WO2022220812A1

WO2022220812A1 - Apparatus and method of modified discontinuous reception

Info

Publication number: WO2022220812A1
Application number: PCT/US2021/027132
Authority: WO
Inventors: Yuanye WANG
Original assignee: Zeku, Inc.
Priority date: 2021-04-13
Filing date: 2021-04-13
Publication date: 2022-10-20

Abstract

According to one aspect of the present disclosure, an apparatus for wireless communication is disclosed. The apparatus may include a discontinuous reception (DRX) module. The DRX module may include a mode determination unit configured to determine whether to enter a modified DRX mode based on at least one threshold condition. The modified DRX mode may include monitoring a subset of paging occasions used by a serving base station. The DRX module may further include a modified DRX mode unit configured to operate using the modified DRX mode when the at least one threshold condition is met. The DRX module may further include a monitoring unit configured to monitor the subset of paging occasions while in the modified DRX mode.

Description

APPARATUS AND METHOD OF MODIFIED DISCONTINUOUS

RECEPTION

BACKGROUND

[0001] Embodiments of the present disclosure relate to apparatus and method for wireless communication.

[0002] Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. In cellular communication, such as the 4th-generation (4G) Long Term Evolution (LTE) and the 5th- generation (5G) New Radio (NR), the 3rd Generation Partnership Project (3GPP) defines various mechanisms for conserving battery power at the user equipment (UE), e.g., such as discontinuous reception (DRX).

SUMMARY

[0003] Embodiments of apparatus and method for DRX mode selection are disclosed herein. [0004] According to one aspect of the present disclosure, a first apparatus for wireless communication of a UE is disclosed. The apparatus may include a DRX module. The DRX module may include a mode determination unit configured to determine whether to enter a modified DRX mode based on at least one threshold condition. The modified DRX mode may include monitoring a subset of paging occasions used by a serving base station. The DRX module may further include a modified DRX mode unit configured to operate using the modified DRX mode when the at least one threshold condition is met. The DRX module may further include a monitoring unit configured to monitor the subset of paging occasions while in the modified DRX mode.

[0005] According to another aspect of the present disclosure, a second apparatus for wireless communication of a TIE is disclosed. The apparatus may include a memory and at least one processor coupled to the memory. The at least one processor may be configured to determine whether to enter a modified DRX mode based on at least one threshold condition. The modified DRX mode may include monitoring a subset of paging occasions used by a serving base station. The at least one processor may be further configured to enter the modified DRX mode when the at least one threshold condition is met. The at least one processor may be further configured to monitor the subset of paging occasions while in the modified DRX mode.

[0006] According to another aspect of the present disclosure, a method for wireless communication of a UE is disclosed. The method may include determining whether to enter a modified DRX mode based on at least one threshold condition. The modified DRX mode may include monitoring a subset of paging occasions used by a serving base station. The method may further include entering the modified DRX mode when the at least one threshold condition is met. The method may further include monitoring the subset of paging occasions while in the modified DRX mode.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate embodiments of the present disclosure and, together with the description, further serve to explain the principles of the present disclosure and to enable a person skilled in the pertinent art to make and use the present disclosure.

[0008] FIG. 1 illustrates an exemplary wireless network, according to some embodiments of the present disclosure.

[0009] FIG. 2A illustrates a block diagram of an apparatus including a baseband chip, a radio frequency (RF) chip, and a host chip, according to some embodiments of the present disclosure.

[0010] FIG. 2B illustrates a block diagram of an exemplary DRX unit of the baseband chip of FIG. 2A, according to some embodiments of the present disclosure.

[0011] FIG. 3 A illustrates a first timing diagram of regular DRX mode that may be used by the exemplary DRX unit of FIG. 2B, according to some embodiments of the present disclosure. [0012] FIG. 3B illustrates a second timing diagram of modified DRX mode that may be implemented by the exemplary DRX unit of FIG. 2B, according to some embodiments of the present disclosure.

[0013] FIG. 4 illustrates a flow chart of an exemplary method of wireless communication of an apparatus, according to some embodiments of the present disclosure.

[0014] FIG. 5 illustrates a block diagram of an exemplary node, according to some embodiments of the present disclosure.

[0015] Embodiments of the present disclosure will be described with reference to the accompanying drawings.

DETAILED DESCRIPTION

[0016] Although specific configurations and arrangements are discussed, it should be understood that this is done for illustrative purposes only. A person skilled in the pertinent art will recognize that other configurations and arrangements can be used without departing from the spirit and scope of the present disclosure. It will be apparent to a person skilled in the pertinent art that the present disclosure can also be employed in a variety of other applications.

[0017] It is noted that references in the specification to “one embodiment,” “an embodiment,” “an example embodiment,” “some embodiments,” “certain embodiments,” etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it would be within the knowledge of a person skilled in the pertinent art to effect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

[0018] In general, terminology may be understood at least in part from usage in context.

For example, the term “one or more” as used herein, depending at least in part upon context, may be used to describe any feature, structure, or characteristic in a singular sense or may be used to describe combinations of features, structures or characteristics in a plural sense. Similarly, terms, such as “a,” “an,” or “the,” again, may be understood to convey a singular usage or to convey a plural usage, depending at least in part upon context. In addition, the term “based on” may be understood as not necessarily intended to convey an exclusive set of factors and may, instead, allow for existence of additional factors not necessarily expressly described, again, depending at least in part on context.

[0019] Various aspects of wireless communication systems will now be described with reference to various apparatus and methods. These apparatus and methods will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, modules, units, components, circuits, steps, operations, processes, algorithms, etc. (collectively referred to as “elements”). These elements may be implemented using electronic hardware, firmware, computer software, or any combination thereof. Whether such elements are implemented as hardware, firmware, or software depends upon the particular application and design constraints imposed on the overall system.

[0020] The techniques described herein may be used for various wireless communication networks, such as code division multiple access (CDMA) system, time division multiple access (TDMA) system, frequency division multiple access (FDMA) system, orthogonal frequency division multiple access (OFDMA) system, single-carrier frequency division multiple access (SC- FDMA) system, wireless local area network (WLAN) system, and other networks. The terms “network” and “system” are often used interchangeably. A CDMA network may implement a radio access technology (RAT), such as Universal Terrestrial Radio Access (UTRA), evolved UTRA (E-UTRA), CDMA 2000, etc. A TDMA network may implement a RAT, such as the Global System for Mobile Communications (GSM). An OFDMA network may implement a RAT, such as LTE or NR. A WLAN system may implement a RAT, such as Wi-Fi. The techniques described herein may be used for the wireless networks and RATs mentioned above, as well as other wireless networks and RATs.

[0021] An important consideration relating to wireless communication relates to the power consumption of a UE, which often uses a battery as an onboard power source. While improvements in battery technology have assisted in prolonging the operational period before a battery recharge is required, control aspects have also been introduced into the operation of the UE to enhance the efficiency and improve performance. It is commonly provided for the UE to switch between active and idle states, and it is also known that, while the UE is operating in an active state, further control measures such as DRX may be employed to increase performance and reduce power consumption. A base station may instruct a UE to enter DRX mode when continuously monitoring all possible paging channels is unnecessary due to a limited number of downlink data packets for the UE. While in DRX mode, a UE may monitor paging occasions intermittently, as shown in the timing diagram 300 of FIG. 3A.

[0022] FIG. 3A illustrates ten paging occasions 302 each separated by a DRX cycle 304.

The DRX cycle 304 may be a time period in which the UE enters a sleep mode or low-power mode to conserve battery power. Each DRX cycle 304 may be, e.g., 1.28 seconds in length. When the downlink data or an incoming phone call arrive at the base station, a paging transmission may be sent to the UE in one or more consecutive paging occasions to indicate the incoming data. Paging occasions 302 may be the duration between DRX cycles 304 when the UE wakes up to see if the base station has information that needs to be sent to the UE. [0023] In certain situations, the base station may repeat the same paging transmission in two or more consecutive paging occasions to increase the probability of proper decoding. This may be especially true when the base station services a large coverage area. Here, UEs near the edge of the cell may experience a reduced channel quality as compared to UEs closer to the base station. Thus, if the paging transmission cannot be decoded on the first attempt, the UE may reenter low-power mode to await the subsequent paging occasion 302 and attempt to decode the paging transmission a second time. An example of the same paging transmission being sent in consecutive paging occasions is illustrated in FIG. 3A, which depicts a timing diagram 300 of a UE operating in regular DRX mode. In the example illustrated in FIG. 3 A, a first paging transmission is sent by the base station in paging occasions 2 and 3, and a different paging transmission is sent in paging occasions 8 and 9.

[0024] While sending the same paging transmission in two or more paging occasions may benefit UEs experiencing low channel quality, this type of paging transmission pattern may degrade the performance of UEs that are able to reliably decode paging transmissions on the first attempt. This is because UEs nearer to the center of the cell may not need to be in an active state to receive a redundant paging transmission when the paging transmission sent in the previous paging occasion 302 was properly decoded. Thus, in certain situations, regular DRX mode may degrade the performance of a UE by consuming battery power unnecessarily.

[0025] Hence, there is an unmet need for a modified DRX mode that enables a UE to monitor a reduced number of consecutive paging occasions under certain conditions.

[0026] To reduce power consumption, and hence, improve the overall performance of a

UE, the present disclosure enables a UE to operate in a modified DRX mode in which a UE is not required to enter an active state at each paging occasion. Modified DRX mode may be triggered at the UE when at least one threshold condition is met. In one example, the threshold condition may relate to the paging transmission pattern. Under this threshold condition, when the UE determines that the paging transmission pattern of the serving base station or service area (also referred to herein as “tracking area”) includes two or more consecutive paging occasions that contain the same paging transmission, the UE may enter a modified DRX mode such that only a subset of paging occasions are monitored, e.g., as depicted in FIG. 3B. In another example, the threshold condition may relate to channel quality. Under this threshold condition, when the UE determines that the channel quality meets a threshold level, the UE may enter modified DRX mode such that only a subset of paging occasions are monitored. In either example, the subset of paging occasions may be selected such that the tradeoff between power savings and the probability of correctly decoding all paging transmissions is optimized. A UE that implements modified DRX mode may realize a significant reduction in power consumption, as compared with regular DRX mode. Additional details describing the present modified DRX mode are set forth below in connection with FIGs. 1-5.

[0027] FIG. 1 illustrates an exemplary wireless network 100, in which some aspects of the present disclosure may be implemented, according to some embodiments of the present disclosure. As shown in FIG. 1, wireless network 100 may include a network of nodes, such as a UE 102, an access node 104, and a core network element 106. UE 102 may be any terminal device, such as a mobile phone, a desktop computer, a laptop computer, a tablet, a vehicle computer, a gaming console, a printer, a positioning device, a wearable electronic device, a smart sensor, or any other device capable of receiving, processing, and transmitting information, such as any member of a vehicle to everything (V2X) network, a cluster network, a smart grid node, or an Internet-of-Things (IoT) node. It is understood that user equipment 102 is illustrated as a mobile phone simply by way of illustration and not by way of limitation.

[0028] Access node 104 may be a device that communicates with user equipment 102, such as a wireless access point, a base station (BS), a Node B, an enhanced Node B (eNodeB or eNB), a next-generation NodeB (gNodeB or gNB), a cluster master node, or the like. Access node 104 may have a wired connection to user equipment 102, a wireless connection to user equipment 102, or any combination thereof. Access node 104 may be connected to user equipment 102 by multiple connections, and user equipment 102 may be connected to other access nodes in addition to access node 104. Access node 104 may also be connected to other user equipments. It is understood that access node 104 is illustrated by a radio tower by way of illustration and not by way of limitation. [0029] Core network element 106 may serve access node 104 and user equipment 102 to provide core network services. Examples of core network element 106 may include a home subscriber server (HSS), a mobility management entity (MME), a serving gateway (SGW), or a packet data network gateway (PGW). These are examples of core network elements of an evolved packet core (EPC) system, which is a core network for the LTE system. Other core network elements may be used in LTE and in other communication systems. In some embodiments, core network element 106 includes an access and mobility management function (AMF) device, a session management function (SMF) device, or a user plane function (UPF) device, of a core network for the NR system. It is understood that core network element 106 is shown as a set of rack-mounted servers by way of illustration and not by way of limitation.

[0030] Core network element 106 may connect with a large network, such as the Internet

108, or another Internet Protocol (IP) network, to communicate packet data over any distance. In this way, data from user equipment 102 may be communicated to other user equipments connected to other access points, including, for example, a computer 110 connected to Internet 108, for example, using a wired connection or a wireless connection, or to a tablet 112 wirelessly connected to Internet 108 via a router 114. Thus, computer 110 and tablet 112 provide additional examples of possible user equipments, and router 114 provides an example of another possible access node. [0031] A generic example of a rack-mounted server is provided as an illustration of core network element 106. However, there may be multiple elements in the core network including database servers, such as a database 116, and security and authentication servers, such as an authentication server 118. Database 116 may, for example, manage data related to user subscription to network services. A home location register (HLR) is an example of a standardized database of subscriber information for a cellular network. Likewise, authentication server 118 may handle authentication of users, sessions, and so on. In the NR system, an authentication server function (AUSF) device may be the specific entity to perform user equipment authentication. In some embodiments, a single server rack may handle multiple such functions, such that the connections between core network element 106, authentication server 118, and database 116, may be local connections within a single rack.

[0032] Each element in FIG. 1 may be considered a node of wireless network 100. More detail regarding the possible implementation of a node is provided by way of example in the description of a node 500 in FIG. 5. Node 500 may be configured as user equipment 102, access node 104, or core network element 106 in FIG. 1. Similarly, node 500 may also be configured as computer 110, router 114, tablet 112, database 116, or authentication server 118 in FIG. 1. As shown in FIG. 5, node 500 may include a processor 502, a memory 504, and a transceiver 506. These components are shown as connected to one another by a bus, but other connection types are also permitted. When node 500 is user equipment 102, additional components may also be included, such as a user interface (UI), sensors, and the like. Similarly, node 500 may be implemented as a blade in a server system when node 500 is configured as core network element 106. Other implementations are also possible.

[0033] Transceiver 506 may include any suitable device for sending and/or receiving data.

Node 500 may include one or more transceivers, although only one transceiver 506 is shown for simplicity of illustration. An antenna 508 is shown as a possible communication mechanism for node 500. Multiple antennas and/or arrays of antennas may be utilized for receiving multiple spatially multiplex data streams. Additionally, examples of node 500 may communicate using wired techniques rather than (or in addition to) wireless techniques. For example, access node 104 may communicate wirelessly to user equipment 102 and may communicate by a wired connection (for example, by optical or coaxial cable) to core network element 106. Other communication hardware, such as a network interface card (NIC), may be included as well.

[0034] As shown in FIG. 5, node 500 may include processor 502. Although only one processor is shown, it is understood that multiple processors can be included. Processor 502 may include microprocessors, microcontroller units (MCUs), digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functions described throughout the present disclosure. Processor 502 may be a hardware device having one or more processing cores. Processor 502 may execute software. Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise. Software can include computer instructions written in an interpreted language, a compiled language, or machine code. Other techniques for instructing hardware are also permitted under the broad category of software. [0035] As shown in FIG. 5, node 500 may also include memory 504. Although only one memory is shown, it is understood that multiple memories can be included. Memory 504 can broadly include both memory and storage. For example, memory 504 may include random-access memory (RAM), read-only memory (ROM), static RAM (SRAM), dynamic RAM (DRAM), ferro electric RAM (FRAM), electrically erasable programmable ROM (EEPROM), compact disc read only memory (CD-ROM) or other optical disk storage, hard disk drive (HDD), such as magnetic disk storage or other magnetic storage devices, Flash drive, solid-state drive (SSD), or any other medium that can be used to carry or store desired program code in the form of instructions that can be accessed and executed by processor 502. Broadly, memory 504 may be embodied by any computer-readable medium, such as a non-transitory computer-readable medium.

[0036] Processor 502, memory 504, and transceiver 506 may be implemented in various forms in node 500 for performing wireless communication functions. In some embodiments, processor 502, memory 504, and transceiver 506 of node 500 are implemented (e.g., integrated) on one or more system-on-chips (SoCs). In one example, processor 502 and memory 504 may be integrated on an application processor (AP) SoC (sometimes known as a “host,” referred to herein as a “host chip”) that handles application processing in an operating system (OS) environment, including generating raw data to be transmitted. In another example, processor 502 and memory 504 may be integrated on a baseband processor (BP) SoC (sometimes known as a “modem,” referred to herein as a “baseband chip”) that converts the raw data, e.g., from the host chip, to signals that can be used to modulate the carrier frequency for transmission, and vice versa, which can run a real-time operating system (RTOS). In still another example, processor 502 and transceiver 506 (and memory 504 in some cases) may be integrated on an RF SoC (sometimes known as a “transceiver,” referred to herein as an “RF chip”) that transmits and receives RF signals with antenna 508. It is understood that in some examples, some or all of the host chip, baseband chip, and RF chip may be integrated as a single SoC. For example, a baseband chip and an RF chip may be integrated into a single SoC that manages all the radio functions for cellular communication.

[0037] Referring back to FIG. 1, in some embodiments, user equipment 102 may be configured to operate in regular DRX mode or modified DRX mode depending on certain threshold conditions, as described below in detail. As a result, compared with known solutions, the power consumption of the UE 102 described herein, which can operate in modified DRX mode to monitor a subset of paging occasions under certain conditions, may be reduced by at least 10%.

[0038] FIG. 2A illustrates a block diagram of an apparatus 200 including a baseband chip

202, an RF chip 204, and a host chip 206, according to some embodiments of the present disclosure. Apparatus 200 may be an example of any suitable node of wireless network 100 in FIG. 1, such as user equipment 102 or access node 104. As shown in FIG. 2, apparatus 200 may include baseband chip 202, RF chip 204, host chip 206, and one or more antennas 210. In some embodiments, baseband chip 202 is implemented by processor 502 and memory 504, and RF chip 204 is implemented by processor 502, memory 504, and transceiver 506, as described above with respect to FIG. 5. Besides the on-chip memory 218 (also known as “internal memory,” e.g., registers, buffers, or caches) on each chip 202, 204, or 206, apparatus 200 may further include an external memory 208 (e.g., the system memory or main memory) that can be shared by each chip 202, 204, or 206 through the system/main bus. Although baseband chip 202 is illustrated as a standalone SoC in FIG. 2A, it is understood that in one example, baseband chip 202 and RF chip 204 may be integrated as one SoC; in another example, baseband chip 202 and host chip 206 may be integrated as one SoC; in still another example, baseband chip 202, RF chip 204, and host chip 206 may be integrated as one SoC, as described above.

[0039] In the uplink, host chip 206 may generate raw data and send it to baseband chip 202 for encoding, modulation, and mapping. Interface 214 of baseband chip 202 may receive the data from host chip 206. Baseband chip 202 may also access the raw data generated by host chip 206 and stored in external memory 208, for example, using the direct memory access (DMA). Baseband chip 202 may first encode (e.g., by source coding and/or channel coding) the raw data and modulate the coded data using any suitable modulation techniques, such as multi-phase shift keying (MPSK) modulation or quadrature amplitude modulation (QAM). Baseband chip 202 may perform any other functions, such as symbol or layer mapping, to convert the raw data into a signal that can be used to modulate the carrier frequency for transmission. In the uplink, baseband chip 202 may send the modulated signal to RF chip 204 via interface 214. RF chip 204, through the transmitter, may convert the modulated signal in the digital form into analog signals, i.e., RF signals, and perform any suitable front-end RF functions, such as filtering, digital pre-distortion, up-conversion, or sample-rate conversion. Antenna 210 (e.g., an antenna array) may transmit the RF signals provided by the transmitter of RF chip 204.

[0040] In the downlink, antenna 210 may receive RF signals that may include, among other things, a paging transmission sent in a paging occasion and/or a repeating paging transmission received in consecutive paging occasions, which may be used by baseband chip 202 to determine whether there is incoming downlink data and/or voice call. The RF signals may be passed to the receiver (Rx) of RF chip 204. RF chip 204 may perform any suitable front-end RF functions, such as filtering, IQ imbalance compensation, down-paging conversion, or sample-rate conversion, and convert the RF signals (e.g., transmission) into low-frequency digital signals (baseband signals) that can be processed by baseband chip 202.

[0041] In the downlink, interface 214 of baseband chip 202 may receive the RF signals, which are passed to DRX module 216. DRX module 216 may be configured to operate in regular DRX mode or modified DRX mode depending on certain threshold conditions. Non-limiting examples of these threshold conditions may include, e.g., the number of consecutive page occasions used by a base station to send repeated paging transmissions (referred to herein as “paging transmission pattern”), channel quality, among other things. To select the type of DRX mode in which to operate, DRX module 216 may include various units as illustrated in FIG. 2B. Additionally, baseband chip 202 may perform other functions, such as demodulation, decoding, error checking, de-mapping, channel estimation, descrambling, etc. The raw data (e.g., paging transmission, paging transmission pattern information, etc.) provided by baseband chip 202 may be sent to host chip 206 directly via interface 214 or stored in external memory 208.

[0042] When apparatus 200 operates in regular DRX mode, RF chip 204 and baseband chip 202 may exit a sleep mode/low-power mode at each paging occasion as depicted in FIG. 3 A to monitor for a paging transmission. Otherwise, when apparatus 200 operates in modified DRX mode, RF chip 204 and baseband chip 202 may monitor only a subset of paging occasions as depicted in FIG. 3B.

[0043] FIG. 2B illustrates a detailed block diagram of DRX module 216 of FIG. 2 A, according to some embodiments of the disclosure. FIG. 3B illustrates a timing diagram 350 that may be used by a UE operating in modified DRX mode, according to some embodiments of the disclosure. FIGs. 2B and 3B will be described together.

[0044] As illustrated in FIG. 2B, DRX module 216 may include, e.g., a mode determination unit 230, a regular DRX mode unit 232, a modified DRX mode unit 234, a monitoring unit 236, a paging transmission pattern unit 238, a selection unit 240, a database unit 242, a measurement unit 244, and a probability unit 246, just to name a few.

[0045] Once the serving base station has instructed the apparatus 200 to communicate using DRX, mode determination unit 230 may determine whether to operate using regular DRX mode or modified DRX mode. While in regular DRX mode, apparatus 200 may be configured to wake up at each paging occasion 302, as illustrated in FIG. 3A. On the other hand, while in modified DRX mode, apparatus 200 may be configured to monitor a subset of the paging occasions, as illustrated in FIG. 3B. A subset of paging occasions may include, e.g., every other paging occasion (as illustrated in FIG. 3B), every third paging occasion, every fourth paging occasion, etc. Mode determination unit 230 may be configured to determine whether to operate using regular DRX mode or modified DRX mode based at least in part on certain threshold conditions. These threshold conditions may include, e.g., the number of consecutive paging occasions that include the same paging transmission (e.g., paging transmission pattern), the channel quality, and/or the probability of properly decoding a paging transmission after x attempts. Information associated with the paging transmission pattern, channel quality, and/or decoding probability may be obtained and/or identified using one or more of the other units of DRX module 216 and provided to mode determination unit 230. Mode determination unit 230 may use this information, among other things, to select regular DRX mode or modified DRX mode.

[0046] Paging transmission pattern unit 238 may determine the paging transmission pattern used by the serving base station. As mentioned above, a paging transmission pattern may be defined as the number of consecutive paging occasions used by the serving base station and/or tracking area (e.g., group of cells) to transmit a repeating paging transmission. As also mentioned above, when the cell covers a large service area, the base station may use two or more consecutive paging occasions to repeat the transmission of the same paging occasion to increase the probability that the paging transmission is properly decoded. The paging transmission pattern may be determined in various ways, as described below. Each time the UE connects to a particular serving cell and/or tracking area, monitoring unit 236 may monitor paging occasions in regular DRX mode and send information associated with the number of consecutive paging occasions used for repeat transmissions to paging transmission pattern unit 238. From the information received from monitoring unit 236, paging transmission pattern unit 238 may determine the number of consecutive paging occasions used by the base station and/or tracking area, and hence, the paging transmission pattern.

[0047] When it is unlikely that the number of consecutive paging occasions will change while the UE is connected to the network, paging transmission pattern unit 238 may send the number of instantaneous consecutive paging occasions (e.g., n) to mode determination unit. Otherwise, when there is a possibility that the number of consecutive paging occasions may change while the UE is connected to the network, paging transmission pattern unit 238 may access database unit 242 to obtain previous data associated with a previous average number of consecutive paging occasions (e.g., N_previous). Then, a new moving average (e.g., Nnew) of the number of consecutive paging occasions used by the base station and/or tracking for repeat paging transmissions may be computed as shown below in Equation (1):

Nnew ^— (1-a) * Nprevious + (X * n (1), where a may be a scaling factor between 0 and 1 that weights newer consecutive paging occasion data more heavily.

[0048] Equation (1) is only one example of the possible ways to update the paging count.

It can be generalized to Nnew = f(N_previous, n, ... args), where “Nprevious” and “n” are same as defined above; “...args” means any arbitrary number of arguments to be further considered; “f’ may be the process to update the paging count “Nnew” based on all the inputs. It can be a linear transformation function similar as in Equation (1), or can be a non-linear transformation function taking a more complicated shape, or a table lookup process without departing from the disclosure herein.

[0049] Depending on the implementation, the value(s) of Nnew and/or n may be sent to mode determination unit 230, which may compare Nnew and/or n with the associated threshold number to select regular DRX mode or modified DRX mode. Moreover, the value(s) of Nnew and n may be sent to update database unit 242 with the most recent paging transmission pattern information. In one example implementation, the number of consecutive paging occasions (e.g., Nnew or n) may be the sole condition used in determining whether to operate in regular DRX mode or modified DRX mode. Here, mode determination unit 230 may determine whether the number of consecutive paging occasions meets at least a threshold number (e.g., 2, 3, 4, etc.). In this implementation, when the threshold number of consecutive paging occasions is met, mode determination unit 230 may activate modified DRX mode unit 234 such that DRX module 216 operates using modified DRX. Otherwise, when this threshold is not met, mode determination unit 230 may activate regular DRX mode unit 232.

[0050] In another example implementations, the number of consecutive paging occasions may be but one of two or more conditions used in determining whether to operate in regular DRX mode or modified DRX mode by mode determination unit 230. Here, the channel quality may also need to meet a threshold level before mode determination unit 230 selects modified DRX mode. For example, if a signal -to-interference and noise ratio (SINR) is used as the channel quality indicator, user equipment 102 can typically decode the paging information correctly with one trial, if the SINR is larger than 10 dB. Thus, 10 dB can be set as a threshold to enable/disable the proposed algorithm. The threshold can be further optimized based on user equipment implementation. For example, measurement unit 244 may measure a channel quality based on one or more characteristics of the RF signal received from the RF chip 204. The channel quality measurements of the RF signal may include one or more of, e.g., a signal-to-noise ratio (SNR), a SINR, a received signal strength indicator (RSSI), a reference signal received quality (RSRQ), and/or a reference signal received power (RSRP). The channel quality measurements may be sent to mode determination unit 230 for comparison with the associated channel quality threshold(s), e.g., such as SNR or SINR threshold of 10 dB, RSRQ threshold of -5 dB, RSRP of -80 dBm, RSSI of - 90 dBm. Additionally and/or alternatively, the channel quality measurement may be sent to database unit 242. The channel quality measurement may be averaged with previous channel quality measurements associated with the base station and/or tracking area. The updated average channel quality measurement may be sent to mode determination unit 230, which may use this average in DRX mode selection.

[0051] In some implementations, the measure of channel quality may be the sole condition used by mode determination unit 230 in determining whether to operate in regular DRX mode or modified DRX mode. Here, when the channel quality measurement meets the channel quality threshold, mode determination unit 230 may active modified DRX mode unit 234. Otherwise, when the channel quality measurement fails to meet the channel quality threshold, mode determination unit 230 may active regular DRX mode unit 232.

[0052] The channel quality measurement may be sent to probability unit 246, which predicts the decoding probability P after m trials, e.g., P[l], P[2], P[3], ..., P[m] Selection unit 240 may then use these probabilities to determine the minimum number of paging occasions M out of Nnew or n (depending on the implementation) that can be monitored and still achieve the desired success rate R such that P[M]> R. For example, if M is equal to two and Nnew is equal to four, then monitoring unit 236 may monitor every other paging occasion. On the other hand, if M is equal to two and Nnew is equal to six, then monitoring unit 236 may monitor every third paging occasion.

[0053] Thus, using the techniques described above, a UE may be configured to operate in modified DRX mode to increase performance and reduce power consumption under a certain threshold, as compared to conventional UEs that are only configured to operate in regular DRX mode. This increase in performance and reduction in power consumption may be associated with the modified DRX cycle 306 (e.g., longer than 1.28s) that enables a UE to remain in sleep mode/low-power mode longer than a conventional DRX cycle 304 (e.g., 1.28s).

[0054] FIG. 4 illustrates a flowchart of an exemplary method 400 of DRX mode selection, according to embodiments of the disclosure. Exemplary method 400 may be performed by an apparatus for wireless communication, e.g., such as UE 102, apparatus 200, baseband chip 202, DRX module 216, RF chip 204, and/or node 500. Method 400 may include steps 402-414 as described below. It is to be appreciated that some of the steps may be optional, and some of the steps may be performed simultaneously, or in a different order than shown in FIG. 4A.

[0055] At 402, the apparatus may connect to the network. For example, referring to FIG.

1, UE 102 may connect to access node 104 (e.g., base station) to begin wireless communication. [0056] At 404, the apparatus may determine a paging transmission pattern used by the base station and/or base stations within the same tracking area. For example, referring to FIG. 2B, paging transmission pattern unit 238 may determine the paging transmission pattern used by the serving base station. As mentioned above, a paging transmission pattern may be defined as the number of consecutive paging occasions used by the serving base station and/or tracking area (e.g., group of cells) to transmit a repeating paging transmission. As also mentioned above, when the cell covers a large service area, the base station may use two or more consecutive paging occasions to repeat the transmission of the same paging occasion to increase the probability that the paging transmission is properly decoded. The paging transmission pattern may be determined in various ways, as described below. Each time the UE connects to a particular serving cell and/or tracking area, monitoring unit 236 may monitor paging occasions in regular DRX mode and send information associated with the number of consecutive paging occasions used for repeat transmissions to paging transmission pattern unit 238. From the information received from monitoring unit 236, paging transmission pattern unit 238 may determine the number of consecutive paging occasions used by the base station and/or tracking area, and hence, the paging transmission pattern. When it is unlikely that the number of consecutive paging occasions will change while the UE is connected to the network, paging transmission pattern unit 238 may send the number of instantaneous consecutive paging occasions (e.g., n) to mode determination unit. Otherwise, when there is a possibility that the number of consecutive paging occasions may change while the UE is connected to the network, paging transmission pattern unit 238 may access database unit 242 to obtain previous data associated with a previous average number of consecutive paging occasions (e.g., N_previous). Then, a new moving average (e.g., Nnew) of the number of consecutive paging occasions used by the base station and/or tracking for repeat paging transmissions may be computed as shown above in Equation (1).

[0057] At 406, the apparatus may determine channel conditions of communication with the base station. For example, referring to FIG. 2B, measurement unit 244 may measure a channel quality based on one or more characteristics of the RF signal received from the RF chip 204. The channel quality measurements of the RF signal may include one or more of, e.g., an SNR, an SINR, an RSSI, an RSRQ, and/or an RSRP. The channel quality measurements may be sent to mode determination unit 230 for comparison with the associated channel quality threshold(s).

[0058] At 408, the apparatus may update a database to include information associated with one or more of the paging transmission pattern and/or channel conditions. For example, referring to FIG. 2B, when there is a possibility that the number of consecutive paging occasions may change while the UE is connected to the network, paging transmission pattern unit 238 may access database unit 242 to obtain previous data associated with a previous average number of consecutive paging occasions (e.g., N_previous). Then, a new moving average (e.g., Nnew) of the number of consecutive paging occasions used by the base station and/or tracking for repeat paging transmissions may be computed as shown above in Equation (1). The value(s) of Nnew and n may be sent to update database unit 242 with the most recent paging transmission pattern information. Additionally and/or alternatively, the channel quality measurement obtained by measurement unit 244 may be sent to database unit 242. The channel quality measurement may be averaged with previous channel quality measurements associated with the base station and/or tracking area. The updated average channel quality measurement may be sent to mode determination unit 230, which may use this average in DRX mode selection.

[0059] At 410, the apparatus may determine whether the threshold condition(s) are met.

For example, referring to FIG. 2B, in one example implementation, the number of consecutive paging occasions (e.g., Nnew or n) may be the sole condition used in determining whether to operate in regular DRX mode or modified DRX mode. Here, mode determination unit 230 may determine whether the number of consecutive paging occasions meets at least a threshold number (e.g., 2, 3, 4, etc.). In this implementation, when the threshold number of consecutive paging occasions is met, mode determination unit 230 may activate modified DRX mode unit 234 such that DRX module 216 operates using modified DRX. Otherwise, when this threshold is not met, mode determination unit 230 may activate regular DRX mode unit 232. In another example implementations, the number of consecutive paging occasions may be but one of two or more conditions used in determining whether to operate in regular DRX mode or modified DRX mode by mode determination unit 230. Here, the channel quality may also need to meet a threshold level before mode determination unit 230 selects modified DRX mode. In still another example implementation, the measurement of channel quality may be the sole condition used by mode determination unit 230 in determining whether to operate in regular DRX mode or modified DRX mode. Here, when the channel quality measurement meets the channel quality threshold, mode determination unit 230 may active modified DRX mode unit 234. Otherwise, when the channel quality measurement fails to meet the channel quality threshold, mode determination unit 230 may active regular DRX mode unit 232.

[0060] At 412, the apparatus may operate in modified DRX mode. For example, referring to FIG. 2B, modified DRX mode unit 234 may be activated when mode determination unit 230 determines that the one or more threshold conditions relating to the paging transmission pattern and/or the channel quality measurement are met. A timing diagram 350 illustrating modified DRX mode is depicted in FIG. 3B.

[0061] At 414, the apparatus may operate in regular DRX mode. For example, referring to

FIG. 2B, regular DRX mode unit 232 may be activated when mode determination unit 230 determines that the one or more threshold conditions relating to the paging transmission pattern and/or the channel quality measurement are not met. A timing diagram 300 illustrating regular DRX mode is depicted in FIG. 3 A.

[0062] In various aspects of the present disclosure, the functions described herein may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or encoded as instructions or code on a non-transitory computer-readable medium. Computer-readable media includes computer storage media. Storage media may be any available media that can be accessed by a computing device, such as node 500 in FIG. 5. By way of example, and not limitation, such computer-readable media can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, HDD, such as magnetic disk storage or other magnetic storage devices, Flash drive, SSD, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a processing system, such as a mobile device or a computer. Disk and disc, as used herein, includes CD, laser disc, optical disc, digital video disc (DVD), and floppy disk where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media. [0063] According to one aspect of the present disclosure, a first apparatus for wireless communication of a UE is disclosed. The apparatus may include a DRX module. The DRX module may include a mode determination unit configured to determine whether to enter a modified DRX mode based on at least one threshold condition. The modified DRX mode may include monitoring a subset of paging occasions used by a serving base station. The DRX module may further include a modified DRX mode unit configured to operate using the modified DRX mode when the at least one threshold condition is met. The DRX module may include a monitoring unit configured to monitor the subset of paging occasions while in the modified DRX mode. [0064] In some embodiments, the DRX module may further include a paging transmission pattern unit configured to determine a paging transmission pattern used by the serving base station. The paging transmission pattern may include two or more consecutive paging occasions used to transmit a same paging indication by the serving base station. In some other embodiments, the DRX module may further include a selection unit configured to select the subset of paging occasions to monitor while in the modified DRX mode based at least in part on the paging transmission pattern.

[0065] In some embodiments, the at least one threshold condition may be met when the paging transmission pattern includes at least two consecutive paging occasions.

[0066] In some embodiments, the DRX module may further include a database unit configured to update paging transmission pattern information associated with the serving base station based on the paging transmission pattern.

[0067] In some embodiments, the DRX module may further include a measurement unit configured to measure a channel quality associated with the serving base station. In some other embodiments, the DRX module may further include a probability unit configured to determine a probability of correctly decoding a paging transmission using the subset of paging occasions. [0068] In some embodiments, the at least one threshold condition is met when the probability of correctly decoding the paging transmission using the subset of paging occasions meets a threshold probability.

[0069] In some embodiments, the channel quality may include one or more of an SNR, an

SINR, an RSSI, an RSRQ, or an RSRP.

[0070] According to another aspect of the present disclosure, a second apparatus for wireless communication of a UE is disclosed. The apparatus may include a memory and at least one processor coupled to the memory. The at least one processor may be configured to determine whether to enter a modified DRX mode based on at least one threshold condition. The modified DRX mode may include monitoring a subset of paging occasions used by a serving base station. The at least one processor may be further configured to enter the modified DRX mode when the at least one threshold condition is met. The at least one processor may be further configured to monitor the subset of paging occasions while in the modified DRX mode.

[0071] In some embodiments, the at least one processor may be further configured to determine a paging transmission pattern used by the serving base station. The paging transmission pattern may include two or more consecutive paging occasions used to transmit a same paging indication by the serving base station. In some other embodiments, the at least one processor may be further configured to select the subset of paging occasions to monitor while in the modified DRX mode based at least in part on the paging transmission pattern.

[0072] In some embodiments, the at least one threshold condition may be met when the paging transmission pattern includes at least two consecutive paging occasions.

[0073] In some embodiments, the at least one processor may be further configured to update paging transmission pattern information associated with the serving base station based on the paging transmission pattern.

[0074] In some embodiments, the at least one processor may be further configured to measure a channel quality associated with the serving base station. In some other embodiments, the at least one processor may be further configured to determine a probability of correctly decoding a paging transmission using the subset of paging occasions.

[0075] In some embodiments, the at least one threshold condition may be met when the probability of correctly decoding the paging transmission using the subset of paging occasions meets a threshold probability.

[0076] In some embodiments, the channel quality may include one or more of an SNR, an

SINR, an RSSI, an RSRQ, or an RSRP.

[0077] According to another aspect of the present disclosure, a method for wireless communication of a UE is disclosed. The method may include determining whether to enter a modified DRX mode based on at least one threshold condition. The modified DRX mode may include monitoring a subset of paging occasions used by a serving base station. The method may further include entering the modified DRX mode when the at least one threshold condition is met. The method may further include monitoring the subset of paging occasions while in the modified DRX mode.

[0078] In some embodiments, the method may further include determining a paging transmission pattern used by the serving base station, the paging transmission pattern including two or more consecutive paging occasions used to transmit a same paging indication by the serving base station. In some other embodiments, the method may further include selecting the subset of paging occasions to monitor while in the modified DRX mode based at least in part on the paging transmission pattern.

[0079] In some embodiments, the at least one threshold condition may be met when the paging transmission pattern includes at least two consecutive paging occasions.

[0080] In some embodiments, the method may further include updating paging transmission pattern information associated with the serving base station based on the paging transmission pattern.

[0081] In some embodiments, the method may further include measuring a channel quality associated with the serving base station. In some other embodiments, the method may further include determining a probability of correctly decoding a paging transmission using the subset of paging occasions.

[0082] In some embodiments, the at least one threshold condition may be met when the probability of correctly decoding the paging transmission using the subset of paging occasions meets a threshold probability. In some other embodiments, the channel quality may include one or more of an SNR, an SINR, an RSSI, an RSRQ, or an RSRP.

[0083] The foregoing description of the specific embodiments will so reveal the general nature of the present disclosure that others can, by applying knowledge within the skill of the art, readily modify and/or adapt for various applications such specific embodiments, without undue experimentation, without departing from the general concept of the present disclosure. Therefore, such adaptations and modifications are intended to be within the meaning and range of equivalents of the disclosed embodiments, based on the teaching and guidance presented herein. It is to be understood that the phraseology or terminology herein is for the purpose of description and not of limitation, such that the terminology or phraseology of the present specification is to be interpreted by the skilled artisan in light of the teachings and guidance.

[0084] Embodiments of the present disclosure have been described above with the aid of functional building blocks illustrating the implementation of specified functions and relationships thereof. The boundaries of these functional building blocks have been arbitrarily defined herein for the convenience of the description. Alternate boundaries can be defined so long as the specified functions and relationships thereof are appropriately performed.

[0085] The Summary and Abstract sections may set forth one or more but not all exemplary embodiments of the present disclosure as contemplated by the inventor(s), and thus, are not intended to limit the present disclosure and the appended claims in any way.

[0086] Various functional blocks, modules, and steps are disclosed above. The particular arrangements provided are illustrative and without limitation. Accordingly, the functional blocks, modules, and steps may be re-ordered or combined in different ways than in the examples provided above. Likewise, some embodiments include only a subset of the functional blocks, modules, and steps, and any such subset is permitted.

[0087] The breadth and scope of the present disclosure should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.

Claims

WHAT IS CLAIMED IS:

1. An apparatus for wireless communication of a user equipment (UE), comprising: a discontinuous reception (DRX) module comprising: a mode determination unit configured to determine whether to enter a modified DRX mode based on at least one threshold condition, the modified DRX mode including monitoring a subset of paging occasions used by a serving base station; a modified DRX mode unit configured to operate using the modified DRX mode when the at least one threshold condition is met; and a monitoring unit configured to monitor the subset of paging occasions while in the modified DRX mode.

2. The apparatus of claim 1, wherein the DRX unit further comprises: a paging transmission pattern unit configured to determine a paging transmission pattern used by the serving base station, the paging transmission pattern including two or more consecutive paging occasions used to transmit a same paging indication by the serving base station; and a selection unit configured to select the subset of paging occasions to monitor while in the modified DRX mode based at least in part on the paging transmission pattern.

3. The apparatus of claim 2, wherein the at least one threshold condition is met when the paging transmission pattern includes at least two consecutive paging occasions.

4. The apparatus of claim 2, wherein the DRX unit further comprises: a database unit configured to update paging transmission pattern information associated with the serving base station based on the paging transmission pattern.

5. The apparatus of claim 1, wherein the DRX unit further comprises: a measurement unit configured to measure a channel quality associated with the serving base station; and a probability unit configured to determine a probability of correctly decoding a paging transmission using the subset of paging occasions.

6 The apparatus of claim 5, wherein the at least one threshold condition is met when the probability of correctly decoding the paging transmission using the subset of paging occasions meets a threshold probability.

7. The apparatus of claim 6, wherein the channel quality includes one or more of a signal-to- noise ratio (SNR), a signal-to-interference and noise ratio (SINR), a received signal strength indicator (RSSI), a reference signal received quality (RSRQ), or a reference signal received power (RSRP).

8. An apparatus for wireless communication of a user equipment (UE), comprising: a memory; and at least one processor coupled to the memory and configured to: determine whether to enter a modified DRX mode based on at least one threshold condition, the modified DRX mode including monitoring a subset of paging occasions used by a serving base station; enter the modified DRX mode when the at least one threshold condition is met; and monitor the subset of paging occasions while in the modified DRX mode.

9. The apparatus of claim 8, wherein the at least one processor is further configured to: determine a paging transmission pattern used by the serving base station, the paging transmission pattern including two or more consecutive paging occasions used to transmit a same paging indication by the serving base station; and select the subset of paging occasions to monitor while in the modified DRX mode based at least in part on the paging transmission pattern.

10. The apparatus of claim 9, wherein the at least one threshold condition is met when the paging transmission pattern includes at least two consecutive paging occasions.

11. The apparatus of claim 9, wherein the at least one processor is further configured to: update paging transmission pattern information associated with the serving base station based on the paging transmission pattern.

12. The apparatus of claim 8, wherein the at least one processor is further configured to: measure a channel quality associated with the serving base station; and determine a probability of correctly decoding a paging transmission using the subset of paging occasions.

13. The apparatus of claim 12, wherein the at least one threshold condition is met when the probability of correctly decoding the paging transmission using the subset of paging occasions meets a threshold probability.

14. The apparatus of claim 13, wherein the channel quality includes one or more of a signal- to-noise ratio (SNR), a signal -to-interference and noise ratio (SINR), a received signal strength indicator (RSSI), a reference signal received quality (RSRQ), or a reference signal received power (RSRP).

15. A method for wireless communication of a user equipment (UE), comprising: determining whether to enter a modified DRX mode based on at least one threshold condition, the modified DRX mode including monitoring a subset of paging occasions used by a serving base station; entering the modified DRX mode when the at least one threshold condition is met; and monitoring the subset of paging occasions while in the modified DRX mode.

16. The method of claim 15, further comprising: determining a paging transmission pattern used by the serving base station, the paging transmission pattern including two or more consecutive paging occasions used to transmit a same paging indication by the serving base station; and selecting the subset of paging occasions to monitor while in the modified DRX mode based at least in part on the paging transmission pattern.

17. The method of claim 16, wherein the at least one threshold condition is met when the paging transmission pattern includes at least two consecutive paging occasions.

18. The method of claim 16, further comprising: updating paging transmission pattern information associated with the serving base station based on the paging transmission pattern.

19. The method of claim 15, further comprising: measuring a channel quality associated with the serving base station; and determining a probability of correctly decoding a paging transmission using the subset of paging occasions.

20. The method of claim 19, wherein: the at least one threshold condition is met when the probability of correctly decoding the paging transmission using the subset of paging occasions meets a threshold probability, and the channel quality includes one or more of a signal -to-noise ratio (SNR), a signal-to- interference and noise ratio (SINR), a received signal strength indicator (RSSI), a reference signal received quality (RSRQ), or a reference signal received power (RSRP).