, wherein Determining the frequency hopping set, or determining the frequency hopping time sequence, or determining both the frequency hopping set and the frequency hopping time sequence, is performed additionally using bandwidth information, which indicates the frequency bandwidth occupied by a single frequency subband to be used for transmitting radio signals to a user equipment.

7. The method according to any one of claims 1 to 4, further comprising: - Using the determined frequency hopping control information, further frequency hopping control information is determined for one or more additional parallel transmissions of radio signals from the base transceiver to the user equipment; wherein - The additional frequency hopping control information includes - The frequency hopping set of the determined frequency hopping control information, and - The modified frequency hopping time order of the frequency subbands assigned to the frequency hopping set, wherein, The modified frequency hopping time sequence used for each additional parallel transmission is a cyclically shifted version of the determined frequency hopping time sequence of the frequency hopping control information.

8. The method according to any one of claims 1 to 4, further comprising: - The determined frequency hopping control information is used to determine the scheduling control information for scheduling radio signal transmissions from the base transceiver to the user equipment, and - Provides the determined scheduling and control information for transmission to the user equipment in control communications associated with the transmission of radio signals to the user equipment.

9. The method according to any one of claims 1 to 4, further comprising: - Obtain coverage enhancement mode information associated with the user equipment, which indicates whether the user equipment is operating in a coverage enhancement mode defined by the radio communication standard; - The method of claim 1 shall be performed only if the obtained coverage enhancement mode information indicates that the user equipment is operating in a specific coverage enhancement mode as defined by the radio communication standard.

10. The method according to any one of claims 1 to 4, further comprising: - In a hybrid automatic repeat request scheme, the determined frequency hopping control information is used to determine the repeat control information, therefore the repeat control information includes frequency hopping control information for controlling the retransmission of radio signals from the base transceiver to the user equipment in response to receiving one or more repeat requests from the user equipment; and - Provides the determined retransmission control information for transmission to user equipment in control communications.

11. The method according to any one of claims 1 to 4, wherein - Performing a handover of user equipment from the base transceiver to the second base transceiver includes transmitting user equipment frequency hopping restriction information from the base transceiver to the second base transceiver.

12. A controller device for controlling the transmission of radio signals from a base station transceiver of a cellular radio communication system to a user equipment, the controller device comprising: - A frequency hopping control unit configured to determine frequency hopping control information, the frequency hopping control information indicating a set of frequency subbands of a downlink band of a cellular radio communication system for a continuous radio signal segment to be used for transmitting radio signals to a user equipment, and indicating the frequency hopping time sequence of the frequency subbands of the set of frequency hopping frequencies for the continuous radio signal segment to be used for transmitting radio signals to a user equipment; wherein - The frequency hopping control unit is configured as follows: - Determine user equipment frequency hopping restriction information, which indicates one or more frequency sub-bands of downlink frequency bands to be excluded from the frequency hopping set due to signal reception disturbances at the user equipment caused by self-interference, and - Use user equipment frequency hopping restriction information to determine the frequency hopping set.

13. The controller device according to claim 12, wherein, The frequency hopping control unit is also configured to - Obtain coverage enhancement mode information associated with the user equipment, which indicates whether the user equipment is operating in a coverage enhancement mode defined by the radio communication standard; - User equipment frequency hopping restriction information is determined only when the obtained coverage enhancement mode information indicates that the user equipment is operating in coverage enhancement mode; as well as - When the obtained coverage enhancement mode information indicates that the user equipment is not operating in coverage enhancement mode, determine the frequency hopping set without considering the user equipment frequency hopping restriction information.

14. The controller device according to claim 12 or 13, wherein, The frequency hopping control unit is also configured to - In the hybrid automatic repeat request scheme, the determined frequency hopping control information is used to determine the repeat control information, which therefore includes frequency hopping control information for controlling the retransmission of radio signals from the base transceiver to the user equipment in response to receiving one or more repeat requests from the user equipment. as well as - Provides the determined retransmission control information for transmission to user equipment in control communications.

15. A base transceiver for use in a cellular radio communication system, the base transceiver comprising a controller device according to any one of claims 12 to 14.

16. A computer program product including executable code, said code being executed by a processor for controlling a base transceiver of a cellular radio communication system according to the method of claim 1 to control the base transceiver to transmit radio signals to a user equipment.

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