Predictive early release of uplink retransmission memory based on uplink retransmission indicator

Abstract

The present application relates to predictive early release of uplink retransmission memory based on uplink retransmission indicator. Disclosed is a user equipment (UE) circuit, comprising: a radio frequency (RF) circuit configured to transmit uplink data; an uplink retransmission memory configured to store the transmitted uplink data for later retransmission; and a baseband circuit configured to: before receiving an uplink retransmission indicator from a base station, release the uplink retransmission memory based on a predicted value of the uplink retransmission indicator, wherein the uplink retransmission indicator indicates successful transmission of the uplink data stored in the uplink retransmission memory.

Description

Technical Field

[0001] This disclosure relates to a technique for early release of uplink retransmission memory (e.g., HARQ (Hybrid Automatic Repeat Request) memory bank) based on a predicted value of an uplink (UL) retransmission indicator (e.g., an uplink ACK / NACK associated with a previously transmitted Physical Uplink Shared Channel (PUSCH)). Background Technology

[0002] In 4G LTE, UL transmission is based on a synchronous UL HARQ procedure. Therefore, after the User Equipment (UE) has sent a UL PUSCH, the UE is guaranteed to receive the UL ACK / NACK (acknowledgment or non-acknowledgment) indication associated with the previously sent PUSCH within a predictable timing constraint (subframe n+4 for normal operation mode and subframe n+3 for latency reduction mode). However, in 5G NR (New Radio), to support ultra-flexible resource allocation on the network side, an asynchronous HARQ procedure has been introduced for UL, such as... Figure 1 As shown. For asynchronous UL HARQ in 5G NR, after UE 110 has sent ULPUSCH, the UE cannot guarantee that it will be able to send ULPUSCH within predictable timing constraints (from base station 120). After that, as Figure 1 (As shown) Receive associated UL ACK / NACK feedback.

[0003] The problem addressed in this disclosure is how to overcome the shortcomings of the 5G asynchronous UL HARQ procedure for the UE: the memory bank storing previously transmitted UL-SCH packets in the UL payload buffer cannot be turned off early for power saving or released early for other purposes. Attached Figure Description

[0004] The accompanying drawings are included to provide a further understanding of the embodiments. The drawings are incorporated in and constitute a part of this specification. The drawings illustrate embodiments and, together with the description, serve to explain the principles of the embodiments. Other embodiments and many anticipated advantages of the embodiments will be readily understood as they become clearer with reference to the following detailed description.

[0005] Figure 1 This is a schematic diagram of a communication system 100 showing UL HARQ transmission between a base station 120 and a user equipment (UE) 110.

[0006] Figure 2 This is a schematic diagram illustrating an exemplary multibody uplink HARQ memory 200 for storing UL-SCH packets for PUSCH transmission according to the present disclosure.

[0007] Figure 3 This is a schematic diagram illustrating an example process 300 for predicting PUSCH retransmissions using historical PUSCH retransmission calculations according to this disclosure.

[0008] Figure 4 This is an exemplary power graph 400 illustrating PUSCH retransmission prediction by exploring gradient information of historical PUSCH transmission power values ​​during closed-loop UL power control, according to the present disclosure.

[0009] Figure 5 This is a schematic diagram illustrating an example process 500 for calculating the PUSCH transmission power gradient according to this disclosure.

[0010] Figure 6 This is a schematic diagram illustrating an example process 600 for predicting PUSCH retransmissions by exploring high channel reciprocity in 5G NR FR2 operation, according to the present disclosure.

[0011] Figure 7 This is a schematic diagram illustrating an example of unwanted DL retransmission detection 700 according to this disclosure.

[0012] Figure 8 This is a schematic diagram illustrating an example process 800 for predicting PUSCH retransmissions by detecting unwanted DL retransmissions associated with the ACK bit sent to the target PUSCH, according to this disclosure.

[0013] Figure 9 This is a schematic diagram illustrating an example of a linearly weighted combination of four methods for joint PUSCH retransmission prediction 900 according to this disclosure.

[0014] Figure 10 This is a block diagram showing the UE circuit 1000 according to the present disclosure.

[0015] Figure 11 This is a schematic diagram illustrating an exemplary method 1100 for asynchronous uplink transmission according to the present disclosure. Detailed Implementation

[0016] The following detailed description will be taken with reference to the accompanying drawings, which form part of the detailed description and illustrate, by way of example, specific aspects in which the invention can be practiced. It should be understood that other aspects may be utilized and structural or logical changes may be made without departing from the scope of the invention. Therefore, the following detailed description should not be interpreted in a limiting sense, and the scope of the invention is defined by the appended claims.

[0017] The following terms, abbreviations, and symbols will be used in this article: 5G NR: 3GPP Fifth Generation New Radio Specification QoS: Quality of Service UL-SCH: Uplink Shared Channel UE: User Equipment gNB: gNodeB, a base station in 5G. LTE: Long Term Evolution RF: Radio Frequency UL: Uplink DL: Downlink SCH: Shared Channel PDSCH: Physical Downlink Shared Channel PUSCH: Physical Uplink Shared Channel FR2: Based on the frequency range of 5G NR 2 HARQ: Hybrid Automatic Repeat Request ACK: Confirmation NACK: Not confirmed NDI: New Data Indicator DCI: Downlink Control Information TPC: Transmit Power Control MCS: Modulation and Coding Scheme CSI-RS: Channel State Information Reference Signal SSB: Synchronization Signal Block It should be understood that comments made in connection with the described methods also apply to the corresponding device configured to perform the methods, and vice versa. For example, if specific method steps are described, the corresponding device may include a unit for performing the described method steps, even if the unit is not explicitly described or shown in the figures. Furthermore, it should be understood that, unless otherwise specifically indicated, features of the various exemplary aspects described herein may be combined with each other.

[0018] The techniques described herein can be implemented in wireless communication networks, particularly in communication networks based on mobile communication standards (e.g., 5G New Radio (NR) specifically for millimeter-wave data rates). These techniques can also be applied to LTE networks, particularly LTE-A and / or OFDM and subsequent standards. The methods are also applicable to high-speed communication standards from the Wi-Fi Alliance 802.11 family (e.g., 802.11ad and subsequent standards). The methods and apparatus described below can be implemented in electronic devices (e.g., cellular phones and mobile devices or wireless devices or user equipment communicating with radio cells (e.g., access points, base stations, gNodeBs and / or eNodeBs). The described apparatus can include integrated circuits (ICs) and / or passive devices and can be manufactured according to various technologies. For example, the circuits can be designed as logic integrated circuits, ASICs, analog integrated circuits, mixed-signal integrated circuits, optical circuits, memory circuits, and / or integrated passive devices.

[0019] Figure 1 This is a schematic diagram of a communication system 100 showing HARQ transmission between a base station 120 and a user equipment (UE) 110.

[0020] In 5G NR, to support highly flexible resource allocation on the network side, an asynchronous HARQ procedure has been introduced for UL. For asynchronous UL HARQ in 5G NR, after UE 110 has sent the UL PUSCH, the UE cannot guarantee that it will be able to complete the process within predictable timing constraints. Internally, it receives associated UL ACK / NACK feedback from base station 120, such as Figure 1 As shown.

[0021] This is because, in 5G NR, the New Data Indicator (NDI) for UL retransmission of previously sent PUSCH is carried by DCI format 0, which also indicates new PUSCH approval. This means that in 5G NR, the UE cannot release UL-SCH packets in the payload buffer until new PUSCH approval is received, as these packets may be needed for UL retransmission at any future time. Depending on the base station's internal scheduling, under adverse conditions, the UE may wait for several seconds until the NDI for the previously sent PUSCH is indicated.

[0022] The following describes a concept for overcoming the drawbacks of the asynchronous UL HARQ process for UEs in 5G (i.e., the memory bank storing previously transmitted UL-SCH packets in the UL payload buffer cannot be turned off early for power saving or released early for other purposes).

[0023] The following example calculation for a single UL CC (component carrier) case illustrates the dimensions of resource allocation: considering the maximum transport block size (TBS) per CC and the parallel execution of a maximum of 16 UL HARQ processes, it results in up to 52 * 16 = 832 KB of UL-SCH data that cannot be released early. This is highly inefficient for UE modem power saving because these storage banks carrying such a large amount of payload bits cannot be shut down early or reused for other purposes.

[0024] The basic concept of this disclosure is that the UE determines a prediction value by applying a prediction of PUSCH retransmission during asynchronous UL HARQ operation in 5G NR. When the UE predicts that the retransmission for a previous PUSCH is NONE (i.e., prediction value = 0), the UE can either release or shut down the storage containing the already transmitted UL-SCH packets in the UL payload buffer early. The PUSCH retransmission prediction can be based on the following sub-methods, and they can work together: (1) PUSCH retransmission prediction can be based on statistics of previously received PUSCH retransmission indices (UL NDI in DCI format 0) that are further weighted by the MCS of the associated PUSCH within a historical sliding time window (i.e., prediction value = X, and X is compared with a threshold).

[0025] (2) PUSCH retransmission prediction can be jointly determined by the estimated gradient of the PUSCH transmission power value during the closed-loop PUSCH power control process within the historical sliding time window (i.e., predicted value = Y, and Y compared with a threshold): a positive high gradient means that due to poor received signal quality at the gNB side, the gNB continuously sends TPC commands with positive power steps, requesting an increase in PUSCH transmission power. This information suggests that the UL channel is in poor condition. Accordingly, the retransmission probability of incoming ULPUSCH will increase, and vice versa.

[0026] (3) In particular, for 5G NR FR2 (mmWave band) operation, where UL / DL beam correspondence is assumed (attributed to high channel reciprocity based on analog beamforming of massive MIMO elements (antenna arrays) on both the UE and gNB sides), predictions can also be jointly determined based on beam quality measurements of specific DL resources (CSI-RS / SSBs) that are spatially associated with the transmitted PUSCH beam.

[0027] (4) In particular, the PDSCH ACK bit carried by the target PUSCH may not be correctly decoded on the gNB side in the following scenario: when the UE sends the PDSCH ACK bit but later receives the DL PDSCH retransmission flag, the target PUSCH jointly carries the DL HARQ feedback bit. This information can be explored, as it also suggests poor UL channel quality and therefore increases the likelihood of retransmission of the target PUSCH.

[0028] Furthermore, since erroneous predictions can be detected at the UE side by receiving the actual UL NDI from the network in the future, the UE can also dynamically disable predictions to ensure the robustness of the entire system. For example, if the count of erroneous predictions exceeds a predetermined threshold, the UE can disable predictions.

[0029] The advantage of this uplink retransmission prediction is that when no PUSCH transmission is predicted, the memory carrying already transmitted UL-SCH packets (up to 52KB per UL HARQ procedure) is released / disconnected early within the UL payload buffer. This reduces memory power while maintaining UL link robustness for 5G NR asynchronous UL HARQ scenarios.

[0030] Figure 2 This is a schematic diagram illustrating an exemplary multibody uplink HARQ memory 200 for storing UL SCH packets for PUSCH transmission according to the present disclosure.

[0031] The multi-bank uplink HARQ memory 200 is an example of an on-chip DRAM consisting of multiple memory banks 201, 202, 203, 204, 205, and 206 with contiguous addressing. In this example, each memory bank is 16KB, and each memory bank 201, 202, 203, 204, 205, and 206 is located in a different power domain. Each memory bank can be turned on and off independently. Obviously, if the memory banks storing the UL retransmission payload can be released and turned off earlier, the UE power consumption can be reduced. In an implementation, some memory banks (e.g., memory banks 201, 202, 203, and 204) can be allocated to a first power domain 210, while other memory banks (e.g., memory banks 205 and 206) can be allocated to a second power domain or to both a second and a third power domain. The power domains can be different and independently switchable.

[0032] During asynchronous UL HARQ operations in 5G NR, in order to release storage blocks (e.g., storage blocks 201, 202, 203, 204) containing already transmitted UL-SCH packets (up to 52KB per UL HARQ procedure) earlier, while still ensuring UL link robustness for PUSCH transmission, the UE can predict PUSCH retransmissions. (The above refers to...) Figure 1 Four sub-methods (1), (2), (3), and (4) are listed. These four sub-methods are further described below, and they can work together.

[0033] Figure 3 This is a schematic diagram illustrating an example process 300 for PUSCH retransmission prediction according to this disclosure.

[0034] Process or method 300 begins by sending (301) a new PUSCH (i.e., the target PUSCH). Then, a check (302) is performed to determine whether the UL-SCH packet size of the target PUSCH is greater than the threshold TH0. If not, method 300 falls back (303) to the regular UL HARQ process by waiting for the actual UL NDI (i.e., the UL NDI sent by the base station). If the result of check (302) is yes, the retransmission indexes for the N most recently sent PUSCHs are extracted (304). Then, the MCS information for the N most recently sent PUSCHs is extracted (305). The retransmission probability metric M is calculated (306), which is a weighted sum of the extracted retransmission indexes and the reciprocals of the associated MCS. Then, based on the calculated probability metric M, a protection timer is set (307) for the duration of T0. After this, a check (308) is performed after T0 to determine whether the target PUSCH still has not received an NDI and whether M is less than the threshold Th1. If the result of check (308) is negative, then method 300 jumps to box 303, that is, method 300 waits for the real UL NDI to fall back (303) to the regular UL HARQ procedure. Otherwise, if the result of check (308) is positive, then box 309 is executed, that is, the payload storage of the UL-SCH group associated with the target PUSCH is released early.

[0035] exist Figure 3 The first method (1) is shown in detail, in which the PUSCH retransmission prediction can be based on the statistics of the historically received PUSCH retransmission index within a sliding time window.

[0036] In one example, the UE can count the number of received retransmission indices (ranging from 0 to 3 for a maximum of 4 PUSCH retransmissions, with 0 meaning no retransmission) based on a fixed number of historically transmitted PUSCHs. Figure 3Box 306 in the diagram generates a retransmission probability metric. The UE can then compare the metric with a predetermined threshold to predict the retransmission status for the target PUSCH. When a retransmission is predicted to be avoidable, the UE can release the memory or turn it off early before receiving the corresponding NDI.

[0037] For the retransmission probability metric generation (box 306), each historical retransmission count can be further weighted by the inverse of the modulation and coding scheme (MCS) approved by the associated PUSCH. This is because a retransmission associated with a PUSCH that has erroneous decoding with a lower MCS indicates poorer UL channel quality. This information is relevant to predicting an increased retransmission probability.

[0038] Note that in Figure 3 In order to ensure system robustness, predictive decisions are not made immediately. Instead, a protection timer with a duration of T0 is set to check whether the associated real NDI can still be received from the gNB within T0. T0 can be adapted to a calculated retransmission probability metric M: the higher M is, the shorter T0 is.

[0039] In one example, the retransmission probability metric M can be calculated in the following form: Figure 3 Box 306 in the middle: Where N is derived from gNB (according to...) Figure 1 The number of most recent PUSCH approvals triggered by base station 120. An example value for N could be 20. G(i) is the retransmission index value associated with PUSCH approval i. According to the 5G NR standard, it ranges from 0 to 3. Specifically, G(i) = 0 indicates the initial transmission, while G(i) = 3 indicates the 3rd retransmission. Obviously, the higher the value of G(i), the worse the UL channel quality, which implies a higher probability of UL retransmission for the target PUSCH. MCS(i) is the MCS (Modulation and Coding Scheme) index associated with PUSCH approval i. The MCS index can be selected by the base station based on UL quality measurements on the gNB receiver side and indicated to the UE in the DCI (carried by the PDCCH). According to the 5G NR standard [38.214 Table 6.1.4.1-1], it ranges from 0 to 27. Clearly, when G(i)≠0, the lower the value of MCS(i), the worse the UL channel quality it reflects, which suggests a higher probability of UL retransmission for the target PUSCH.

[0040] The following example values ​​can be applied to Figure 3The process shown: Th0 = 32KB; T0 ranges from 1ms to 10ms. Th1 = 3; Note: Th1 can be further adapted to the Quality of Service (QoS) requirements of higher-layer application scenarios. Quality of Service is a description or measurement of the overall performance of a service (especially the performance perceived by network users). To quantitatively measure QoS, several relevant aspects of the network service are often considered (e.g., packet loss, bit rate, throughput, transmission delay, availability, jitter, etc.). QoS includes requirements for all aspects of connectivity (e.g., service response time, loss, signal-to-noise ratio, crosstalk, echo, interruptions, frequency response, loudness level, etc.). For example, for reliability-critical applications (e.g., secure messaging or HD video conferencing streaming), Th1 can be set to a lower value (e.g., Th1 = 1), prioritizing UL transmission robustness. For example, for less reliability-critical applications (e.g., FTP uploads), Th1 can be set to a higher value (e.g., Th1 = 6), prioritizing UE power saving.

[0041] Figure 4 This is an exemplary power graph 400 illustrating PUSCH retransmission prediction by exploring gradient information of historical PUSCH transmission power values ​​during closed-loop UL power control, according to the present disclosure. Figure 4 The PUSCH transmission power for the three gradient groups 401, 402, and 403 used for TPC commands is shown. In the first gradient group 401, the gradient is approximately zero, indicating good UL channel quality. In the second gradient group 402, the gradient is positively high (i.e., rising), indicating poor UL channel quality. In the third gradient group 403, the gradient is negatively high (i.e., falling), indicating good UL channel quality.

[0042] exist Figure 4 The second method (2) is shown in detail, in which the PUSCH retransmission prediction can be jointly determined by gradient estimation of the PUSCH transmission power value controlled by the TPC command received from the gNB within a historical sliding time window.

[0043] During closed-loop UL power control, based on the received UL signal quality measurement, the gNB iteratively sends TPC commands to the UE to increase or decrease the PUSCH transmission power. When the UE continuously receives PUSCH TPC commands with positive power steps, such as... Figure 4 As shown in (Group 402), this suggests that the UL channel quality is poor. This information can be explored to up-bias the PUSCH retransmission probability metric.

[0044] In the second method shown here, the PUSCH transmission power gradient can be calculated within a sliding time window, or the power value can be smoothed before estimating the gradient. Figure 4An example procedure for gradient estimation is shown.

[0045] Figure 5 This is a schematic diagram illustrating an example process 500 for calculating the PUSCH transmission power gradient according to this disclosure.

[0046] Process 500 begins in the first box 501: collecting PUSCH transmission power values ​​within the historical (i.e., previous) sliding time window. Then comes the second box 502: transforming the power values ​​from the dB domain to the linear domain. Following this is the third box 503: normalizing the linear domain power values ​​by the associated number of PUSCH-approved RBs (resource blocks). Next is the fourth box 504: applying a smoothing filter to the normalized power values ​​(e.g., via a low-pass FIR filter). Then comes the fifth box 505: calculating the power gradient of the smoothed power values ​​according to Equation (1): Note that in Equation (1), P(k) is the PUSCH transmission power value at time t(k), which has been transformed from the dB domain to the linear domain, normalized by the number of resource blocks of the associated PUSCH, and further smoothed and filtered.

[0047] Figure 6 This is a schematic diagram illustrating an example process 600 for predicting PUSCH retransmissions by exploring high channel reciprocity in 5G NR FR2 operation, according to the present disclosure.

[0048] Process 600 begins in the first box 601: receiving PUSCH approval (target PUSCH). Then, in the second box 602: identifying the DL spatial reference resource index (CSI-RS index or SSB index) spatially associated with the target PUSCH. Next, in the third box 603: transmitting the PUSCH using the exact same beam pattern used to receive the indicated spatial reference resource. Following this is the fourth box 604: estimating channel quality (e.g., path loss, delay spread, noise power) based on the indicated spatial reference resource signal received by the UE using the same beam pattern. Then, in the fifth box 605: based on the estimated channel quality, the UE determines a retransmission probability metric for the target PUSCH, such that the worse the channel quality, the higher the metric.

[0049] exist Figure 6 The third method (3) is shown in detail. Specifically, for 5G NR FR2 (frequency range 2, mmWave band) that achieves high channel reciprocity due to narrow beamforming by massive MIMO elements, PUSCH retransmission prediction can be jointly determined by DL channel quality measurements of a specific DL reference signal that is spatially associated with the target PUSCH.

[0050] According to the 3GPP 5G NR uplink beam management framework for FR2 operation, when the UE reports beam correspondence capability to the gNB, the gNB can dynamically indicate the DL spatial reference resource (SSB or CSI-RS resource) spatially associated with the PUSCH approval. Accordingly, the UE must generate a beam pattern identical to that used for receiving the indicated DL spatial reference resource to transmit the associated PUSCH. This process results in high channel reciprocity. PUSCH retransmission probability metrics can also be jointly determined based on DL quality measurements for this specific DL resource (SSB or CSI-RS) indicated as spatially associated with the target PUSCH. For example, channel quality metrics measured from such DL spatial reference resources could be: 1) path loss estimation; 2) delay spread estimation; or 3) noise power estimation. By taking into account the high channel reciprocity in FR2, these also reflect the signal attenuation level, signal reflection level, and noise level of the UL beam transmitting the associated PUSCH. Figure 6 The detailed process is shown in the figure.

[0051] Figure 7 This is a schematic diagram illustrating an example of unwanted DL retransmission detection 700 according to this disclosure.

[0052] In block 701, the UE transmits a UL PUSCH carrying the DL ACK bit associated with the DL HARQ procedure. In block 702, the UE receives a DL PDCCH (with the NDI field in the DCI being 0) indicating a DL retransmission associated with the same DL HARQ procedure. A mismatch 703 exists between block 701 and block 702: an unwanted DL retransmission is detected. This is because the DL retransmission in block 702 contradicts the previously indicated DL ACK bit carried by the PUSCH in block 701, meaning the indicated DL ACK bit (carried by the PUSCH transmitted by the UE) cannot be decoded by the gNB. This further suggests poor UL channel quality.

[0053] exist Figure 7 The fourth method (4) is shown in detail. Specifically, for a transmitted PUSCH that jointly carries DL PDSCH ACK bits, PUSCH retransmissions can be jointly determined by later detecting unwanted DL retransmissions associated with ACK bits carried by the same PUSCH.

[0054] For the DL HARQ procedure, the UE needs to send DL PDSCH ACK / NACK bits to the gNB. These can be carried by the PUSCH or PUCCH. If it is decoded as NACK on the gNB side, the DL PDSCH retransmission flag can be indicated to the UE later (it has a different DCI format than the UL retransmission indicator). When the UE has successfully decoded the previous DL PDSCH and the target PUSCH carries the associated DL ACK bits, for poor UL channel quality, the network may not be able to decode the DL ACK bits in the received PUSCH and may schedule an unwanted DL retransmission to the UE. The UE can detect this situation because it remembers the previous DL PDSCH decoding state. When the UE has detected an unwanted DL retransmission, it can be assumed that the target PUSCH used to carry the associated ACK bits is in poor UL channel quality. This information can be explored to modify the retransmission probability of that target PUSCH. Figure 8 The diagram illustrates an example process for this unwanted DL retransmission detection 700.

[0055] Figure 8 This is a schematic diagram illustrating an example process 800 for predicting PUSCH retransmissions by detecting unwanted DL retransmissions associated with DL ACK bits sent by the target PUSCH, according to the present disclosure.

[0056] In box 801, a new PUSCH (target PUSCH) is sent. Then, a check 802 is performed to determine if the PUSCH contains DL ACK bits. If the result is no, the process jumps back to box 801. If the result is yes, a further check 803 is performed: whether unwanted DL retransmissions (associated with the DL ACK bits sent by the target PUSCH) have been received. If the result is no, the process jumps back to box 801. If the result is yes, in box 804, the value of the retransmission probability metric for the target PUSCH is incremented.

[0057] The above text is about Figures 1 to 8The four methods described can be used to predict PUSCH retransmissions independently or jointly. For joint operation, as an example, the PUSCH retransmission probability metrics from each method can be weighted by different weighting factors and then linearly combined to generate a combined retransmission probability metric for target PUSCH approval. The combined retransmission probability metric can be compared to a predetermined threshold: when it is above the threshold, this means the PUSCH retransmission is predicted as true, and accordingly, the target PUSCH UL payload bits still need to be held in the UL HARQ buffer; otherwise, the PUSCH retransmission is predicted as false, and accordingly, the HARQ memory containing the target UL payload bits can be released early for other uses or shut down. The following... Figure 9 An example is shown below.

[0058] Figure 9 This is a schematic diagram illustrating an example of a linearly weighted combination of four methods for joint PUSCH retransmission prediction 900 according to this disclosure.

[0059] As mentioned above Figures 1 to 8 The method described (1) derives a first metric Ml weighted by a first weight Wl (901). This is as described above regarding... Figures 1 to 8 The second metric M2 derived by the described method (2) is weighted by a second weight W2 (902). As stated above regarding... Figures 1 to 8 The third metric M3 derived by the described method (3) is weighted by a third weight W3 (903). As stated above regarding... Figures 1 to 8 The fourth metric M4 derived by the described method (4) is weighted (904) by a fourth weight W4. All four weighted metrics are combined (e.g., added) by a combiner 905 (e.g., adder 905) into a combined metric M_comb 911. A comparator 906 compares the combined metric M_comb 911 with a threshold TH 912. If the PUSCH retransmission is predicted as true, the result 913 of the comparator 906 is true; then the UL payload can be stored in the UL HARQ buffer. If the PUSCH retransmission is predicted as false, the result 913 of the comparator 906 is false; then the UL payload can be released from the UL HARQ buffer.

[0060] Since erroneous predictions can be detected at the UE side by receiving the actual NDI from the network later, the UE can dynamically disable predictions if the count of erroneous predictions exceeds a predetermined threshold, thus ensuring the robustness of the entire system. Note that the retransmission prediction of the UL NDI verification PUSCH associated with the same PUSCH approved can be determined by comparing the prediction with the retransmission prediction of the UL NDI verification PUSCH received later from the base station.

[0061] Threshold 912 ( Figure 9The TH value can also be dynamically adapted to the reliability requirements (e.g., quality requirements) of higher-layer applications. As an example, for high-reliability-critical applications (e.g., secure messaging or HD video conferencing streaming), TH can be set to a lower value, prioritizing UL transmission robustness. In another example, for less reliability-critical applications (e.g., FTP uploads), TH can be set to a higher value, prioritizing UE power saving.

[0062] Figure 10 This is a block diagram showing the UE circuit 1000 according to the present disclosure.

[0063] The UE circuit 1000 includes: a radio frequency (RF) circuit 1001 configured to transmit uplink data 1004; an uplink retransmission memory 1003 configured to store the transmitted uplink data 1004 for later retransmission; and a baseband circuit 1002. The baseband circuit 1002 is configured to release the uplink retransmission memory 1003 based on a predicted value of the uplink retransmission indicator before receiving it from the base station. The uplink retransmission indicator indicates successful transmission of the uplink data 1004 stored in the uplink retransmission memory 1003. The UE circuit 1000 can be implemented as follows: Figure 1 In the UE 110 shown, an uplink retransmission indicator can be received from the base station 120, such as... Figure 1 As shown in the scenario, the uplink retransmission memory 1003 may include, for example... Figure 2 The memory configuration shown is 200. Prediction of uplink retransmission indicators can be performed, as described above regarding... Figures 2 to 9 As described. The uplink retransmission memory 1003 can be an in-circuit memory of the baseband circuit 1002, or it can be implemented as an external memory.

[0064] Specifically, uplink retransmission indicators can be predicted based on statistics from previously received uplink retransmission indices. These statistics can be based on uplink retransmission indices that indicate the number of retransmissions of the same uplink data, for example, as mentioned above. Figure 3 As described in method (1).

[0065] Uplink retransmission indicators can be predicted based on statistics of previously received uplink retransmission indices, weighted by the modulation and coding scheme (MCS) of the uplink data associated with each uplink retransmission index, for example, as mentioned above. Figure 3 As described in method (1).

[0066] Uplink retransmission indicators can be predicted based on gradient measurements of uplink transmission power changes determined for previously received uplink transmission power control (TPC) commands, for example, as described above regarding... Figure 4 and Figure 5 As described in method (2), the baseband circuit 1002 can release the uplink retransmission memory 1003 for gradient measurements indicating a negative gradient and retain the uplink retransmission memory 1003 for gradient measurements indicating a positive gradient.

[0067] Uplink retransmission indicators can be predicted based on downlink channel quality measurements for a specific downlink reference signal that is spatially associated with the transmitted uplink data 1004, for example, as described above regarding... Figure 6 As described in method (3), the baseband circuit 1002 is configured to determine a downlink channel quality measurement based on at least one of the following: a path loss estimate, a delay spread estimate, or a noise power estimate for a specific downlink reference signal, for example, as described above regarding Figure 6 As described in method (3).

[0068] The baseband circuit 1002 can predict the uplink retransmission indicator by comparing the downlink acknowledgment bit (DL ACK) carried by the uplink data transmission (PUSCH) with a later received downlink retransmission that violates the indicated downlink acknowledgment bit, for example, as described above regarding Figure 7 and Figure 8 As described in method (4).

[0069] The baseband circuit 1002 can release the uplink retransmission memory 1003 based on a metric, for example, as described above regarding... Figure 9 As described above, metric 911 weights at least one of the following: statistics on previously received uplink retransmission indices, for example, as mentioned above. Figure 3 As described in method (1); the gradient information determined for the previously received uplink transmission power control (TPC) command, for example, as described above regarding Figure 4 and Figure 5 As described in method (2); for downlink channel quality measurements of a specific downlink reference signal indicated as spatially associated with the transmitted uplink data, for example, as described above regarding Figure 6 As described in method (3); and a downlink retransmission indicator indicating successful transmission of downlink data, for example, as described above regarding Figure 7 and Figure 8 As described in method (4).

[0070] The baseband circuit 1002 is configured to release the uplink retransmission memory 1003 when the metric 911 is lower than the threshold 912, and to retain the uplink retransmission memory 1003 when the metric 911 is higher than the threshold 912.

[0071] The baseband circuit 1002 can adjust the threshold 912 based on the Quality of Service (QoS) requirements of higher-layer applications. Specifically, if the QoS requirements decrease, the baseband circuit 1002 can reduce the threshold 912 used for QoS-critical applications.

[0072] The baseband circuit 1002 can disable the prediction of the uplink retransmission indicator when a threshold number of incorrect predictions is detected. Specifically, the baseband circuit 1002 can base the prediction of the uplink retransmission indicator predicted by the UE circuit 1000 with the prediction from the base station 120 (see [link]). Figure 1 The error prediction result is determined by comparing the received uplink retransmission indicators associated with the same transmitted uplink data 1004.

[0073] The uplink retransmission memory 1003 may include multiple memory banks, such as those mentioned above. Figure 2 As described. Each memory bank can be in an independent power domain and can be powered down individually if the stored uplink retransmission data 1004 is released within the memory bank.

[0074] The baseband circuit 1002 can handle multiple asynchronous Hybrid Automatic Repeat Request (HARQ) processes according to the 5G New Radio specification, for example, as mentioned above. Figure 1 and Figure 2 As described.

[0075] Figure 11 This is a schematic diagram illustrating an exemplary method 1100 for asynchronous uplink transmission according to the present disclosure.

[0076] Method 1100 includes: sending (1101) uplink data (e.g., as about Figure 10 The described uplink data 1004). Method 1100 includes: storing (1102) the transmitted uplink data 1004 in an uplink retransmission memory (e.g., as per the description of uplink data 1004). Figure 10 The described memory 1003 is used for later retransmission. Method 1100 includes: before receiving an uplink retransmission indicator from the base station, releasing (1103) the uplink retransmission memory 1003 based on a predicted value of the uplink retransmission indicator, the uplink retransmission indicator indicating successful transmission of uplink data stored in the uplink retransmission memory. This can be described as above regarding... Figures 2 to 10 It performs prediction of uplink retransmission indicators as described.

[0077] Method 1100 may include: predicting an uplink retransmission indicator based on statistics of previously received uplink retransmission indices. Method 1100 may also include: determining statistics of previously received uplink retransmission indices based on uplink retransmission indices that indicate the number of retransmissions of the same uplink data.

[0078] Method 1100 may include: releasing the uplink retransmission memory based on a weighted metric of at least one of the following: statistics of previously received uplink retransmission indices, for example, as described above regarding Figure 3 As described in method (1); the gradient information determined for the previously received uplink transmission power control (TPC) command, for example, as described above regarding Figure 4 and Figure 5 As described in method (2); for downlink channel quality measurements of a specific downlink reference signal indicated as spatially associated with the transmitted uplink data, for example, as described above regarding Figure 6 As described in method (3); and a downlink retransmission indicator indicating successful transmission of downlink data, for example, as described above regarding Figure 7 and Figure 8 As described in method (4).

[0079] This disclosure also supports computer program products that include computer-executable code or computer-executable instructions, which, when executed, cause at least one computer to perform the execution and computation frames described herein, as well as the methods and processes described above. The computer program product may include a non-transitory readable storage medium storing program code thereon for use by a processor, the program code including instructions for performing the methods or computation frames as described above.

[0080] The following illustrates two exemplary implementations of the uplink retransmission memory described above. The first example implementation describes average memory fill savings. The second example implementation describes reduced memory power.

[0081] Average memory fill savings depend on the use case. For example, in a use case for uplink video streaming (e.g., UHD video conferencing calls in an eMBB scenario), assuming 4K (2160p) video, a transmission bit rate of around 40 Mbps (information bits after video compression but before channel coding) is required. Furthermore, for video streaming scenarios at 20 milliseconds, consider typical PUSCH scheduling (UL transmissions for streaming applications are not back-to-back because a constant time gap is reserved for video codec processing). The UL payload data (UL-SCH) size can then be estimated in the following form: Estimated UL-SCH bit size per PUSCH byte.

[0082] This means that in this scenario, without UL retransmission prediction according to this disclosure, 800KB of memory must be continuously occupied in the UL HARQ buffer. This is because, due to asynchronous UL HARQ in 5G NR, the UL ACK / NACK flag associated with the previous PUSCH transmission is embedded in the next PUSCH approval scheduled 20 milliseconds later. Therefore, when UL video streaming is performed, the UE cannot release the 800KB UL-HARQ payload bits at all. When using UL retransmission prediction according to this disclosure, the UE can immediately release the corresponding payload memory when a good UL condition is predicted.

[0083] Regarding the reduction in memory power (second example implementation), the saved memory power is the leakage power resulting from the reduced on-time of the memory bank storing those UL-SCH bits for UL retransmission. The following exemplary figures can be applied: at 14nm technology, for a 64KB DRAM bank on, the leakage power is estimated to be approximately x mW (x depends on the hardware). Using the same use case as the first example implementation (UL video streaming), for each 20ms time window (the UL scheduling interval for video streaming), without this optimization, the memory leakage power used to store the 800KB UL-SCH bits is estimated as follows: Under this optimization, the memory bank used to hold the large number of UL-SCH bits can be shut down immediately after the PUSCH transmission. Therefore, the equivalent memory leakage power within the 20ms timing window is estimated as follows: The memory leakage power saved by applying the UL retransmission prediction according to this disclosure is the difference between the two aforementioned leakage powers, which can be calculated as follows: In addition to the UL video streaming use cases mentioned above, another use case exists where UL retransmission prediction based on this disclosure can also be beneficial: namely, in C-DRX (Connectivity Mode DRX) operation. This allows the UE to be scheduled to send a PUSCH before the C-DRX off duration. Since UL HARQ in 5G NR is asynchronous, the UE must retain the payload bits for the entire C-DRX off duration in memory, and can only release this memory after the UE has received a retransmission flag after returning to the on duration. Note that the C-DRX off duration can be very long (up to 2.56 seconds). With UL retransmission prediction, the UE can release this memory earlier.

[0084] Example The following examples are further embodiments. Example 1 is a user equipment (UE) circuit, including: a radio frequency (RF) circuit configured to transmit uplink data; an uplink retransmission memory configured to store the transmitted uplink data for later retransmission; and a baseband circuit configured to: release the uplink retransmission memory based on a predicted value of the uplink retransmission indicator before receiving an uplink retransmission indicator from a base station, wherein the uplink retransmission indicator indicates successful transmission of the uplink data stored in the uplink retransmission memory.

[0085] In Example 2, the subject of Example 1 may optionally include: predicting the uplink retransmission indicator based on statistics of previously received uplink retransmission indices.

[0086] In Example 3, the subject of Example 2 may optionally include: the statistics of the previously received uplink retransmission index are based on the uplink retransmission index indicating the number of retransmissions of the same uplink data.

[0087] In Example 4, the subject matter of Example 1 or 2 may optionally include: predicting the uplink retransmission indicator based on statistics of previously received uplink retransmission indices weighted by the modulation and coding scheme (MCS) of the uplink data associated with each uplink retransmission index.

[0088] In Example 5, the subject matter of Example 1 or 2 may optionally include: predicting the uplink retransmission indicator based on gradient measurements of uplink transmission power changes determined for a previously received uplink transmission power control (TPC) command.

[0089] In Example 6, the subject matter of Example 5 may optionally include: the baseband circuitry is configured to: release the uplink retransmission memory for gradient measurements indicating a negative gradient, and retain the uplink retransmission memory for gradient measurements indicating a positive gradient.

[0090] In Example 7, the subject matter of Example 1 or 2 may optionally include: predicting the uplink retransmission indicator based on downlink channel quality measurements for a specific downlink reference signal that is spatially associated with the transmitted uplink data.

[0091] In Example 8, the subject matter of Example 7 may optionally include: the baseband circuitry is configured to determine the downlink channel quality measurement based on at least one of the following: path loss estimation, delay spread estimation, or noise power estimation of the particular downlink reference signal.

[0092] In Example 9, the subject matter of Example 1 or 2 may optionally include: the baseband circuitry is configured to predict the uplink retransmission indicator by comparing a downlink acknowledgment bit (DL ACK) carried by the uplink data transmission (PUSCH) with a later received downlink retransmission that violates the indicated downlink acknowledgment bit.

[0093] In Example 10, the subject matter of Example 1 or 2 may optionally include: the baseband circuitry being configured to release the uplink retransmission memory based on a weighted metric of at least one of the following: statistics of previously received uplink retransmission indices, gradient information determined for previously received uplink transmission power control (TPC) commands, downlink channel quality measurements for a specific downlink reference signal spatially associated with transmitted uplink data, and a downlink retransmission indicator indicating successful transmission of downlink data.

[0094] In Example 11, the subject of Example 10 may optionally include: the baseband circuitry is configured to: release the uplink retransmission memory when the metric is below a threshold, and retain the uplink retransmission memory when the metric is above the threshold.

[0095] In Example 12, the subject of Example 11 may optionally include: the baseband circuit is configured to adjust the threshold based on the Quality of Service (QoS) requirements of higher-layer applications.

[0096] In Example 13, the subject of Example 12 may optionally include: the baseband circuitry is configured to reduce the threshold for QoS-critical applications if the QoS requirements are reduced.

[0097] In Example 14, the subject matter of Example 1 or 2 may optionally include: the baseband circuit is configured to: disable prediction of the uplink retransmission indicator when a threshold number of incorrect predictions are detected.

[0098] In Example 15, the subject matter of Example 14 may optionally include: the baseband circuitry is configured to: determine an erroneous prediction result based on a comparison between the uplink retransmission indicator predicted by the UE circuitry and the uplink retransmission indicator later received from the base station associated with the same transmitted uplink data.

[0099] In Example 16, the subject matter of Example 1 or 2 may optionally include: the uplink retransmission memory includes multiple memory banks, wherein each memory bank is in an independent power domain and can be individually powered off if the stored uplink retransmission data is released within the memory bank.

[0100] In Example 17, the subject matter of Example 1 or 2 may optionally include: wherein the baseband circuit is configured to: process multiple asynchronous Hybrid Automatic Repeat Request (HARQ) processes in accordance with the 5G New Radio specification.

[0101] Example 18 is a processing circuit for a user equipment (UE), wherein the UE includes: a radio frequency (RF) transmitter for transmitting uplink data; and an uplink retransmission memory for storing the transmitted uplink data for later retransmission, wherein the processing circuit is configured to: release the uplink retransmission memory based on a predicted value of the uplink retransmission indicator before receiving an uplink retransmission indicator from a base station, the uplink retransmission indicator indicating successful transmission of the uplink data stored in the uplink retransmission memory.

[0102] In Example 19, the subject matter of Example 18 may optionally include: the processing circuitry being configured to release the uplink retransmission memory based on a weighted metric of at least one of the following: statistics of previously received uplink retransmission indices, gradient information determined for previously received uplink transmission power control (TPC) commands, downlink channel quality measurements for a specific downlink reference signal indicated as spatially associated with transmitted uplink data, and a downlink retransmission indicator indicating successful transmission of downlink data.

[0103] In Example 20, the subject of Example 19 may optionally include: the processing circuitry is configured to: release the uplink retransmission memory when the metric is below a threshold, and retain the uplink retransmission memory when the metric is above the threshold.

[0104] Example 21 is a user equipment (UE) including: radio frequency (RF) circuitry configured to transmit a physical uplink shared channel (PUSCH); an uplink hybrid automatic repeat request (HARQ) store configured to store the PUSCH transmission; and baseband circuitry configured to: release the uplink HARQ store from the PUSCH transmission based on a predicted value of the NDI associated with the PUSCH transmission before receiving a new data indicator (NDI) from a base station, the NDI indicating a successful transmission of the PUSCH stored in the HARQ store.

[0105] In Example 22, the subject matter of Example 21 may optionally include: the baseband circuitry being configured to: release the uplink HARQ memory from the PUSCH transmission based on a weighted metric of at least one of the following: statistics of a previously received uplink retransmission index, gradient information determined for a previously received uplink transmission power control (TPC) command, downlink channel quality measurement for a specific downlink reference signal spatially associated with the PUSCH transmission, and a physical downlink shared channel (PDSCH) acknowledgment bit associated with the PUSCH transmission, the PDSCH acknowledgment bit indicating a successful PDSCH transmission.

[0106] Example 23 is a method for asynchronous uplink transmission, the method comprising: transmitting uplink data; storing the transmitted uplink data in an uplink retransmission memory for later retransmission; and releasing the uplink retransmission memory based on a predicted value of the uplink retransmission indicator before receiving an uplink retransmission indicator from a base station, the uplink retransmission indicator indicating successful transmission of the uplink data stored in the uplink retransmission memory.

[0107] In Example 24, the subject of Example 23 may optionally include: predicting the uplink retransmission indicator based on statistics of previously received uplink retransmission indices.

[0108] In Example 25, the subject of Example 24 may optionally include: determining statistics of the previously received uplink retransmission index based on an uplink retransmission index indicating the number of retransmissions of the same uplink data.

[0109] In Example 26, the subject matter of Example 24 or 25 may optionally include: releasing the uplink retransmission memory based on a weighted metric of at least one of the following: statistics of previously received uplink retransmission indices, gradient information determined for previously received uplink transmission power control (TPC) commands, downlink channel quality measurements for a specific downlink reference signal indicated as spatially associated with transmitted uplink data, and a downlink retransmission indicator indicating successful transmission of downlink data.

[0110] Example 27 is an apparatus for asynchronous uplink transmission, the apparatus comprising: a module for transmitting uplink data; a module for storing the transmitted uplink data in an uplink retransmission memory for later retransmission; and a module for releasing the uplink retransmission memory based on a predicted value of the uplink retransmission indicator before receiving an uplink retransmission indicator from a base station, the uplink retransmission indicator indicating successful transmission of the uplink data stored in the uplink retransmission memory.

[0111] In Example 28, the subject of Example 27 may optionally include: a module for predicting the uplink retransmission indicator based on statistics of previously received uplink retransmission indexes indicating the number of retransmissions of the same uplink data.

[0112] Example 29 is a system-on-a-chip including: radio frequency (RF) circuitry configured to transmit uplink data; an uplink retransmission memory configured to store the transmitted uplink data for later retransmission; and baseband circuitry configured to: release the uplink retransmission memory based on a predicted value of the uplink retransmission indicator before receiving an uplink retransmission indicator from a base station, the uplink retransmission indicator indicating successful transmission of the uplink data stored in the uplink retransmission memory.

[0113] In Example 30, the subject of Example 29 may optionally include: the baseband circuitry is configured to predict the uplink retransmission indicator based on statistics of previously received uplink retransmission indices indicating the number of retransmissions of the same uplink data.

[0114] Example 31 is a computer-readable non-transitory medium having stored computer instructions thereon, which, when executed by a computer, cause the computer to perform the method as described in any one of Examples 23 to 26.

[0115] Furthermore, while specific features or aspects of this disclosure may have been disclosed only with respect to one of several implementations, such features or aspects may be combined with one or more other features or aspects of other implementations as desired and advantageous for any given or particular application. Additionally, where the terms “comprising,” “having,” “with,” or other variations thereof are used in the Detailed Description or claims, these terms are intended to be inclusive in a manner similar to the term “comprising.” Furthermore, it should be understood that aspects of this disclosure may be implemented in discrete circuits, partially integrated circuits, or fully integrated circuits or programming devices. Moreover, the terms “exemplary,” “for example,” and “likely” are meant only as examples and not as best or preferred.

[0116] While specific aspects have been shown and described herein, those skilled in the art will understand that various alternative and / or equivalent implementations may be used to replace the specific aspects shown and described without departing from the scope of this disclosure. This application is intended to cover any modifications or variations of the specific aspects discussed herein.

[0117] Although the elements in the appended claims are set forth in a particular order with corresponding markings, these elements are not necessarily intended to be limited to being implemented in that particular order unless the statement of the claims otherwise implies a particular order for implementing some or all of these elements.

Claims

1. One or more computer-readable media, the computer-readable media containing instructions that, in response to being executed by one or more processors, cause the one or more processors to: Uplink data is stored in the uplink retransmission memory; and Based on the predicted uplink retransmission value, the uplink retransmission memory is released regardless of whether an uplink retransmission indicator is received from the base station. The uplink retransmission indicator indicates the successful transmission of uplink data stored in the uplink retransmission memory.

2. The computer-readable medium according to claim 1, wherein, The predicted value is predicted based on statistics from previously received uplink retransmission indexes.

3. The computer-readable medium according to claim 1 or 2, wherein, The predicted value is predicted based on statistics of previously received uplink retransmission indices weighted by the modulation and coding scheme (MCS) of the uplink data associated with each uplink retransmission index.

4. The computer-readable medium according to claim 1 or 2, wherein, The predicted value is predicted based on gradient measurements of the uplink transmission power change determined for a previously received uplink transmission power control (TPC) command.

5. The computer-readable medium according to claim 1 or 2, wherein, The predicted value is predicted based on downlink channel quality measurements for a specific downlink reference signal that is spatially associated with the transmitted uplink data.

6. The computer-readable medium according to claim 1 or 2, wherein, The predicted value is predicted based on at least one of the following weighted information: Statistics on previously received uplink retransmission indexes, The gradient information determined for the previously received uplink transmission power control (TPC) command, and Downlink channel quality measurement for a specific downlink reference signal that is spatially associated with transmitted uplink data.

7. The computer-readable medium of claim 1 or 2, further comprising instructions that, in response to being executed by one or more processors, cause the one or more processors to: When the predicted value is below the threshold, the uplink retransmission memory is released, and when the predicted value is above the threshold, the uplink retransmission memory is retained.

8. The computer-readable medium of claim 7, further comprising instructions that, in response to being executed by one or more processors, cause the one or more processors to: The threshold is adjusted based on the Quality of Service (QoS) requirements of higher-level applications.

9. The computer-readable medium of claim 1 or 2, further comprising instructions that, in response to being executed by one or more processors, cause the one or more processors to disable the prediction of the uplink retransmission.

10. A computer-implemented method, comprising: Uplink data is stored in the uplink retransmission memory; and Based on the predicted uplink retransmission value, the uplink retransmission memory is released regardless of whether an uplink retransmission indicator is received from the base station. The uplink retransmission indicator indicates the successful transmission of uplink data stored in the uplink retransmission memory.

11. The computer implementation method according to claim 10, wherein, The predicted value is predicted based on statistics from previously received uplink retransmission indexes.

12. The computer implementation method according to claim 10 or 11, wherein, The predicted value is predicted based on statistics of previously received uplink retransmission indices weighted by the modulation and coding scheme (MCS) of the uplink data associated with each uplink retransmission index.

13. The computer implementation method according to claim 10 or 11, wherein, The predicted value is predicted based on gradient measurements of the uplink transmission power change determined for a previously received uplink transmission power control (TPC) command.

14. The computer implementation method according to claim 10 or 11, wherein, The predicted value is predicted based on downlink channel quality measurements for a specific downlink reference signal that is spatially associated with the transmitted uplink data.

15. The computer implementation method according to claim 10 or 11, wherein, The predicted value is predicted based on at least one of the following weighted information: Statistics on previously received uplink retransmission indexes, The gradient information determined for the previously received uplink transmission power control (TPC) command, and Downlink channel quality measurement for a specific downlink reference signal that is spatially associated with transmitted uplink data.

16. The computer implementation method according to claim 10 or 11, further comprising: When the predicted value is below the threshold, the uplink retransmission memory is released, and when the predicted value is above the threshold, the uplink retransmission memory is retained.

17. The computer implementation method according to claim 16, further comprising: The threshold is adjusted based on the Quality of Service (QoS) requirements of higher-level applications.

18. The computer implementation method according to claim 10 or 11, further comprising: The prediction of uplink retransmission is disabled.

19. A computing system comprising: One or more processors; and A memory that stores instructions that, in response to being executed by the one or more processors, cause the one or more processors to perform the method of any one of claims 10 to 18.

20. A computing device comprising means for performing the method of any one of claims 10 to 18.

21. A computer program product comprising instructions that, in response to being executed on a computing device, cause the computing device to perform the method of any one of claims 10 to 18.

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