WO2023249842A1 - Répétition de paquets intelligente dans des liaisons de service mobile par satellite (mss) pour surmonter des obstructions de canal - Google Patents

Répétition de paquets intelligente dans des liaisons de service mobile par satellite (mss) pour surmonter des obstructions de canal Download PDF

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Publication number
WO2023249842A1
WO2023249842A1 PCT/US2023/025175 US2023025175W WO2023249842A1 WO 2023249842 A1 WO2023249842 A1 WO 2023249842A1 US 2023025175 W US2023025175 W US 2023025175W WO 2023249842 A1 WO2023249842 A1 WO 2023249842A1
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WIPO (PCT)
Prior art keywords
packet
user equipment
repeat
value
base station
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PCT/US2023/025175
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English (en)
Inventor
Santanu Dutta
Dunmiin ZHENG
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Atc Technologies, Llc
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Priority claimed from US17/848,988 external-priority patent/US20220337330A1/en
Application filed by Atc Technologies, Llc filed Critical Atc Technologies, Llc
Publication of WO2023249842A1 publication Critical patent/WO2023249842A1/fr

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B17/00—Monitoring; Testing
    • H04B17/30—Monitoring; Testing of propagation channels
    • H04B17/309—Measuring or estimating channel quality parameters
    • H04B17/347—Path loss
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/08—Arrangements for detecting or preventing errors in the information received by repeating transmission, e.g. Verdan system
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00—Arrangements affording multiple use of the transmission path
    • H04L5/003—Arrangements for allocating sub-channels of the transmission path
    • H04L5/0048—Allocation of pilot signals, i.e. of signals known to the receiver
    • H04L5/005—Allocation of pilot signals, i.e. of signals known to the receiver of common pilots, i.e. pilots destined for multiple users or terminals
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00—Arrangements affording multiple use of the transmission path
    • H04L5/003—Arrangements for allocating sub-channels of the transmission path
    • H04L5/0053—Allocation of signaling, i.e. of overhead other than pilot signals
    • H04L5/0057—Physical resource allocation for CQI
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B17/00—Monitoring; Testing
    • H04B17/30—Monitoring; Testing of propagation channels
    • H04B17/309—Measuring or estimating channel quality parameters
    • H04B17/318—Received signal strength

Definitions

  • Embodiments described herein relate to satellite wireless communications systems and, more particularly, to providing intelligent packet repetition in mobile satellite service (MSS) links to overcome channel blockages.
  • MSS mobile satellite service
  • Satellite communications systems and methods are widely used for communications with user equipment (UE). Satellite communications systems and methods generally employ at least one space-based component, such as one or more satellites, which are configured to wirelessly communicate with UEs on the Earth.
  • space-based component such as one or more satellites
  • the term “UE” includes cellular or satellite radiotelephones with or without a multi-line display; Personal Communications System (PCS) terminals (e.g., user terminals) that may combine a radiotelephone with data processing, data communications capabilities; smart telephones that can include a radio frequency transceiver and/or a global positioning system (GPS) receiver; and/or conventional portable computers or other electronic devices, which devices include a radio frequency transceiver.
  • PCS Personal Communications System
  • the term “transceiver” may refer to a combined transmitter-receiver component or may refer to devices that include separate transmitter and receiver components.
  • a UE also includes any other radiating user device, equipment and/or source that may have time-varying or fixed geographic coordinates and/or may be portable, transportable, installed in a vehicle (aeronautical, maritime, or land-based) and/or situated and/or configured to operate locally and/or in a distributed fashion over one or more terrestrial locations.
  • vehicle aneronautical, maritime, or land-based
  • space-based component or “space-based system” includes one or more satellites at any orbit (geostationary, substantially geostationary, medium earth orbit, low earth orbit, etc.) and/or one or more other objects and/or platforms (e.g., airplanes, balloons, unmanned vehicles, space crafts, missiles, etc.) that has/have a trajectory above the earth at any altitude.
  • Mobile satellite service operates with relatively low link margins compared to terrestrial wireless systems. This is because of the much greater propagation ranges involved in MSS relative to terrestrial w ireless systems.
  • a typical radio frequency propagation scenario for a terrestrial wireless system is illustrated in FIG. 1.
  • a UE 102 is in wireless communication with a transmission tower 104 via one or more non-line-of-sight (NLOS) links 106.
  • NLOS non-line-of-sight
  • LOS line-of-sight
  • terrestrial links are normally of non4ine-of-sight (NLOS) type.
  • NLOS links Radio propagation over NLOS links (e.g., the NLOS links 106) occurs mostly by reflections from environmental clutter, for example, buildings 108, trees (not shown), and the like.
  • Terrestrial wireless links are designed so that, despite the direct path being blocked, enough signal power still reaches the receiver of the UE 102 to close the link from a demodulation perspective. Therefore, useful information can be sent over such links.
  • Link closure occurs despite the presence of substantial, excess attenuation and multipath fading relative to a LOS link.
  • FIG. 2 shows a satellite 202 sending a signal to a vehicle mounted mobile satellite terminal 204 in an urban area 206. Although it is desirable to operate MSS in LOS conditions, this is not always possible when the user equipment is mobile, for example, as shown in FIG. 2. As illustrated in FIG. 2,
  • the signal received by the vehicle mounted mobile satellite terminal 204 may switch between LOS modes (e.g., receiving the signal via the LOS path 208) and NLOS modes (e.g., receiving the signal exclusively via the reflected paths 210) randomly as the line-of- sight path to the satellite 202 is intermittently blocked by buildings 212 and trees 214 as the vehicle moves.
  • the LOS channel also undergoes limited fading due to the environmental multipath, which may be present even when a direct path to the transmitter is also present. This fading is characterized as Rician and has much less depth than the Rayleigh fading present in NLOS channels.
  • MSS propagation literature e.g., Fernando Perez Fontan, et al., “Statistical Modeling of the LMS Channel,” IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY, VOL 50, NO. 6, NOVEMBER 2001 p. 1549
  • Three major states i.e., State 1, State 2, and State 3
  • Chart 302 illustrates a received signal amplitude relative to LOS (in dB) as a function of the traveled distance of the signal (in m).
  • Chart 304 illustrates a probability density function for a received signal as a function of the received signal amplitude relative to LOS (in dB).
  • the propagation mode is LOS.
  • the signal has a mean value relative to a predetermined mean threshold value 306 that is sufficient to close the link with adequate margin (typically less than 4-5 dB) to accommodate the Rician fading. If the UE is of handheld type, up to 10 dB of link margin may be allowed for body absorption and lower antenna directivity of the UE.
  • the direct path to the satellite may be shadowed by tree foliage and subject to knife edge diffraction but no opaque blockage, such as by a building, is present; this is referred to as “shadowing” and results in an incremental pathloss over a clear LOS link of approximately 4dB.
  • the direct path is blocked, leading to typically greater than 15dB additional pathloss, depending on the nature of the building material.
  • Terrestrial wireless systems such as LTE, incorporate a feature known as “Hybrid Automatic Repeat reQuest,” or HARQ.
  • HARQ requires a back-and-forth transaction between the transmitter and the receiver for every repeat.
  • GEO MSS with an approximately 600ms round trip delay
  • implementing HARQ would impose a prohibitive latency and capacity cost.
  • the round-trip delay is only few milliseconds. Therefore, HARQ and other terrestrial system solutions are unable to solve the problems of channel blockages in mobile satellite systems in a practical and cost-effective manner.
  • Sending multiple packet repetitions without an associated ARQ is also used in LTE, but not as part of a dynamic, adaptive scheme, such as the Adaptive Blind Repetition (ABR) system described here.
  • ABR Adaptive Blind Repetition
  • Non-adaptive blind repetition is used in the prior art to statically optimize the link margin for a given UE, especially those in disadvantaged locations. These, blind repetitions, once configured, are static and not adaptive.
  • Embodiments described herein provide, among other things, systems and methods for modifying transmit signals to adaptively repeat transmitted packets based on feedback information about the channel blockage state and combine repeated packets at a receiver. Using such embodiments results in, among other things, an increase in successful demodulation and decoding of the received packets.
  • the system includes a first communications device including a transceiver and an electronic processor.
  • the electronic processor is configured to transmit and receive packetized wireless communications with a second communications device via a bidirectional wireless link.
  • the electronic processor is configured to receive, from the second communications device, feedback information including an indication of a blockage in the communication channel, the indication including information indicating the presence and extent of the blockage, wherein the feedback does not include status indications for individual received packets.
  • the electronic processor is configured to, responsive to receiving the indication of a blockage in the communication channel, determine a packet repeat value based on the feedback information, wherein the packet repeat value may be greater than one.
  • the electronic processor is configured to modify a downlink signal of the bidirectional wireless link to repeat transmitted packets based on the packet repeat value.
  • the electronic processor is configured to control the transceiver to transmit the downlink signal.
  • Another example embodiment discloses a method for intelligent packet repetition.
  • the method includes transmitting and receiving packetized wireless communications between a first communications device and a second communications device via a bidirectional wireless link.
  • the method includes receiving, by the first communications device from the second communications device, feedback information including an indication of a blockage in the communication channel, the indication including information indicating the presence and extent of the blockage, wherein the feedback does not include status indications for individual received packets.
  • the method includes, responsive to receiving the indication of a blockage in the communication channel, determining a packet repeat value based on the feedback information, wherein the packet repeat value may be greater than one.
  • the method includes modifying a downlink signal of the bidirectional wireless link to repeat transmitted packets based on the packet repeat value.
  • the method includes transmitting the downlink signal.
  • the system includes a base station and a user equipment.
  • the base station and the user equipment are configured to transmit and receive wireless communications via a bidirectional wireless link including a downlink signal and an uplink signal.
  • the user equipment is configured to estimate a propagation channel excess pathloss of the downlink signal and encode the excess pathloss to a quantized deficit value by using a single binary digit.
  • the user equipment generates the single binary digit using a process of binary sequential encoding.
  • the user equipment is configured to communicate the quantized deficit value to the base station.
  • the propagation channel excess pathloss corresponds to a plurality of states of the downlink signal.
  • the plurality of states comprises an ordered list from a relatively low excess path loss to a relatively high excess path loss.
  • the plurality of states is restricted to transition between states sequentially according to their order.
  • the user equipment is further configured to estimate the propagation channel excess pathloss for the bidirectional wireless link based on a signal strength received by the user equipment.
  • the base station is further configured to transmit a plurality of narrowband spread spectrum reference signals and the user equipment is further configured to receive the plurality of narrowband spread spectrum reference signals and estimate the signal strength by combining the plurality of narrowband spread spectmm reference signals over multiple symbols.
  • the user equipment combines the plurality of narrowband spread spectrum reference signals over multiple symbols by coherently combining the plurality of narrowband spread spectrum reference signals over frequency-domain elements and time-domain elements.
  • the base station is configured to determine packet repeat values for at least a first and second packet type, based on the quantized deficit value, modify the downlink signal of the bidirectional wireless link to repeat transmitted packets based on their packet repeat values corresponding to their packet types, and transmit the downlink signal using the packet repeat values.
  • the packet repeat values are indicative of the numbers of packet repetitions necessary to enable the user equipment to receive the transmitted packet types with adequate reliability by packet combining.
  • the packet repeat value is not explicitly communicated by the base station to the user equipment before the packet repetition is commenced, whereas for the second packet type, the corresponding repeat value is transmitted to the user equipment before the packet repetition is commenced.
  • the user equipment unilaterally determines an expected packet repeat value for the first packet type without being informed by the base station of the packet repeat value, determines an expected time of arrival at the user equipment of the first packet type, and begins processing a received packet of the first packet type at the expected time of arrival on the assumption that the received packet will be repeated a number of times corresponding to the expected packet repeat value. In some instances, the user equipment determines the expected time of arrival at the user equipment of the first packet ty pe based on a timer, whose period includes an expected round trip propagation delay and an expected base station processing delay.
  • the user equipment is configured to receive from the base station an indication of the packet repeat value to be used on the uplink, modify the uplink signal of the bidirectional wireless link to repeat transmitted packets based on their packet repeat value, and transmit the uplink signal using the packet repeat values.
  • FIG. 1 is a diagram of an RF signal propagation scenario for a terrestrial wireless network.
  • FIG. 2 is a diagram of an RF signal propagation scenario for an MSS wireless network.
  • FIG. 3 is a diagram of some example received signal states for an MSS wireless network.
  • FIG. 4 is a flow chart illustrating a method of packetized wireless communications betw een two nodes according to some embodiments.
  • FIG. 5 is a diagram of a wireless communications system according to some embodiments.
  • FIG. 6 is a chart illustrating aspects of the operation of the system of FIG. 5 according to some embodiments.
  • FIG. 7 is a diagram illustrating a link adaptation method according to some embodiments.
  • FIG. 8 is a process flow diagram illustrating a method enabling a UE to sense and share QDV (Quantized Deficit Value) with an eNB (or LTE base station) according to some embodiments.
  • QDV Quality of Service
  • FIG. 9 is a process flow diagram illustrating a method for the downlink data transmission in the eNB when the ABR approach is used according to some embodiments.
  • FIG. 10 is a process flow diagram illustrating a method for uplink data transmission in the eNB when the ABR approach is used according to some embodiments.
  • FIG. 11 is a chart illustrating example subframe including NRS (Narrowband Reference Signal) Time-Frequency locations according to some embodiments.
  • NRS Nearband Reference Signal
  • control units and “controllers” described in the specification can include one or more processors, one or more memory modules including non-transitory computer-readable medium, one or more input/output interfaces, and various connections (e.g., a system bus) connecting the components.
  • each of the example systems or devices presented herein is illustrated with a single exemplar of each of its component parts. Some examples may not describe or illustrate all components of the systems. Other example embodiments may include more or fewer of each of the illustrated components, may combine some components, or may include additional or alternative components.
  • embodiments provided herein provide systems that, responsive to the detection of channel blockage use adaptive packet repetition at the transmitter and combining of the repeated packets at the receiver to increase the probability' of successful demodulation/decoding of the packet. As set forth herein, packets are repeated only when required and the number of repetitions is dependent on the pathloss created by the blockage.
  • FIG. 4 is a flowchart illustrating a method 400 for intelligent packet repetition.
  • the method 400 may be performed with respect to a bidirectional wireless link between two nodes (e.g., as illustrated in FIG. 5).
  • FIG. 5 schematically illustrates a wireless communications system 500.
  • the wireless communications system 500 includes two nodes, Node A and Node B.
  • Node A and Node B are communications device, which communicate via a bidirectional wireless link 502.
  • Node A and Node B are part of a larger wireless network (e.g., an MSS netw ork).
  • Node A is a satellite or a hub (also referred to as a gateway) of a satellite network and Node B is a UE of the satellite netw ork.
  • Node A includes a baseband processor 504, a transceiver 506, and an antenna 508.
  • the baseband processor 504 includes digital signal processors (DSPs) and other hardware or software suitable to perform the methods described herein.
  • the baseband processor 504 controls the transceiver 506 to transmit and receive voice, video, and other data to and from Node B.
  • the baseband processor 504 encodes and decodes digital data sent and received by the transceiver 506.
  • the transceiver 506 transmits and receives radio signals to and from, for example, Node B using the antenna 508.
  • the baseband processor 504 and the transceiver 506 may include various digital and analog components (e.g., memory and inputoutput (I/O) ports), which for brevity are not described herein and which may be implemented in hardware, software, or a combination of both.
  • Node A includes other hardware and software components not described herein. Some embodiments include separate transmitting and receiving components, for example, a transmitter and a receiver, instead of a combined transceiver 506.
  • Node B includes a baseband processor 510, a transceiver 512, and an antenna 514. The components of Node B are similar to their corresponding components in Node A and are configured to operate in a similar fashion according to embodiments described herein.
  • Embodiments described herein, including the method 400, may be implemented by the baseband processors 504, 510 or by general microprocessors, also referred to as central processing units (CPUs) (not shown), coupled to the baseband processors 504, 510 and other components of Node A and Node B.
  • the system 500 described is but one example. Other implementations (including hardware, software, or combinations thereof) are possible.
  • the inventive concepts set forth herein apply to other implementation approaches.
  • the methods described herein may be applied to both the forward link (FL) (also referred to as the downlink (DL)) and to the retur link (RL) (also referred to as the uplink (UL)).
  • FL forward link
  • RL retur link
  • the term “link” refers to the service link (e.g., the satellite-to-UE link).
  • transmitter may refer to satellite for FL or UE for RL
  • receiver may refer to UE for FL or satellite for RL.
  • the method 400 is descnbed in terms of an MS S use case, where Node A is a satellite and Node B is a UE.
  • the method 400 is described as being performed by the baseband processor 510 of Node B.
  • portions of the method 400 may be performed by other devices, including for example, Node A.
  • the method 400 is described in terms of an MSS including only two nodes.
  • the method 400 may be applied to an MSS including multiple satellites and tens, hundreds, or even thousands of UEs.
  • the method 400 is applicable to other use cases.
  • the baseband processor 510 estimates the mean value of the received signal (referred to herein as the MeanJValue). Note that, in the MSS case, “link” refers to the service link (i.e., the satellite-to-UE link). In some embodiments, the baseband processor 510 determines the Mean_Value by receiving and processing a sounding signal (also referred to as pilot signal), at the transceiver 512.
  • a sounding signal also referred to as pilot signal
  • a Mean_V alue may be determined in both the forward and return links by receiving and processing a sounding signal.
  • the sounding signal is generated and transmitted by a satellite base station subsystem (S-BSS), relayed by the satellite (e.g., Node A of FIG. 5), and received and processed by the UE (e.g., Node B of FIG. 5).
  • the sounding signal is generated and transmitted by the UE (e.g., Node B of FIG. 5), relayed by the satellite (e.g., Node A of FIG. 5) and received/processed by the S-BSS.
  • relaying a signal means receiving the signal, amplifying and frequency shifting the signal, and transmitting the signal at the shifted frequency.
  • the sounding signal be of spread spectrum type, such as a pseudo-noise (PN) signal, so that the signal can be received, and the pathloss measured reliably, even when the power spectral density (PSD) of the received PN signal, S, is well below that of the ambient noise and interference (N+I).
  • PN pseudo-noise
  • the spread spectrum gain of the PN signal enables reliable signal reception with negative S/(N+I) PSD ratios. This provides a large dynamic range for pathloss measurement.
  • the processing of the spread spectrum signal i.e., the operations of signal acquisition and dispreading
  • the baseband processor 512 determines whether the Mean_V alue (determined at block 402) is less than a first threshold value (referred to herein as the Mean_Threshold_Value). For example, the baseband processor 510 compares numerical values for the MeanJValue and the Mean_Threshold_Value. In some embodiments, the Mean_Threshold_Value is set to a fixed, empirically determined value. In other embodiments, the Mean_Threshold_Value may be determined automatically by, for example, using machine learning methods.
  • Node B or another component of the wireless communications system 500 may use various machine learning methods to analyze historical Mean_Value data points stored in a memory and/or a database to make determinations regarding the Mean_Threshold_Value.
  • Machine learning generally refers to the ability of a computer program to leam without being explicitly programmed.
  • a computer program (sometimes referred to as a learning engine) is configured to construct a model (for example, one or more algorithms) based on example inputs.
  • Supervised learning involves presenting a computer program with example inputs and their desired (actual) outputs.
  • the computer program is configured to leam a general rule (a model) that maps the inputs to the outputs in the training data.
  • Machine learning may be performed using various types of methods and mechanisms. Example methods and mechanisms include decision tree learning, association mle learning, artificial neural networks, inductive logic programming, support vector machines, clustering, Bayesian networks, reinforcement learning, representation learning, similarity and metric learning, sparse dictionary learning, and genetic algorithms. Using some or all of these approaches, a computer program may ingest, parse, and understand data and progressively refine models for data analytes, including image analytics. Once trained, the computer system may be referred to as, among other things, an intelligent system, an artificial intelligence (Al) system, a cognitive system, or an intelligent agent.
  • Al artificial intelligence
  • an intelligent agent analyzes the accumulated history of the Mean_Value over some observation time (T obs) for which atypical value might be 15 minutes, and which is informed by the loading of the spotbeam in which the UE is located over a similar observation period.
  • the intelligent agent computes a probability distribution function (PDF) of Mean_Value over T_obs, to produce a chart, such as the chart 304 shown in the inset in FIG. 3. This PDF may be used to determine the Mean Threshold Value.
  • the Mean_Threshold_Value may be chosen by using criteria such as: at any time, the increased load on the network due to packet repetition must not cause the network load to reach more than 70% of the available capacity. Machine Learning may be used to inform the selection of Mean Threshold Value.
  • the baseband processor 510 determines that no packet repetitions are necessary and sets the value of a packet repeat value (N_Repeat) to 1 (representing a single transmission, without repetition).
  • N_Repeat a packet repeat value
  • the value of N_Repeat is used by the baseband processor 510 to control how many times a packet is re-transmitted.
  • the value of N_Repeat is communicated by Node B 510 (the receiver in this example) to Node A 504 (the transmitter in this example).
  • the baseband processor 510 determines aDeficit_Value for the link.
  • the baseband processor 504 determines whether the Deficit_Value (determined at block 408) is less than a second threshold value (referred to herein as the Deficit Threshold Value). For example, the baseband processor 504 compares numerical values for the Deficit Value and the Deficit Threshold Value. If the Deficit Value is less than the Deficit Threshold Value.
  • Deficit_Threshold_Value e.g., a Deficit Threshold Value of 3 dB
  • this threshold provides a hysteresis effect, which improves the operational stability of the system.
  • the Deficit_Threshold_Value is set automatically, for example by using machine learning methods to analyze historical data (including link margin deficit values, related N_Repeat values, and data indicating packet demodulation and decoding success or error rates).
  • the baseband processor 510 returns to block 402 and begins determining and processing another Mean_Value for the link’s pathloss.
  • the Deficit Threshold Value is an upper limit beyond which packet repetitions are unlikely to yield practical benefits, or the capacity tax may be too high.
  • F(Deficit Value) is determined based on the effectiveness of packet repetition and recombination. Methods of combining of repeated packets are known in the prior art. The available options include fully coherent combining and partially coherent/partially incoherent combining. The method chosen has implications for the receiver processor, with fully coherent combining being more challenging to implement but yielding more link margin.
  • the tasks required to sense the presence and depth of blockage and determine N_Repeat as described in FIG. 4, may be differently apportioned between the receiver (Node B) and the transmitter (Node A) than described above.
  • the role of the receiver (Node B) may be limited to sensing a channel quality indicator parameter (CQI), which is indicative of the received SNIR — hence the depth of blockage — and communicating the CQI to the transmitter (Node A).
  • Node A may construct a profile of the received SNIR based on the reported CQI and determine all parameters necessary to execute the flow diagram of FIG.4, including Mean_Value of pathloss and Mean_Threshold_Value.
  • This approach may be preferred in embodiments seeking to maintain affinity to existing standards, as CQI measurement by a receiver and feedback to the transmitter is supported in cellular standards, such as LIE and 5GNR.
  • the receiver performs the Mean_Value estimation, based on signals received on the FL and communicates it back to the transmitter using the RE.
  • the transmitter performs all other functions, including selecting N_Repeat.
  • the receiver performs all functions, including selecting the value of N_Repeat.
  • the N_Repeat value is communicated by the receiver to the transmitter.
  • blockage is defined as a 5-dB loss in the received SNR. This means that the reaction latency would be limited to 12% of the blockage duration. Therefore, the methods of the present invention have the potential to make a material improvement to link closure probability in such environments without levying an excessive capacity tax.
  • Implementation of the proposed adaptive packet repetition method may depend on the various embodiments of the system, which would have different impact on the system performance, operation procedures and control signaling between the receiver and the transmitter.
  • the receiver would make the decision as to how many repetitions were needed based on the measurement of the Mean_Value as described herein.
  • the repetition decision is conveyed to the transmitter through return control channel to take the above repetition action.
  • the transmitter needs to let the receiver know through forw ard control channel where in the time frame, that is, exactly when the repetition begins, so that the receiver can demodulate the received stream correctly.
  • the receiver may set an Update Timer that is equal to the transmission repetition time (TRT) corresponding to the duration over which repetition is made.
  • TRT transmission repetition time
  • the TRT is given by the product of N_Repeat and the duration of the repeated packet of minimum size (the atomic transmitted unit), referred to as Minimum Transmission Block.
  • the receiver will update the N_Repeat value following the procedures described with respect to FIG. 4. Specifically, this means updating the transmitter with information about the next step, i.e., whether or not continue to perform repetition with an updated TRT (corresponding to an updated N_Repeat).
  • FIG. 7 illustrates a graph 700, which includes a link adaption trace 702 according to such an embodiment, assuming the mean received-signal time-variation level profile shown in the top trace. As illustrated in FIG.
  • the above-described embodiments would make transmission repetition adaptive to the channel condition without the need to make a repetition decision after the receipt of every Minimum Transmission Block, unlike HARQ. This is a very' efficient way to achieve near optimal performance in randomly blocked channels, which is absent in the prior art.
  • the embodiment illustrated in FIG. 7 may not work well.
  • Other possible embodiments may be more robust for these types of situations.
  • the receiver may decide to instruct the transmitter to keep doing a blind transmission repetition for a certain period of time regardless of the received signal level to ride out rapidly varying channel conditions.
  • the receiver may set the Update Timer to the period of time duration at the beginning, and by the end of the timer, the receiver would re-evaluate the channel condition, and decide the next step accordingly.
  • the start and end of blind repetitions could be determined by receiver location, or some combination of the above factors. For example, it may be known a priori that certain stretches of a road, or areas of an urban area, are so heavily blocked that it would be best to turn on a certain level of repetition (say 8 repeats of each packet) everywhere in the above locations.
  • wireless communication nodes may be configured to determine a link margin deficit value for an uplink or a downlink.
  • this deficit value is a metric of channel blockage (which is compensated using packet repetitions as described herein).
  • a user equipment (UE) node reports a 3-state channel parameter that corresponds to quantized version of the metric. This channel parameter is referred to as a Quantized Deficit Value (QDV).
  • QDV Quantized Deficit Value
  • a base station node determines the number of narrowband physical downlink control channel (NPDCCH), narrowband physical downlink shared channel (NPDSCH), and narrowband physical uplink shared channel (NPUSCH) repetitions based on look-up tables, while also considering other scheduling requirements.
  • NPDCCH narrowband physical downlink control channel
  • NPDSCH narrowband physical downlink shared channel
  • NPUSCH narrowband physical uplink shared channel
  • the UE communicates the QDV to the eNB using two consecutive bits with binary encoding to represent 3 states of channel blockage (e.g., negligible, medium, and heavy).
  • NPUSCH Format 2 applies to a 1 -bit hybrid automatic repeat request (HARQ) feedback when traditional HARQ is used.
  • HARQ feedback is disabled and the NPUSCH Format 2 is repurposed to apply to a channel state (i.e., QDV) bit.
  • Uplink Control Information (UCI) in narrowband internet of things (NB-IoT) only includes HARQ Feedback - there is no mechanism available for the UE to convey channel quality information such as CSI, LI RSRP, and/or channel blockage states.
  • the methods described in ABR enable channel state feedback through QDV reporting from the UE to the eNB.
  • S2 represents moderate shadowing conditions (Deficit Value > 3 dB).
  • S3 represents deep shadowing conditions (Deficit Value > 12 dB).
  • the channel states will transition sequentially through SI, S2, and S3 (in a Markov sense) and not jump randomly between nonadj acent states.
  • binary sequential encoding may be used to represent the three states by a single bit.
  • the continuous existence of the channel state in the SI (Clear LOS) condition can be represented by a senes of Os and the continuous existence in the S3 (Deep Blockage) state can be represented by a series of Is.
  • the QDV bit will be toggled, the exact value of the bit - 1 or 0 - being immaterial. In this way, the bandwidth efficiency of the QDV channel is the same as that of the HARQ feedback channel.
  • the channel state is estimated by the UE and reported back to the eNB (in this disclosure, ‘eNB’ is used interchangeably with ‘base station’, eNB being the name for base station in 3GPP LTE specifications, which is the context of this disclosure).
  • the eNB makes packet repetition decisions for each UE; this is consistent with the eNB’s present role — the only exception caused by ABR is that an additional factor, channel blockage, informs the number of repetitions.
  • sensing and sharing the channel’s blockage state, between the UE and the eNB is a continuously ongoing background process, occurring independently of the bidirectional packet exchange. In some embodiments, the sensing and sharing of the blockage state occurs periodically.
  • the blockage state information is stored in a Channel State Blockage Database (CSBD) that is rapidly accessible to the eNB, e.g., stored in the local memory.
  • CSBD Channel State Blockage Database
  • the CSBD may be accessed by the eNB to read the most recent QDV, and based on that, make repetition scheduling decisions for both the downlink and uplink. This avoids the expenditure of a roundtrip transaction delay (e.g., to fetch the blockage state information from the UE and then select the number of repetitions) when a DE or UL packet must be scheduled.
  • the eNB thereby has continuous awareness of the channel’s blockage state, except for the 1-hop latency (approximately 300ms) involved in sensing the blockage state by the UE and communicating it to the eNB.
  • FIG. 8 includes a process flow diagram 800 for the background procedure that enables the UE to sense and share QDV with the eNB.
  • the eNB sends an RRCConnectionReconfiguration-NB message to the UE to configure the UE with quiescent ABR parameters along with other typical parameters.
  • quiescent ABR parameters include Mean_Threshold_Value, Deficit_Threshold_Value, periodicity (or frequency) of reporting QDV, and NPUSCH Format 2 resource allocation for the QDV.
  • the UE receives such RRC signaling message at time tS, as illustrated in FIG. 8.
  • the eNB in its normal operation, transmits a Narrowband Reference Signal (‘NRS”) periodically and continually, on specific resource elements in a subframe.
  • NRS Narrowband Reference Signal
  • the UE measures the narrowband reference signal received power (NRSRP) of the NRS with sufficient signal integration time (e.g., 20ms) to achieve a dynamic range of over 20dB in the measurement of channel blockage (the detection of channel blockage through NRSRP by the UE is descnbed below).
  • the UE evaluates the channel blockage condition and sends the QDV bits (coded and formatted as described herein) on the allocated Format 2 NPUSCH
  • FIG. 9 includes a process flow diagram 900 for the downlink data transmission in the eNB when the ABR approach is used. Note that HARQ is assumed to be disabled when ABR is activated. As illustrated in FIG. 9, before allocating radio resources to the UE for the DE, the eNB checks the latest QDV in the CSDB. Informed by QDV and other scheduling considerations, eNB selects a value of TV Repeat NPDSCH X (the number of repetitions for NPDSCH for Packet X) and sends it to the UE in a DCI message on the NPDCCH starting at time t2 and repeating it N Repeat JNPDCCH X times beginning at time t2.
  • TV Repeat NPDSCH X the number of repetitions for NPDSCH for Packet X
  • the NPDCCH specifies N_Repeat for NPDSCH for Packet X (N Repeat NPDSCH X) in DCI Format N1. It should be noted that N_Repeat for the NPDCCH and N_Repeat for the NPDSCH may be different.
  • N repeat NPDCCH The current 3GPP approach to change N repeat for the NPDCCH relies on RRC signaling and is not very dynamic.
  • the UE using an implicit NPDCCH repetition approach, the UE, after sending QDV at a time ta (See FIG. 8), expects to receive the NPDCCH with a new value of N Repeat NPDCCH (corresponding to the last sent QDV) at a time corresponding to: ta+ timer NPDCCH repetitions.
  • the value of timer NPDCCH repetitions includes the RTT and other anticipated delays such as the eNB processing time.
  • the UE will process received NDPCCH packets on the assumption that eNB will transmit NDPCCH packets at the correct time to compensate for the 1-hop time of flight to the targeted UE, so that the packet arrives at the UE at the expected time (within expected error bounds).
  • N Repeat NPDSCH andN_Repeat_PUSCH there is no need for the eNB to distribute N Repeat NPDCCH to the UE before packet repetitions start. This is because both eNB and UE are implicitly aware of N Repeat NPDCCH based on its dependence on QDV, which is known to both the UE and eNB through the process of QDV sharing.
  • N_Repeat is determined by the eNB, not the UE, by considering both QDV and other scheduling factors that are not visible to the UE.
  • this approach retains the central role of the eNB in resource scheduling, which is important in cellular networks.
  • the eNB After specifying the downlink resource allocation on the NPDCCH, the eNB transmits Packet 1 on the NPDSCH using N Repeat NPDSCH l repetitions. The UE receives Packet 1 on the repeated NPDSCH transmissions. It should be understood that ‘Packet 1 ’ does not refer to a single packet but ‘a plurality of packets in the in the first set of packets’ covered by the selected number of repetitions. The same applies to Packet 2.
  • the eNB is again ready to transmit downlink data to the UE at time t3.
  • the eNB checks the latest QDV and, based on the channel blockage state and other considerations, the eNB transmits the UE-specific NPDCCH N_Repeat_2 times beginning at time t4 and, in the NPDCCH packets, specifies the number of NPDSCH repetitions in DCI Format N1 as N_Repeat_NPDSCH_2.
  • the eNB transmits Packet 2 on the NPDSCH using above-specified repetitions.
  • the eNB uses the appropriate number of NPDSCH repetitions whenever it needs to transmit downlink data to the UE.
  • ABR adapts the number of NPDSCH repetitions to the extent of channel blockage.
  • FIG. 10 includes a process flow diagram 1000 for the uplink data transmission in the eNB when the ABR approach is used.
  • the eNB checks the latest QDV in the CSDB before allocating radio resources to the UE. Based on the channel blockage state and other scheduling considerations, the eNB transmits the UE-specific NPDCCH packets
  • the eNB specifies the number of NPUSCH repetitions in DCI Format NO as N Repeat NPUSCH _1.
  • N Repeat NPUSCH _1 As described for the DL data transmission, an implicit NPDCCH repetition approach is proposed.
  • the UE after sending QDV at time ta, expects to receive the NPDCCH with a new value of N Repeat NPDCCH (corresponding to the last sent QDV) at time: ta+timer_NPDCCH_repetitions.
  • the eNB specifies the mapping between QDV and N Repeat NPDCCH, as well as timer_NPDCCH_repetitions via RRC signaling as part of quiescent data distribution.
  • the value of timer NPDCCH repetitions reflects RTT and other delays such as the eNB processing time.
  • the UE After receiving the uplink resource allocation on the NPDCCH, the UE transmits Packet 1 on the NPUSCH using the number of NPUSCH repetitions (N Repeat NPUSCH X) specified by the eNB.
  • the eNB receives Packet 1 on the repeated NPUSCH.
  • the eNB is again ready to allocate uplink resources to the UE at time t3.
  • the eNB checks the latest QDV. Based on the channel blockage state and other considerations, the eNB transmits the UE-specific NPDCCH packets N_Repeat_NPDCCH_2 times beginning at time t4, which specify the number of NPUSCH repetitions (N_Repeat_NPUSCH_2) in DCI Format NO.
  • the UE transmits Packet 2 on the NPUSCH the prescribed number of times.
  • the eNB allocates the uplink radio resources to the UE associated with the appropriate number of NPUSCH repetitions whenever the UE needs uplink resources. Hence, when channel blockage occurs, there is little to no performance loss, because ABR adapts the number of NPUSCH repetitions to the extent of channel blockage.
  • NB-IoT does support a dy namic number of repetitions of the PDSCH and the PUSCH, in that the eNB can specify the PDSCH and PUSCH repetition factors in a DCI.
  • the lack of a suitable feedback channel makes it difficult to make the repetition factors adaptive to dynamic channel blockages.
  • the eNB may configure the NB-IoT UE via RRC signaling with a threshold (which quantifies the excess path loss due to the radio channel blockage) to enable the UE to detect the occurrence and disappearance of radio channel blockage.
  • the eNB may configure the UE via RRC signaling with two separate thresholds to detect (i) occurrence of the radio channel blockage and (ii) disappearance of the radio channel blockage. Because the downlink Narrowband Reference Signal (NRS) transmit power per Resource Element (RE) is constant, the occurrence of channel blockage suddenly reduces the NRS received power at the UE. Hence, the received NRS powder may be used to detect the radio channel blockage.
  • FIG. 11 illustrates an example subframe 1100 including NRS Time-Frequency locations.
  • the RSRP may be calculated by averaging the power of the Reference Signal over all 8 NRS Resource Elements (REs) in a subframe (See FIG. 11).
  • NRSRP Narrowband RSRP
  • robust estimation of Narrowband RSRP (NRSRP) is enabled using integration (i.e., accumulation instead of averaging) of NRS.
  • NRSRP is calculated by integrating the received NRS signals over all 8 NRS REs in each data subframe and then integrating over N multiple data subframes.
  • This process provides the processing gain of 101og(8*N) dB, which ensures sufficient sensitivity and dynamic range of power detection and estimation for low SNR and blockage channel conditions.
  • 17 subframes carry NRS
  • 3 subframes carry NPSS and NSSS.
  • this approach supports more than 21 dB of dynamic range in sensing the channel blockage.
  • processors such as microprocessors, digital signal processors, customized processors and field programmable gate arrays (FPGAs) and unique stored program instructions (including both software and firmware) that control the one or more processors to implement, in conjunction with certain non-processor circuits, some, most, or all of the functions of the systems, methods and/or devices described herein.
  • processors such as microprocessors, digital signal processors, customized processors and field programmable gate arrays (FPGAs) and unique stored program instructions (including both software and firmware) that control the one or more processors to implement, in conjunction with certain non-processor circuits, some, most, or all of the functions of the systems, methods and/or devices described herein.
  • FPGAs field programmable gate arrays
  • unique stored program instructions including both software and firmware
  • an apparatus or system for example, as including an electronic processor or other element configured in a certain manner, for example, to make multiple determinations
  • the claim or claim element should be interpreted as meaning one or more electronic processors (or other element) where any one of the one or more electronic processors (or other element) is configured as claimed, for example, to make any one or more than one of the multiple determinations.
  • an embodiment can be implemented as a computer-readable storage medium having computer readable code stored thereon for programming a computer (for example, comprising a processor) to perform a method as described and claimed herein.
  • Examples of such computer-readable storage mediums include, but are not limited to, a hard disk, a CD-ROM, an optical storage device, a magnetic storage device, a ROM (Read Only Memory ), a PROM (Programmable Read Only Memory), an EPROM (Erasable Programmable Read Only Memory), an EEPROM (Electrically Erasable Programmable Read Only Memory) and a Flash memory.
  • Example 1 is a wireless communications system comprising a base station and a user equipment.
  • the base station and the user equipment are configured to transmit and receive wireless communications via a bidirectional wireless link including a downlink signal and an uplink signal.
  • the user equipment is configured to estimate a propagation channel excess pathloss of the downlink signal.
  • the user equipment is configured to encode the propagation channel excess pathloss to a quantized deficit value by using a single binary digit.
  • the user equipment is configured to communicate the quantized deficit value to the base station.
  • Example 2 may include the subject matter of Example 1 and may further specify that the propagation channel excess pathloss corresponds to a plurality of states of the downlink signal.
  • Example 3 may include the subject matter of Example 2 and may further specify that the plurality of states comprises an ordered list from a relatively low excess path loss to a relatively high excess path loss.
  • Example 4 may include the subject matter of Example 3 and may further specify that the plurality" of states is restricted to transition between states sequentially according to their order.
  • Example 5 may include the subject matter of any of Examples 1-4 and may further specify that the user equipment is further configured to estimate the propagation channel excess pathloss for the bidirectional wireless link based on a signal strength received by the user equipment.
  • Example 6 may include the subject matter of Example 5 and may further specify that the base station is further configured to transmit a plurality of narrowband spread spectrum reference signals.
  • the user equipment is further configured to receive the plurality of narrowband spread spectrum reference signals.
  • the user equipment is further configured to estimate the signal strength by combining the plurality of narrowband spread spectrum reference signals over multiple symbols.
  • Example 7 may include the subject matter of Example 6 and may further specify that the user equipment is further configured to combine the plurality of narrowband spread spectrum reference signals over multiple symbols by coherently combining the plurality" of narrowband spread spectrum reference signals over frequency-domain elements and timedomain elements.
  • Example 8 may include the subject matter of any of Examples 1-7 and may further specify that the user equipment is further configured to generate the single binary digit using a process of binary sequential encoding.
  • Example 9 may include the subject matter of any of Examples 1-8 and may further specify that the base station is further configured to determine packet repeat values for at least a first and second packet type, based on the quantized deficit value. The base station is further configured to modify the downlink signal of the bidirectional wireless link to repeat transmitted packets based on their packet repeat values corresponding to their packet types. The base station is further configured to transmit the downlink signal using the packet repeat values. Example 9 may further specify that the packet repeat values are indicative of the numbers of packet repetitions necessary to enable the user equipment to receive the transmitted packet types with adequate reliability by packet combining.
  • Example 10 may include the subject matter of Example 9 and may further specify that the for the first packet type, the packet repeat value is not explicitly communicated by the base station to the user equipment before the packet repetition is commenced, whereas for the second packet type, the corresponding repeat value is transmitted to the user equipment before the packet repetition is commenced.
  • Example 11 may include the subject matter of Example 10 and may further specify that the user equipment is further configured to unilaterally determine an expected packet repeat value for the first packet type.
  • the user equipment is further configured to determine an expected time of arrival at the user equipment of the first packet type.
  • the user equipment is further configured to begin processing a received packet of the first packet type at the expected time of arrival on the assumption that the received packet will be repeated a number of times corresponding to the expected packet repeat value.
  • Example 12 may include the subject matter of Example 11 and may further specify that the user equipment is further configured to determine the expected time of arrival at the user equipment of the first packet type based on a timer, whose period includes an expected round trip propagation delay and an expected base station processing delay.
  • Example 13 may include the subject matter of any of Examples 1-12 and may further specify that the user equipment is further configured to receive from the base station an indication of the packet repeat value to be used on the uplink. The user equipment is further configured to modify the uplink signal of the bidirectional wireless link to repeat transmitted packets based on their packet repeat value. The user equipment is further configured to transmit the uplink signal using the packet repeat values.
  • Example 14 is a method for operating a wireless communications system including a base station and a user equipment configured to transmit and receive wireless communications via a bidirectional wireless link including a downlink signal and an uplink signal. The method includes estimating a propagation channel excess pathloss of the downlink signal. The method includes encoding the propagation channel excess pathloss to a quantized deficit value by using a single binary digit. The method includes communicating the quantized deficit value from the user equipment to the base station.
  • Example 15 may include the subject matter of Example 14 and may further specify that the propagation channel excess pathloss corresponds to a plurality of states of the downlink signal.
  • Example 16 may include the subject matter of Example 15 and may further specify that the plurality of states comprises an ordered list from a relatively low excess path loss to a relatively high excess path loss.
  • Example 17 may include the subject matter of Example 16 and may further specify that the plurality of states is restricted to transition between states sequentially according to their order.
  • Example 18 may include the subject matter of any of Examples 14-17 and may further include estimating the propagation channel excess pathloss for the bidirectional wireless link based on a signal strength received by the user equipment.
  • Example 19 may include the subject matter of Example 18 and may further include receiving, by the user equipment, a plurality of narrowband spread spectrum reference signals.
  • Example 19 may further include estimating the signal strength by combining the plurality of narrowband spread spectrum reference signals over multiple symbols.
  • Example 20 may include the subject matter of Example 19 and may further specify that combining the plurality of narrowband spread spectrum reference signals over multiple symbols includes coherently combining the plurality of narrowband spread spectrum reference signals over frequency-domain elements and time-domain elements.
  • Example 21 may include the subject matter of any of Examples 14-20 and may further specify that generating the single binary' digit includes generating the single binary digit using a process of binary sequential encoding.
  • Example 22 may include the subject matter of any of Examples 14-21 and may further include determining packet repeat values for at least a first and second packet type, based on the quantized deficit value.
  • Example 22 may further include modifying the downlink signal of the bidirectional wireless link to repeat transmitted packets based on their packet repeat values corresponding to their packet types.
  • Example 22 may further include transmitting the downlink signal using the packet repeat values.
  • Example 22 may further specify that the packet repeat values are indicative of the numbers of packet repetitions necessary to enable the user equipment to receive the transmitted packet types with adequate reliability by packet combining.
  • Example 23 may include the subject matter of Example 22 and may further specify that for the first packet type, the packet repeat value is not explicitly communicated by the base station to the user equipment before the packet repetition is commenced, whereas for the second packet type, the corresponding repeat value is transmitted to the user equipment before the packet repetition is commenced.
  • Example 24 may include the subject matter of Example 23 and may further include unilaterally determining, with the user equipment, an expected packet repeat value for the first packet type.
  • Example 24 may further include determining an expected time of arrival at the user equipment of the first packet type.
  • Example 24 may further include beginning processing of a received packet of the first packet type at the expected time of arrival on the assumption that the received packet will be repeated a number of times corresponding to the expected packet repeat value.
  • Example 25 may include the subject matter of Example 24 and may further specify that determining the expected time of arrival at the user equipment of the first packet type is based on a timer, whose period includes an expected round trip propagation delay and an expected base station processing delay.
  • Example 26 may include the subject matter of any of Examples 14-25 and may further include receiving from the base station an indication of the packet repeat value to be used on the uplink.
  • Example 26 may further include modifying the uplink signal of the bidirectional wireless link to repeat transmitted packets based on their packet repeat value.
  • Example 26 may further include transmitting the uplink signal using the packet repeat values.
  • Example 27 includes one or more non-transitory computer readable media having instructions thereon that, when executed by one or more electronic processors, cause the one or more electronic processors to perform the subject matter of any one or more of Examples 14-26.
  • Example 28 includes one or more electronic processors configured to perform the subject matter of any one or more of Examples 14-26.

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Abstract

Systèmes et procédés de répétition de paquets intelligente dans des liaisons de service mobile par satellite pour surmonter des obstructions de canal. Un exemple comprend un système de communication comprenant une station de base et un équipement utilisateur. La station de base et l'équipement utilisateur sont configurés pour émettre et recevoir des communications sans fil par l'intermédiaire d'une liaison sans fil bidirectionnelle comprenant un signal de liaison descendante et un signal de liaison montante. L'équipement utilisateur est configuré pour estimer une perte de trajet en excès de canal de propagation du signal de liaison descendante. L'équipement utilisateur est configuré pour coder la perte de trajet en excès de canal de propagation selon une valeur de déficit quantifiée à l'aide d'un seul chiffre binaire. L'équipement utilisateur est configuré pour communiquer la valeur de déficit quantifiée à la station de base.
PCT/US2023/025175 2022-06-24 2023-06-13 Répétition de paquets intelligente dans des liaisons de service mobile par satellite (mss) pour surmonter des obstructions de canal WO2023249842A1 (fr)

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US17/848,988 US20220337330A1 (en) 2020-03-25 2022-06-24 Intelligent packet repetition in mobile satellite service (mss) links to overcome channel blockages

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6975673B1 (en) * 1998-07-14 2005-12-13 Axonn, L.L.C. Narrow-band interference rejecting spread spectrum radio system and method
US7035632B2 (en) * 2000-09-26 2006-04-25 Scoreboard, Inc. Path loss data normalization for growth management of a cellular system
EP2557830B1 (fr) * 2011-08-11 2014-07-09 Deutsche Telekom AG Procédé de prédiction de rendement MIMO de liaison descendante LTE dans un outil de planification de réseau radio
US20210184809A1 (en) * 2019-12-13 2021-06-17 Qualcomm Incorporated Downlink control information based beam and pathloss reference signal configuration activation
US20210306115A1 (en) * 2020-03-25 2021-09-30 Atc Technologies Llc Intelligent packet repetition in mobile satellite service (mss) links to overcome channel blockages

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6975673B1 (en) * 1998-07-14 2005-12-13 Axonn, L.L.C. Narrow-band interference rejecting spread spectrum radio system and method
US7035632B2 (en) * 2000-09-26 2006-04-25 Scoreboard, Inc. Path loss data normalization for growth management of a cellular system
EP2557830B1 (fr) * 2011-08-11 2014-07-09 Deutsche Telekom AG Procédé de prédiction de rendement MIMO de liaison descendante LTE dans un outil de planification de réseau radio
US20210184809A1 (en) * 2019-12-13 2021-06-17 Qualcomm Incorporated Downlink control information based beam and pathloss reference signal configuration activation
US20210306115A1 (en) * 2020-03-25 2021-09-30 Atc Technologies Llc Intelligent packet repetition in mobile satellite service (mss) links to overcome channel blockages

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