WO2018039179A1

WO2018039179A1 - Enhanced key frame protection on cellular networks

Info

Publication number: WO2018039179A1
Application number: PCT/US2017/047927
Authority: WO
Inventors: Jerome Parron; Stefania Sesia; Debdeep CHATTERJEE; Marta MARTINEZ TARRADELL
Original assignee: Intel IP Corporation
Priority date: 2016-08-22
Filing date: 2017-08-22
Publication date: 2018-03-01

Abstract

Systems and methods of protecting key frames are generally described. A device detects the key frame based on packet inspection of a protocol header or payload field, a payload size, or a message transmitted between protocol layers. The modulation scheme, coding rate or number of maximum retransmissions is dependent on the frame type. The presence of the key frame may be indicated in a DCI that contains parameters that correspond to whether the key frame is to be encoded in a transparent or non-transparent manner, or which protection to use when the key frame is to be transmitted, or in a BSR, a data volume indication or a MAC Control Element. An uplink grant provides increased robustness for transmission of the key frame compared to robustness of an uplink grant for transmission of a normal frame.

Description

ENHANCED KEY FRAME PROTECTION ON CELLULAR

NETWORKS

PRIORITY CLAIM

[0001] This application claims the benefit of priority to U.S. Provisional

Patent Application Serial No. 62/378,121, filed August 22, 2016, entitled "Enhanced Key Frame Protection On Cellular Networks," which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

[0002] Embodiments pertain to radio access networks. Some embodiments relate to communication efficiency in networks including cellular and wireless local area network (WLAN) networks, including Third Generation Partnership Project Long Term Evolution (3 GPP LTE) networks and LTE advanced (LTE- A) networks as well as 4^th generation (4G) networks and 5^th generation (5G) networks.

BACKGROUND

[0003] The use of 3GPP LTE systems (including both LTE and LTE-A systems) has increased due to both an increase in the types of devices user equipment (UEs) using network resources as well as the amount of data and bandwidth being used by various applications, such as video streaming, operating on these UEs. Due to the increase in the types of UEs, as well as the amount and type of content communicated between the UEs and the evolved NodeB (eNB) or other UEs, network usage is continually increasing. The rapid increase in network use, along with the limited availability of bandwidth, may result in a constant drive towards efficient use of network resources.

BRIEF DESCRIPTION OF THE FIGURES

[0004] In the figures, which are not necessarily drawn to scale, like numerals may describe similar components in different views. Like numerals having different letter suffixes may represent different instances of similar components. The figures illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document.

[0005] FIG. 1 illustrates an architecture of a system of a network in accordance with some embodiments.

[0006] FIG. 2 illustrates example components of a device in accordance with some embodiments.

[0007] FIG. 3 illustrates example interfaces of baseband circuitry in accordance with some embodiments.

[0008] FIG. 4 is an illustration of a control plane protocol stack in accordance with some embodiments.

[0009] FIG. 5 is an illustration of a user plane protocol stack in accordance with some embodiments.

[0010] FIG. 6 is a block diagram illustrating components, according to some example embodiments, able to read instructions from a machine-readable or computer-readable medium (e.g., a non-transitory machine-readable storage medium) and perform any one or more of the methodologies discussed herein.

[0011] FIG. 7 illustrates communication flow in accordance with some embodiments.

[0012] FIG. 8 illustrates a flowchart of network communication in accordance with some embodiments.

DETAILED DESCRIPTION

[0013] The following description and the drawings sufficiently illustrate specific embodiments to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. Portions and features of some embodiments may be included in, or substituted for, those of other embodiments. Embodiments set forth in the claims encompass all available equivalents of those claims.

[0014] FIG. 1 illustrates an architecture of a system 100 of a network in accordance with some embodiments. The system 100 is shown to include a user equipment (UE) 101 and a UE 102. The UEs 101 and 102 are illustrated as smartphones (e.g., handheld touchscreen mobile computing devices connectable to one or more cellular networks), but may also comprise any mobile or non- mobile computing device, such as Personal Data Assistants (PDAs), pagers, laptop computers, desktop computers, wireless handsets, or any computing device including a wireless communications interface.

[0015] In some embodiments, any of the UEs 101 and 102 can comprise an Internet of Things (IoT) UE, which can comprise a network access layer designed for low-power IoT applications utilizing short-lived UE connections. An IoT UE can utilize technologies such as machine-to-machine (M2M) or machine-type communications (MTC) for exchanging data with an MTC server or device via a public land mobile network (PLMN), Proximity-Based Service (ProSe) or device-to-device (D2D) communication, sensor networks, or IoT networks. The M2M or MTC exchange of data may be a machine-initiated exchange of data. An IoT network describes interconnecting IoT UEs, which may include uniquely identifiable embedded computing devices (within the Internet infrastructure), with short-lived connections. The IoT UEs may execute background applications (e.g., keep-alive messages, status updates, etc.) to facilitate the connections of the IoT network.

[0016] The UEs 101 and 102 may be configured to connect, e.g., communicatively couple, with a radio access network (RAN) 110 - the RAN 110 may be, for example, an Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN), a NextGen RAN (NG RAN), or some other type of RAN. The UEs 101 and 102 utilize connections 103 and 104, respectively, each of which comprises a physical communications interface or layer (discussed in further detail below); in this example, the connections 103 and 104 are illustrated as an air interface to enable

communicative coupling, and can be consistent with cellular communications protocols, such as a Global System for Mobile Communications (GSM) protocol, a code-division multiple access (CDMA) network protocol, a Push-to- Talk (PTT) protocol, a PTT over Cellular (POC) protocol, a Universal Mobile Telecommunications System (UMTS) protocol, a 3GPP Long Term Evolution (LTE) protocol, a 5G protocol, a New Radio (NR) protocol, and the like.

[0017] In this embodiment, the UEs 101 and 102 may further directly exchange communication data via a ProSe interface 105. The ProSe interface 105 may alternatively be referred to as a sidelink interface comprising one or more logical channels, including but not limited to a Physical Sidelink Control Channel (PSCCH), a Physical Sidelink Shared Channel (PSSCH), a Physical Sidelink Discovery Channel (PSDCH), and a Physical Sidelink Broadcast Channel (PSBCH).

[0018] The UE 102 is shown to be configured to access an access point

(AP) 106 via connection 107. The connection 107 can comprise a local wireless connection, such as a connection consistent with any IEEE 802.11 protocol, wherein the AP 106 would comprise a wireless fidelity (WiFi®) router. In this example, the AP 106 is shown to be connected to the Internet without connecting to the core network of the wireless system (described in further detail below).

[0019] The RAN 110 can include one or more access nodes that enable the connections 103 and 104. These access nodes (ANs) can be referred to as base stations (BSs), NodeBs, evolved NodeBs (eNBs), next Generation NodeBs (gigabit NodeBs - gNBs), RAN nodes, and so forth, and can comprise ground stations (e.g., terrestrial access points) or satellite stations providing coverage within a geographic area (e.g., a cell). The RAN 110 may include one or more RAN nodes for providing macrocells, e.g., macro RAN node 111, and one or more RAN nodes for providing femtocells or picocells (e.g., cells having smaller coverage areas, smaller user capacity, or higher bandwidth compared to macrocells), e.g., low power (LP) RAN node 112.

[0020] Any of the RAN nodes 111 and 112 can terminate the air interface protocol and can be the first point of contact for the UEs 101 and 102. In some embodiments, any of the RAN nodes 111 and 112 can fulfill various logical functions for the RAN 110 including, but not limited to, radio network controller (RNC) functions such as radio bearer management, uplink and downlink dynamic radio resource management and data packet scheduling, and mobility management.

[0021] In accordance with some embodiments, the UEs 101 and 102 can be configured to communicate using Orthogonal Frequency-Division

Multiplexing (OFDM) communication signals with each other or with any of the RAN nodes 111 and 112 over a multicarrier communication channel in accordance various communication techniques, such as, but not limited to, an Orthogonal Frequency -Division Multiple Access (OFDMA) communication technique (e.g., for downlink communications) or a Single Carrier Frequency Division Multiple Access (SC-FDMA) communication technique (e.g., for uplink and ProSe or sidelink communications), although the scope of the embodiments is not limited in this respect. The OFDM signals can comprise a plurality of orthogonal subcarriers.

[0022] In some embodiments, a downlink resource grid can be used for downlink transmissions from any of the RAN nodes 111 and 112 to the UEs 101 and 102, while uplink transmissions can utilize similar techniques. The grid can be a time-frequency grid, called a resource grid or time-frequency resource grid, which is the physical resource in the downlink in each slot. Such a time- frequency plane representation is a common practice for OFDM systems, which makes it intuitive for radio resource allocation. Each column and each row of the resource grid corresponds to one OFDM symbol and one OFDM subcarrier, respectively. The duration of the resource grid in the time domain corresponds to one slot in a radio frame. The smallest time-frequency unit in a resource grid is denoted as a resource element. Each resource grid comprises a number of resource blocks, which describe the mapping of certain physical channels to resource elements. Each resource block comprises a collection of resource elements; in the frequency domain, this may represent the smallest quantity of resources that currently can be allocated. There are several different physical downlink channels that are conveyed using such resource blocks.

[0023] The physical downlink shared channel (PDSCH) may carry user data and higher-layer signaling to the UEs 101 and 102. The physical downlink control channel (PDCCH) may carry information about the transport format and resource allocations related to the PDSCH channel, among other things. It may also inform the UEs 101 and 102 about the transport format, resource allocation, and H-ARQ (Hybrid Automatic Repeat Request) information related to the uplink shared channel. Typically, downlink scheduling (assigning control and shared channel resource blocks to the UE 102 within a cell) may be performed at any of the RAN nodes 111 and 112 based on channel quality information fed back from any of the UEs 101 and 102. The downlink resource assignment information may be sent on the PDCCH used for (e.g., assigned to) each of the UEs 101 and 102.

[0024] The PDCCH may use control channel elements (CCEs) to convey the control information. Before being mapped to resource elements, the PDCCH complex- valued symbols may first be organized into quadruplets, which may then be permuted using a sub-block interleaver for rate matching. Each PDCCH may be transmitted using one or more of these CCEs, where each CCE may correspond to nine sets of four physical resource elements known as resource element groups (REGs). Four Quadrature Phase Shift Keying (QPSK) symbols may be mapped to each REG. The PDCCH can be transmitted using one or more CCEs, depending on the size of the downlink control information (DCI) and the channel condition. There can be four or more different PDCCH formats defined in LTE with different numbers of CCEs (e.g., aggregation level, L=l, 2, 4, or 8).

[0025] Some embodiments may use concepts for resource allocation for control channel information that are an extension of the above-described concepts. For example, some embodiments may utilize an enhanced physical downlink control channel (EPDCCH) that uses PDSCH resources for control information transmission. The EPDCCH may be transmitted using one or more enhanced the control channel elements (ECCEs). Similar to above, each ECCE may correspond to nine sets of four physical resource elements known as an enhanced resource element groups (EREGs). An ECCE may have other numbers of EREGs in some situations. [0026] The RAN 110 is shown to be communicatively coupled to a core network (CN) 120— via an SI interface 113. In embodiments, the CN 120 may be an evolved packet core (EPC) network, a NextGen Packet Core (NPC) network, or some other type of CN. In this embodiment, the SI interface 113 is split into two parts: the Sl-U interface 114, which carries traffic data between the RAN nodes 111 and 112 and the serving gateway (S-GW) 122, and the Sl- mobility management entity (MME) interface 115, which is a signaling interface between the RAN nodes 111 and 112 and MMEs 121.

[0027] In this embodiment, the CN 120 comprises the MMEs 121, the S- GW 122, the Packet Data Network (PDN) Gateway (P-GW) 123, and a home subscriber server (HSS) 124. The MMEs 121 may be similar in function to the control plane of legacy Serving General Packet Radio Service (GPRS) Support Nodes (SGSN). The MMEs 121 may manage mobility aspects in access such as gateway selection and tracking area list management. The HSS 124 may comprise a database for network users, including subscription-related information to support the network entities' handling of communication sessions. The CN 120 may comprise one or several HSSs 124, depending on the number of mobile subscribers, on the capacity of the equipment, on the organization of the network, etc. For example, the HSS 124 can provide support for routing/roaming, authentication, authorization, naming/addressing resolution, location dependencies, etc.

[0028] The S-GW 122 may terminate the SI interface 113 towards the

RAN 110, and routes data packets between the RAN 110 and the CN 120. In addition, the S-GW 122 may be a local mobility anchor point for inter-RAN node handovers and also may provide an anchor for inter-3GPP mobility. Other responsibilities may include lawful intercept, charging, and some policy enforcement.

[0029] The P-GW 123 may terminate an SGi interface toward a PDN.

The P-GW 123 may route data packets between the EPC network 123 and external networks such as a network including the application server 130

(alternatively referred to as application function (AF)) via an Internet Protocol (IP) interface 125. Generally, the application server 130 may be an element offering applications that use IP bearer resources with the core network (e.g., UMTS Packet Services (PS) domain, LTE PS data services, etc.). In this embodiment, the P-GW 123 is shown to be communicatively coupled to an application server 130 via an IP communications interface 125. The application server 130 can also be configured to support one or more communication services (e.g., Voice-over-Internet Protocol (VoIP) sessions, PTT sessions, group communication sessions, social networking services, etc.) for the UEs 101 and 102 via the CN 120.

[0030] The P-GW 123 may further be a node for policy enforcement and charging data collection. Policy and Charging Enforcement Function (PCRF) 126 is the policy and charging control element of the CN 120. In a non-roaming scenario, there may be a single PCRF in the Home Public Land Mobile Network (HPLMN) associated with a UE's Internet Protocol Connectivity Access Network (IP-CAN) session. In a roaming scenario with local breakout of traffic, there may be two PCRFs associated with a UE's IP-CAN session: a Home PCRF (H-PCRF) within a HPLMN and a Visited PCRF (V-PCRF) within a Visited Public Land Mobile Network (VPLMN). The PCRF 126 may be

communicatively coupled to the application server 130 via the P-GW 123. The application server 130 may signal the PCRF 126 to indicate a new service flow and select the appropriate Quality of Service (QoS) and charging parameters. The PCRF 126 may provision this rule into a Policy and Charging Enforcement Function (PCEF) (not shown) with the appropriate traffic flow template (TFT) and QoS class of identifier (QCI), which commences the QoS and charging as specified by the application server 130.

[0031] FIG. 2 illustrates example components of a device 200 in accordance with some embodiments. In some embodiments, the device 200 may include application circuitry 202, baseband circuitry 204, Radio Frequency (RF) circuitry 206, front-end module (FEM) circuitry 208, one or more antennas 210, and power management circuitry (PMC) 212 coupled together at least as shown. The components of the illustrated device 200 may be included in a UE or a RAN node. In some embodiments, the device 200 may include less elements (e.g., a RAN node may not utilize application circuitry 202, and instead include a processor/controller to process IP data received from an EPC). In some embodiments, the device 200 may include additional elements such as, for example, memory /storage, display, camera, sensor, or input/output (I/O) interface. In other embodiments, the components described below may be included in more than one device (e.g., said circuitries may be separately included in more than one device for Cloud-RAN (C-RAN) implementations).

[0032] The application circuitry 202 may include one or more application processors. For example, the application circuitry 202 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processor(s) may include any combination of general-purpose processors and dedicated processors (e.g., graphics processors,

application processors, etc.). The processors may be coupled with or may include memory /storage and may be configured to execute instructions stored in the memory /storage to enable various applications or operating systems to run on the device 200. In some embodiments, processors of application circuitry 202 may process IP data packets received from an EPC.

[0033] The baseband circuitry 204 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The baseband circuitry 204 may include one or more baseband processors or control logic to process baseband signals received from a receive signal path of the RF circuitry 206 and to generate baseband signals for a transmit signal path of the RF circuitry 206. Baseband processing circuity 204 may interface with the application circuitry 202 for generation and processing of the baseband signals and for controlling operations of the RF circuitry 206. For example, in some embodiments, the baseband circuitry 204 may include a third generation (3G) baseband processor 204A, a fourth generation (4G) baseband processor 204B, a 5G baseband processor 204C, or other baseband processor(s) 204D for other existing generations, generations in development or to be developed in the future (e.g., second generation (2G), sixth generation (6G), etc.). The baseband circuitry 204 (e.g., one or more of baseband processors 204A-D) may handle various radio control functions that enable communication with one or more radio networks via the RF circuitry 206. In other embodiments, some or all of the functionality of baseband processors 204 A-D may be included in modules stored in the memory 204G and executed via a Central Processing Unit (CPU) 204E. The radio control functions may include, but are not limited to, signal modulation/demodulation, encoding/decoding, radio frequency shifting, etc. In some embodiments, modulation/demodulation circuitry of the baseband circuitry 204 may include Fast-Fourier Transform (FFT), precoding, or constellation mapping/demapping functionality. In some embodiments, encoding/decoding circuitry of the baseband circuitry 204 may include convolution, tail-biting convolution, turbo, Viterbi, or Low Density Parity Check (LDPC)

encoder/decoder functionality. Embodiments of modulation/demodulation and encoder/decoder functionality are not limited to these examples and may include other suitable functionality in other embodiments.

[0034] In some embodiments, the baseband circuitry 204 may include one or more audio digital signal processor(s) (DSP) 204F. The audio DSP(s) 204F may be include elements for compression/decompression and echo cancellation and may include other suitable processing elements in other embodiments. Components of the baseband circuitry may be suitably combined in a single chip, a single chipset, or disposed on a same circuit board in some embodiments. In some embodiments, some or all of the constituent components of the baseband circuitry 204 and the application circuitry 202 may be implemented together such as, for example, on a system on a chip (SOC).

[0035] In some embodiments, the baseband circuitry 204 may provide for communication compatible with one or more radio technologies. For example, in some embodiments, the baseband circuitry 204 may support communication with an evolved universal terrestrial radio access network (EUTRAN) or other wireless metropolitan area networks (WMAN), a wireless local area network (WLAN), a wireless personal area network (WP AN).

Embodiments in which the baseband circuitry 204 is configured to support radio communications of more than one wireless protocol may be referred to as multi- mode baseband circuitry.

[0036] RF circuitry 206 may enable communication with wireless networks using modulated electromagnetic radiation through a non-solid medium. In various embodiments, the RF circuitry 206 may include switches, filters, amplifiers, etc. to facilitate the communication with the wireless network. RF circuitry 206 may include a receive signal path which may include circuitry to down-convert RF signals received from the FEM circuitry 208 and provide baseband signals to the baseband circuitry 204. RF circuitry 206 may also include a transmit signal path which may include circuitry to up-convert baseband signals provided by the baseband circuitry 204 and provide RF output signals to the FEM circuitry 208 for transmission.

[0037] In some embodiments, the receive signal path of the RF circuitry

206 may include mixer circuitry 206A, amplifier circuitry 206B and filter circuitry 206C. In some embodiments, the transmit signal path of the RF circuitry 206 may include filter circuitry 206C and mixer circuitry 206A. RF circuitry 206 may also include synthesizer circuitry 206D for synthesizing a frequency for use by the mixer circuitry 206A of the receive signal path and the transmit signal path. In some embodiments, the mixer circuitry 206A of the receive signal path may be configured to down-convert RF signals received from the FEM circuitry 208 based on the synthesized frequency provided by synthesizer circuitry 206D. The amplifier circuitry 206B may be configured to amplify the down-converted signals and the filter circuitry 206C may be a low- pass filter (LPF) or band-pass filter (BPF) configured to remove unwanted signals from the down-converted signals to generate output baseband signals. Output baseband signals may be provided to the baseband circuitry 204 for further processing. In some embodiments, the output baseband signals may be zero-frequency baseband signals, although this is not a requirement. In some embodiments, mixer circuitry 206A of the receive signal path may comprise passive mixers, although the scope of the embodiments is not limited in this respect. [0038] In some embodiments, the mixer circuitry 206A of the transmit signal path may be configured to up-convert input baseband signals based on the synthesized frequency provided by the synthesizer circuitry 206D to generate RF output signals for the FEM circuitry 208. The baseband signals may be provided by the baseband circuitry 204 and may be filtered by filter circuitry 206C.

[0039] In some embodiments, the mixer circuitry 206A of the receive signal path and the mixer circuitry 206A of the transmit signal path may include two or more mixers and may be arranged for quadrature downconversion and upconversion, respectively. In some embodiments, the mixer circuitry 206A of the receive signal path and the mixer circuitry 206A of the transmit signal path may include two or more mixers and may be arranged for image rej ection (e.g., Hartley image rejection). In some embodiments, the mixer circuitry 206A of the receive signal path and the mixer circuitry 206A may be arranged for direct downconversion and direct upconversion, respectively. In some embodiments, the mixer circuitry 206A of the receive signal path and the mixer circuitry 206A of the transmit signal path may be configured for super-heterodyne operation.

[0040] In some embodiments, the output baseband signals and the input baseband signals may be analog baseband signals, although the scope of the embodiments is not limited in this respect. In some alternate embodiments, the output baseband signals and the input baseband signals may be digital baseband signals. In these alternate embodiments, the RF circuitry 206 may include analog-to-digital converter (ADC) and digital-to-analog converter (DAC) circuitry and the baseband circuitry 204 may include a digital baseband interface to communicate with the RF circuitry 206.

[0041] In some dual-mode embodiments, a separate radio IC circuitry may be provided for processing signals for each spectrum, although the scope of the embodiments is not limited in this respect.

[0042] In some embodiments, the synthesizer circuitry 206D may be a fractional -N synthesizer or a fractional N/N+1 synthesizer, although the scope of the embodiments is not limited in this respect as other types of frequency synthesizers may be suitable. For example, synthesizer circuitry 206D may be a delta-sigma synthesizer, a frequency multiplier, or a synthesizer comprising a phase-locked loop with a frequency divider.

[0043] The synthesizer circuitry 206D may be configured to synthesize an output frequency for use by the mixer circuitry 206A of the RF circuitry 206 based on a frequency input and a divider control input. In some embodiments, the synthesizer circuitry 206D may be a fractional N/N+l synthesizer.

[0044] In some embodiments, frequency input may be provided by a voltage controlled oscillator (VCO), although that is not a requirement. Divider control input may be provided by either the baseband circuitry 204 or the applications processor 202 depending on the desired output frequency. In some embodiments, a divider control input (e.g., N) may be determined from a lookup table based on a channel indicated by the applications processor 202.

[0045] Synthesizer circuitry 206D of the RF circuitry 206 may include a divider, a delay -locked loop (DLL), a multiplexer and a phase accumulator. In some embodiments, the divider may be a dual modulus divider (DMD) and the phase accumulator may be a digital phase accumulator (DP A). In some embodiments, the DMD may be configured to divide the input signal by either N or N+1 (e.g., based on a carry out) to provide a fractional division ratio. In some example embodiments, the DLL may include a set of cascaded, tunable, delay elements, a phase detector, a charge pump and a D-type flip-flop. In these embodiments, the delay elements may be configured to break a VCO period up into Nd equal packets of phase, where Nd is the number of delay elements in the delay line. In this way, the DLL provides negative feedback to help ensure that the total delay through the delay line is one VCO cycle.

[0046] In some embodiments, synthesizer circuitry 206D may be configured to generate a carrier frequency as the output frequency, while in other embodiments, the output frequency may be a multiple of the carrier frequency (e.g., twice the carrier frequency, four times the carrier frequency) and used in conjunction with quadrature generator and divider circuitry to generate multiple signals at the carrier frequency with multiple different phases with respect to each other. In some embodiments, the output frequency may be a LO frequency (fLO). In some embodiments, the RF circuitry 206 may include an IQ/polar converter.

[0047] FEM circuitry 208 may include a receive signal path which may include circuitry configured to operate on RF signals received from one or more antennas 210, amplify the received signals and provide the amplified versions of the received signals to the RF circuitry 206 for further processing. FEM circuitry 208 may also include a transmit signal path which may include circuitry configured to amplify signals for transmission provided by the RF circuitry 206 for transmission by one or more of the one or more antennas 210. In various embodiments, the amplification through the transmit or receive signal paths may be done solely in the RF circuitry 206, solely in the FEM 208, or in both the RF circuitry 206 and the FEM 208.

[0048] In some embodiments, the FEM circuitry 208 may include a

TX/RX switch to switch between transmit mode and receive mode operation. The FEM circuitry may include a receive signal path and a transmit signal path. The receive signal path of the FEM circuitry may include an LNA to amplify received RF signals and provide the amplified received RF signals as an output (e.g., to the RF circuitry 206). The transmit signal path of the FEM circuitry 208 may include a power amplifier (PA) to amplify input RF signals (e.g., provided by RF circuitry 206), and one or more filters to generate RF signals for subsequent transmission (e.g., by one or more of the one or more antennas 210).

[0049] In some embodiments, the PMC 212 may manage power provided to the baseband circuitry 204. In particular, the PMC 212 may control power-source selection, voltage scaling, battery charging, or DC-to-DC conversion. The PMC 212 may often be included when the device 200 is capable of being powered by a battery, for example, when the device is included in a UE. The PMC 212 may increase the power conversion efficiency while providing desirable implementation size and heat dissipation characteristics.

[0050] While FIG. 2 shows the PMC 212 coupled only with the baseband circuitry 204. However, in other embodiments, the PMC 2 12 may be additionally or alternatively coupled with, and perform similar power management operations for, other components such as, but not limited to, application circuitry 202, RF circuitry 206, or FEM 208.

[0051] In some embodiments, the PMC 212 may control, or otherwise be part of, various power saving mechanisms of the device 200. For example, if the device 200 is in an RRC_Connected state, where it is still connected to the RAN node as it expects to receive traffic shortly, then it may enter a state known as Discontinuous Reception Mode (DRX) after a period of inactivity. During this state, the device 200 may power down for brief intervals of time and thus save power.

[0052] If there is no data traffic activity for an extended period of time, then the device 200 may transition to an RRC Idle state. In the RRC Idle state, the device 200 may disconnect from the network and avoid performing operations such as channel quality feedback, handover, etc. The device 200 may enter a very low power state and perform paging in which the device 200 may periodically wake up to listen to the network and then power down again. To receive data, the device 200 may transition back to the RRC_Connected state.

[0053] An additional power saving mode may allow a device to be unavailable to the network for periods longer than a paging interval (ranging from seconds to a few hours). During this time, the device is totally unreachable to the network and may power down completely. Any data sent during this time incurs a large delay and it is assumed the delay is acceptable.

[0054] Processors of the application circuitry 202 and processors of the baseband circuitry 204 may be used to execute elements of one or more instances of a protocol stack. For example, processors of the baseband circuitry 204, alone or in combination, may be used execute Layer 3, Layer 2, or Layer 1 functionality, while processors of the application circuitry 204 may utilize data (e.g., packet data) received from these layers and further execute Layer 4 functionality (e.g., transmission communication protocol (TCP) and user datagram protocol (UDP) layers). As referred to herein, Layer 3 may comprise a radio resource control (RRC) layer, described in further detail below. As referred to herein, Layer 2 may comprise a medium access control (MAC) layer, a radio link control (RLC) layer, and a packet data convergence protocol (PDCP) layer, described in further detail below. As referred to herein, Layer 1 may comprise a physical (PHY) layer of a UE/RAN node, described in further detail below.

[0055] FIG. 3 illustrates example interfaces of baseband circuitry in accordance with some embodiments. As discussed above, the baseband circuitry 204 of FIG. 2 may comprise processors 204A-XT04E and a memory 204G utilized by said processors. Each of the processors 204A-XT04E may include a memory interface, 304A-XU04E, respectively, to send/receive data to/from the memory 204G.

[0056] The baseband circuitry 204 may further include one or more interfaces to communicatively couple to other circuitries/devices, such as a memory interface 312 (e.g., an interface to send/receive data to/from memory external to the baseband circuitry 204), an application circuitry interface 314 (e.g., an interface to send/receive data to/from the application circuitry 202 of FIG. 2), an RF circuitry interface 316 (e.g., an interface to send/receive data to/from RF circuitry 206 of FIG. 2), a wireless hardware connectivity interface 318 (e.g., an interface to send/receive data to/from Near Field Communication (NFC) components, Bluetooth® components (e.g., Bluetooth® Low Energy), Wi-Fi® components, and other communication components), and a power management interface 320 (e.g., an interface to send/receive power or control signals to/from the PMC 212).

[0057] FIG. 4 is an illustration of a control plane protocol stack in accordance with some embodiments. In this embodiment, a control plane 400 is shown as a communications protocol stack between the UE 101 (or alternatively, the UE 102), the RAN node 1 11 (or alternatively, the RAN node 112), and the MME 121.

[0058] The PHY layer 401 may transmit or receive information used by the MAC layer 402 over one or more air interfaces. The PHY layer 401 may further perform link adaptation or adaptive modulation and coding (AMC), power control, cell search (e.g., for initial synchronization and handover purposes), and other measurements used by higher layers, such as the RRC layer 405. The PHY layer 401 may still further perform error detection on the transport channels, forward error correction (FEC) coding/decoding of the transport channels, modulation/demodulation of physical channels, interleaving, rate matching, mapping onto physical channels, and Multiple Input Multiple Output (MIMO) antenna processing.

[0059] The MAC layer 402 may perform mapping between logical channels and transport channels, multiplexing of MAC service data units (SDUs) from one or more logical channels onto transport blocks (TB) to be delivered to PHY via transport channels, de-multiplexing MAC SDUs to one or more logical channels from transport blocks (TB) delivered from the PHY via transport channels, multiplexing MAC SDUs onto TBs, scheduling information reporting, error correction through hybrid automatic repeat request (HARQ), and logical channel prioritization.

[0060] The RLC layer 403 may operate in a plurality of modes of operation, including: Transparent Mode (TM), Unacknowledged Mode (UM), and Acknowledged Mode (AM). The RLC layer 403 may execute transfer of upper layer protocol data units (PDUs), error correction through automatic repeat request (ARQ) for AM data transfers, and concatenation, segmentation and reassembly of RLC SDUs for UM and AM data transfers. The RLC layer 403 may also execute re-segmentation of RLC data PDUs for AM data transfers, reorder RLC data PDUs for UM and AM data transfers, detect duplicate data for UM and AM data transfers, discard RLC SDUs for UM and AM data transfers, detect protocol errors for AM data transfers, and perform RLC re-establishment.

[0061] The PDCP layer 404 may execute header compression and decompression of IP data, maintain PDCP Sequence Numbers (SNs), perform in-sequence delivery of upper layer PDUs at re-establishment of lower layers, eliminate duplicates of lower layer SDUs at re-establishment of lower layers for radio bearers mapped on RLC AM, cipher and decipher control plane data, perform integrity protection and integrity verification of control plane data, control timer-based discard of data, and perform security operations (e.g., ciphering, deciphering, integrity protection, integrity verification, etc.).

[0062] The main services and functions of the RRC layer 405 may include broadcast of system information (e.g., included in Master Information Blocks (MIBs) or System Information Blocks (SIBs) related to the non-access stratum (NAS)), broadcast of system information related to the access stratum (AS), paging, establishment, maintenance and release of an RRC connection between the UE and E-UTRAN (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), establishment, configuration, maintenance and release of point to point Radio Bearers, security functions including key management, inter radio access technology (RAT) mobility, and measurement configuration for UE

measurement reporting. Said MIBs and SIBs may comprise one or more information elements (IEs), which may each comprise individual data fields or data structures.

[0063] The UE 101 and the RAN node 111 may utilize a Uu interface

(e.g., an LTE-Uu interface) to exchange control plane data via a protocol stack comprising the PHY layer 401, the MAC layer 402, the RLC layer 403, the PDCP layer 404, and the RRC layer 405.

[0064] The non-access stratum (NAS) protocols 406 form the highest stratum of the control plane between the UE 101 and the MME 121. The NAS protocols 406 support the mobility of the UE 101 and the session management procedures to establish and maintain IP connectivity between the UE 101 and the P-GW 123.

[0065] The S 1 Application Protocol (S 1 -AP) layer 415 may support the functions of the SI interface and comprise Elementary Procedures (EPs). An EP is a unit of interaction between the RAN node 111 and the CN 120. The Sl-AP layer services may comprise two groups: UE-associated services and non UE- associated services. These services perform functions including, but not limited to: E-UTRAN Radio Access Bearer (E-RAB) management, UE capability indication, mobility, NAS signaling transport, RAN Information Management (RIM), and configuration transfer.

[0066] The Stream Control Transmission Protocol (SCTP) layer

(alternatively referred to as the SCTP/IP layer) 414 may ensure reliable delivery of signaling messages between the RAN node 111 and the MME 121 based, in part, on the IP protocol, supported by the IP layer 413. The L2 layer 412 and the LI layer 411 may refer to communication links (e.g., wired or wireless) used by the RAN node and the MME to exchange information.

[0067] The RAN node 111 and the MME 121 may utilize an SI -MME interface to exchange control plane data via a protocol stack comprising the LI layer 411, the L2 layer 412, the IP layer 413, the SCTP layer 414, and the Sl-AP layer 415.

[0068] FIG. 5 is an illustration of a user plane protocol stack in accordance with some embodiments. In this embodiment, a user plane 500 is shown as a communications protocol stack between the UE 101 (or alternatively, the UE 102), the RAN node 111 (or alternatively, the RAN node 112), the S-GW 122, and the P-GW 123. The user plane 500 may utilize at least some of the same protocol layers as the control plane 400. For example, the UE 101 and the RAN node 111 may utilize a Uu interface (e.g., an LTE-Uu interface) to exchange user plane data via a protocol stack comprising the PHY layer 401, the MAC layer 402, the RLC layer 403, the PDCP layer 404.

[0069] The General Packet Radio Service (GPRS) Tunneling Protocol for the user plane (GTP-U) layer 504 may be used for carrying user data within the GPRS core network and between the radio access network and the core network. The user data transported can be packets in any of IPv4, IPv6, or PPP formats, for example. The UDP and IP security (UDP/IP) layer 503 may provide checksums for data integrity, port numbers for addressing different functions at the source and destination, and encryption and authentication on the selected data flows. The RAN node 111 and the S-GW 122 may utilize an Sl-U interface to exchange user plane data via a protocol stack comprising the LI layer 411, the L2 layer 412, the UDP/IP layer 503, and the GTP-U layer 504. The S-GW 122 and the P-GW 123 may utilize an S5/S8a interface to exchange user plane data via a protocol stack comprising the LI layer 411, the L2 layer 412, the UDP/IP layer 503, and the GTP-U layer 504. As discussed above with respect to FIG. 4, NAS protocols support the mobility of the UE 101 and the session management procedures to establish and maintain IP connectivity between the UE 101 and the P-GW 123.

[0070] FIG. 6 is a block diagram illustrating components, according to some example embodiments, able to read instructions from a machine-readable or computer-readable medium (e.g., a non-transitory machine-readable storage medium) and perform any one or more of the methodologies discussed herein. Specifically, FIG. 6 shows a diagrammatic representation of hardware resources 600 including one or more processors (or processor cores) 610, one or more memory /storage devices 620, and one or more communication resources 630, each of which may be communicatively coupled via a bus 640. For

embodiments where node virtualization (e.g., NFV) is utilized, a hypervisor 602 may be executed to provide an execution environment for one or more network slices/sub-slices to utilize the hardware resources 600

[0071] The processors 610 (e.g., a central processing unit (CPU), a reduced instruction set computing (RISC) processor, a complex instruction set computing (CISC) processor, a graphics processing unit (GPU), a digital signal processor (DSP) such as a baseband processor, an application specific integrated circuit (ASIC), a radio-frequency integrated circuit (RFIC), another processor, or any suitable combination thereof) may include, for example, a processor 612 and a processor 614.

[0072] The memory /storage devices 620 may include main memory, disk storage, or any suitable combination thereof. The memory /storage devices 620 may include, but are not limited to any type of volatile or non-volatile memory such as dynamic random access memory (DRAM), static random-access memory (SRAM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), Flash memory, solid-state storage, etc. [0073] The communication resources 630 may include interconnection or network interface components or other suitable devices to communicate with one or more peripheral devices 604 or one or more databases 606 via a network 608. For example, the communication resources 630 may include wired communication components (e.g., for coupling via a Universal Serial Bus (USB)), cellular communication components, NFC components, Bluetooth® components (e.g., Bluetooth® Low Energy), Wi-Fi® components, and other communication components.

[0074] Instructions 650 may comprise software, a program, an application, an applet, an app, or other executable code for causing at least any of the processors 610 to perform any one or more of the methodologies discussed herein. The instructions 650 may reside, completely or partially, within at least one of the processors 610 (e.g., within the processor's cache memory), the memory /storage devices 620, or any suitable combination thereof. In some embodiments, the instructions 650 may reside on a tangible, nonvolatile communication device readable medium, which may include a single medium or multiple media. Furthermore, any portion of the instructions 650 may be transferred to the hardware resources 600 from any combination of the peripheral devices 604 or the databases 606. Accordingly, the memory of processors 610, the memory /storage devices 620, the peripheral devices 604, and the databases 606 are examples of computer-readable and machine-readable media.

[0075] As described above, network efficiency is increasingly of interest due to the number of UEs using network resources or that are soon to use network resources. FIG. 7 illustrates communication flow in accordance with some embodiments. The communication flow in the system 700 may originate from a first UE (UE1 702a). UE1 702a may be connected with the RAN via eNBl 704a such that packets from UE1 702a to UE2 702b may be provided to the eNBl 704a be relayed through the network 706 to eNB2 704b and then to UE2 702b. The various devices shown in FIG. 7 may have some or all of the circuitry shown in FIGS. 2-6. The connections between the UEs and the eNBs may be direct (e.g., using 3GPP protocols) and/or indirect (e.g., through access points using, for example, WiFi; or via D2D or V2X communications).

[0076] Although all communication between the UE 702 and eNB 704, may pass through the same radio bearers, not all of the frames or packets may be of the same importance to network communications. The frames may be of different types: a "key frame" or a "normal" frame. In some embodiments, communications present in the network may use multiple protocols, some of which may use a key frame whose information is used to properly handle the rest of the flow. A key frame may, for example, provide control signaling or critical data used to establish or negotiate a radio bearer or a communication link. A key frame may thus be a reference frame that contains information without which subsequent other frames cannot be decoded. An example of a key frame is the uncompressed header when Robust Header Compression (RoHC) is used for speech transmission (compression algorithm for header compression) or an uncompressed image for video transmissions (or media data compression in a typical audio or video codec). Consequently, a normal frame may be a frame that contains information that is based on the key frame.

[0077] The key frame may be a control plane frame (control key frame) used for control signaling or user plane frame (user key frame) that may contain user data. When the key frame is a user plane frame, the user data in the key frame may, in some embodiments, be compressed or, in other embodiments, uncompressed. Examples of a control key frame may include SIP signaling to establish a VoIP call or TCP signaling to establish a TCP connection. If a control key frame is lost, may lead to delay or failure of session establishment. Examples of a user key frame may include a video frame or PDCP packet with RoHC header in which the user key frame contains information used to decompress one or more subsequent frames. Examples of a normal frame may be the compressed header when RoHC is used for speech transmission or, for video, the frames that contain only the difference with respect to the

uncompressed image. Compressed frames may thus contain normal data that, if the corresponding critical frame is lost, may be unable to be decompressed. Key frames may be somewhat rare compared with normal frames, and may be provided once every 10-100 frames, for example. Although key packets may be used in the network, for convenience, the term key frame will only be used herein.

[0078] Normally, a certain amount of robustness may exist in a network and thereby provide a good experience for users interacting with the UE. Thus, for example, packets that are lost or encounter severe interference may be repeated by the transmitting device (UE or eNB) while later packets that are received with sufficient quality may be stored for correct assembly (timing) within the receiving device. In some cases, normal frames may be discarded if, even after repeated attempts, the data quality of a packet at the receiving device remains below a predetermined threshold.

[0079] In some cases, such as phone calls, the loss of a packet (about lms of data) may not result in a decrease in the user experience. However, this may not be the case when a key frame is lost. If a key frame is lost, then the receiving device may be unable to decode or decompress the received packet properly. All packets following the missing key frame may then be lost at the receiving device side until a new key frame is successfully received.

Consequently, the transmitting device may have to resend the key frame, which may take a substantial amount of time and may have a much larger size than a compressed frame. Practical tests have shown that in case of speech transmission, the feedback loop is of the order of about 100- 150ms. This is to say that when a key frame is lost, approximately 100-150ms of information may be lost. A loss of 100-150ms of information may severely degrade the user experience as the human threshold for noticeable loss may be significantly less than this amount.

[0080] For certain applications, the use of an uncompressed frame may lead to a large loss in terms of coverage. For a system with a low bandwidth, minimization of the number of uncompressed key frames sent may accordingly minimize the bandwidth requirement of a UE, with resultant gains in terms of complexity and battery life. Consequently, it may be desirable to prevent the loss of key frame during an over-the-air transmission as much as possible to retain the decoding and/or decompression capability at the receiving device side and avoid unnecessary transmission of new key frames.

[0081] To mitigate the transmission of new key frames, several actions may be taken by the transmitting and/or receiving device (e.g., UE, eNB). Note that the transmitting and receiving device may be of the same type, for example, both UEs in D2D communications, or may be different types. The transmitting device may detect the presence of a key frame. In some embodiments, the detection may be based on a notification from the protocol layer generating the key frame. In other embodiments, the detection may be based on packet inspection. In response to detection of the key frame, the system may increase protection of the transport block containing the key frame to reduce the loss of the key frame during the transmission over the air and minimize the use of uncompressed key frames.

[0082] A missing key frame may lead to transmission of a new key frame (for example uncompressed header in case of RoHC) which has a much larger size as normal frame and the receiving device dropping non-decodable/de- compressable data due to missing key frame. The radio resource usage efficiency may be improved by a reduction in the loss of decoding and/or decompression at the receiving device side due to minimization of missing key frames. This may lead to improved service (for instance better audio/video experience) and thus a better user experience.

[0083] FIG. 8 illustrates a flowchart of network communication in accordance with some embodiments. The operations shown in FIG. 8 may be performed by any of the devices shown in FIGS. 1-7. Some of the operations shown in FIG. 8 may not be performed, or other operations not shown may be performed in preventing the loss of key frames. Here, as throughout this description, the packets in each transport block may be generated and encoded by the transmitting device before being transmitted via one or more of the interfaces, and received at the receiving device via one or more of the interfaces interface and decoded by the receivmg device. [0084] At operation 802, the transmitting device (e.g., UE or eNB) may determine whether the frame to be transmitted is a key frame. In some embodiments, the detection of the key frame may be performed in the cellular protocol stack (CPS). In some embodiments, the detection of the key frame can be in the application layer or in the cellular protocol stack. Specifically, the key frame may be detected in the PDCP, RLC and/or MAC layer.

[0085] The detection of the key frame in operation 802 can be determined dependent on the transmitting device. Alternately, the detection of the key frame may be independent of the transmitting device; the same detection technique may be used. In some embodiments, an upper layer may convey an indication to the lower layers to identify key frames within the UE. In some embodiments, a flag may be added in the header to permit the lower layers to identify the presence of a key frame in the transport block. In some

embodiments, the layers may determine the presence of a particular detection partem that indicates the presence of a key frame in the transport block. The eNB may, for example, provide the detection pattern to the UE.

[0086] In some embodiments, the eNB may apply the same detection technique as in the UE - whether a flag is provided in one or more headers or a particular pattern is used. Alternatively, or in addition, when the eNB is the receiving device, the eNB may use dedicated information provided by the source eNB or UE. For instance, in FIG. 7, eNB2 704b may detect the key frame using information received from UE1 702a. Thus, for example, a flag can be appended in the MAC, RLC or PDCP header to indicate whether or not the packet contains a key frame. The indicator may be propagated between the protocol layers by an implementation-specific technique or a specific flag in the protocol header and the final eNB (e.g., eNB2 704b) could use this information to send the key packet to the final receiving device (e.g., UE2 702b) by means of techniques indicated below.

[0087] In some embodiments, the key frame may be identified through the use of a known header sequence or particular message type or field. For example, a detection pattern may be used in the CPS using packet inspection based on a detection filter based on a field of the protocol header or the payload if the protocol header or payload has a relevant parameter to identify the key frame. Thus, for example, the key frame may be identified through the use of a predetermined port number protocol type, IP address, or QoS setting in the header, or by the size of the header or of the packet (the header or packet length). The detection pattern may be configured by the network and notified to the UE in RRC or other control signaling.

[0088] In some embodiments, dedicated signaling between the transmitting device and the receiving device may be used to indicate which packet corresponds to a key frame. The dedicated signaling may be provided in advance of transmission of the key frame. For example, the UE may provide an indication of a key frame in a buffer status report (BSR) to the eNB. The dedicated signaling may be provided a predetermined amount of time prior to transmission of the key frame or may explicitly indicate in which resource block the key frame is to be transmitted.

[0089] For example, this may occur in a scheduled system in which the transmission parameter is dynamically configured by the eNB. When the UL resource is allocated by the eNB, the UE may inform the eNB about a key frame pending. This can be through a message or an extended scheduling request for an uplink grant of a key frame. The eNB can subsequently configure a UL grant with a lower MCS or with a bigger size so that the UE can add addition protection such as redundancy bits, for instance with the channel coder.

Alternatively, the UE may autonomously increase the protection, if resource can be preconfigured, or if the UE uses the available resource to better protect the key frame. In this latter case, the transmission of a normal frame may be postponed until after transmission of the key frame.

[0090] In some embodiments, detection of a key frame may be a combination of the above. This is to say that a key frame may be identified through a notification of the protocol layer generating the key frame to the cellular protocol stack using a dedicated message or using a new flag in a legacy protocol header. The message may be sent from one protocol layer to another in the transmitting device, or from the transmitting device to the receiving device. A legacy protocol header may be an existing header, e.g., already used in the LTE 4G or older system. In other embodiments, the protection may be applied by the transmitting device (e.g., UE) without an explicit indication being provided to the receiving device (e.g., eNB).

[0091] Once a key frame is identified, protective measures may be undertaken to provide protection to the transport blocks containing the key frame. As above, the protection provided to a key frame may not be provided to a normal frame (e.g., in addition to measures taken for a normal frame); that is, the protection applied to the transport blocks containing the key frame may be unavailable for transport blocks that contain a normal frame. At operation 804, the protective technique taken may be selected from one or more of a number of different techniques. The protective measures may be performed to increase the chance that the receiver can properly get the key frame. Thus, when a key frame is detected through the techniques indicated above and is to be sent over the air, it may be sent with increased protection.

[0092] The techniques to increase the protection may be classified into transparent techniques, in which specific receiver a priori knowledge may be irrelevant, and non-transparent techniques in which specific a priori knowledge of the receiving device may be used. Transparent protective techniques may include use of a lower modulation scheme/order than would otherwise be used. This is to say that while the modulation order is normally selected based on a measurement of the channel quality, the modulation order may be further lowered from the channel quality indicated value when a key frame is detected.

[0093] Another transparent protective technique may be to add redundancy to the information bits of the key frame. This may be performed, for instance, through the use of more robust channel coding. To increase the channel coding robustness, a lower coding rate may be selected for a particular modulation order than would otherwise be selected. This again may be based on a measurement of the channel quality, and the coding rate used may be lower than that indicated as desirable from the channel quality. In general, a lower modulation and coding scheme (MCS) index (modulation order and/or coding rate) may be used than that indicated by the channel conditions.

[0094] Alternatively, or in addition, the maximum number of retransmissions may be different between key frames and normal frames. This is to say that the maximum retransmission number may be larger for key frames in comparison to normal frames. Or, an increased number of repetitions may be configured if the key frame is transmitted in a PDSCH or PUSCH and the number of repetitions of the PDSCH or PUSCH carrying the key frame is based on Coverage Enhancement (CE) Mode A-based techniques. In other embodiments, the number of repetitions may be used in modes other than CE Mode A and/or may be dependent on the transmission mode. For example, or Cat Ml key frames may be allocated with more repetition (RLs) compared to normal frames even if the number of RLs allocated for the key frame is above the maximum available resources within a connected discontinuous reception (CDRX) cycle. For example, a CDRX mode may have a cycle time of 20ms, 16 RL may be allocated for normal frames to enable the next packet to be received. Assuming that the maximum acceptable delay is 40-50ms, the key frame may instead be allocated with, e.g. 32RL. While this may lead to the next normal speech packet being lost, the key frame may be protected.

[0095] As is apparent, transparent techniques may be used independent of knowledge of whether the packet is a key frame or a normal frame. Thus, when the UE receives a key frame with additional protection, the DCI may indicate the MCS used, or the redundancy version (RV) used. When using transparent techniques, handling in the receiving device may be independent of specific knowledge of the frame (whether normal or key).

[0096] On the other hand, non-transparent techniques that employ a priori knowledge may be used by the receiving device. Such techniques may include the use of a concatenation of the channel coding schemes to increase protection, e.g., by using serial concatenations of classical channel coding techniques, such as turbo coding). In some embodiments, the same channel coding structure as in legacy schemes can be used to reuse transport blocks that are already in both the transmitting and the receiving device. The reliability may be increased as the coding rate is decreased. The same or different coding rates may be used. For example, a serial concatenation of two turbo codes with different coding rates (a coding rate tailored depending on the channel conditions and desired reliability) may be used. Such a technique may, however, cause the receiving device to decode the packets the multiple of the serial concatenation (e.g., if two codes are used, the receiving device may decode twice as many packets with the same information compared to a single transmission). The use of code concatenation may allow a further reduction in the coding rate.

[0097] Once the desired type of protection is selected (transparent and/or non-transparent), at operation 806, the protection technique may be applied to the key frame. In some embodiments, a single protection technique may be selected, while in other embodiments, multiple transparent and/or non- transparent protection techniques may be used. In the latter case, for example, the MCS may be reduced and the maximum number of retransmissions increased. In some embodiments, the same protection technique may be used independent of the content of the key frame. In other embodiments, the protection technique used may be dependent on the content of the key frame - for example, use of a lower MCS (modulation order and/or coding scheme) for video content and maximum retransmission or RL increase for voice content. In some embodiments, the protection technique used may be dependent on the channel conditions. For example, if the channel is severely degraded, the transmitting device may forego the use of a lower MCS (if a lower MCS is even available) to increase the maximum retransmission or RL.

[0098] At operation 808, the key frame may be transmitted with the selected protection technique(s) in place. The transmission may be based on an eNB allocation. The eNB may control the radio resource allocation and may directly apply the protection when a key frame is to be sent according to the techniques described above. The protection can also be enabled by the eNB when providing the scheduling information to the UE, with or without providing explicit information on whether a more robust protection is used (understanding that this would be up to network decision).

[0099] When a priori information is used by the receiving device for key frame protection, the eNB may in some embodiments indicate to the UE the presence of a key frame with extra protection via the DCI. The DCI may contain additional information about the MCS applied. In UL, the eNB may modify the decoding process by decoding the key frame packet multiple times.

[00100] In some embodiments, the UL grant may indicate additional protection methods are to be used. In LTE networks, the eNB may provide the UE with uplink resources allocated for the PUSCH. The UE may then notify the eNB in advance the presence of a key frame waiting for transmission to receive an UL grant with addition protection. This additional protection may include one or more of lower MCS, additional RL, or extra coding. The UE can notify the eNB using an extension of the BSR, as above, or using a Data Volume indication or a legacy MAC control element (with a new field) or new MAC control element. The UE may indicate the size of the key frame to help the eNB to allocate the appropriate resource. In some embodiments, if multiple key frames are to be sent, the UE may notify the eNB when a key frame is present and then notify the eNB when all key frame have been transmitted. Thus, use of a resource request for each key frame may be avoided.

[00101] In some embodiments, only a flag may be set by the UE to the eNB to indicate whether the next grant should be provided with additional robustness. Alternatively, the flag can be maintained while key frames are still buffered. Moreover, a new scheduling request may be defined for a UE to request UL grant with more robustness, or to request periodic robustness UL grants or with specific pattern. For the case when specific patterns are used, a new semi-persistent UL grant allocation may be defined to accommodate different configurations with different robustness. Upon reception of the UL grant with increased protection, the UE may send the key frame over the air as indicated in operation 808. [00102] The UE may detect that the received UL grant is a "special protected" grant in response the UE request. Note that one or more normal grants may be received in between the request and reception of the special protected grant. As above, a new DCI format may be introduced to indicate the special protected grant. Alternatively, a new information bit in a legacy DCI format may be provided to indicate the special protected grant.

[00103] Thus, in some embodiments, when the transmitting device is a

UE, the information used to decode the key frame in the eNB may be transmitted in the DCI; that is, the eNB may provide the parameters the UE is to use to encode the data. In some embodiments, the DCI may contain additional parameters that correspond to one or more of the presence of a key frame, whether the key frame is to be encoded in a non-transparent manner, or the coding rate to be used, among others.

[00104] Internal detection within a UE having the PHY layer may notify the MAC layer about parameters such as MCS, RL ... ). The MAC layer can then decide if the protection is sufficient to transmit the key frame. If the protection is insufficient, the UE may determine whether the key frame is to be transmitted and take appropriate action thereon. In some embodiments, the UE may re-request sufficient allocation for the key frame to be transmitted; in other embodiment, the UE may transmit the key frame using the allocation provided by the eNB, irrespective of the desired allocation. Whether or not the key frame is transmitted may depend, for example, on the difference between the desired allocation and the actual allocation, the channel conditions and/or the content of the key frame. Scheduling techniques used by the eNB may also avoid confusion when the received UL grant is the "special protected" grant. This may be a potental issue for low bandwidth configurations, such as when the UE is an Intemet-of-things (IOT) device.

[00105] Examples

[00106] Example 1 is an apparatus of a user equipment (UE), the apparatus comprising: an interface to communicate with an evolved NodeB (eNB); and processing circuitry in communication with the interface and arranged to: detect whether transport blocks to be transmitted from the UE contain a key frame; and apply reliability protection for the transport blocks that contain the key frame in response to a determination that the key frame is to be transmitted from the UE, the reliability protection available for transmission of the transport blocks that contain the key frame and unavailable for transmission of transport blocks that contain a normal frame, the reliability protection configured to enhance reliability of reception of the key frame at the eNB.

[00107] In Example 2, the subject matter of Example 1 includes, wherein: the key frame is detected in an application layer or in a cellular protocol stack.

[00108] In Example 3, the subj ect matter of Example 2 includes, wherein: to detect whether the transport blocks contain the key frame, the processing circuitry is configured to use packet inspection of a field of protocol header or a payload.

[00109] In Example 4, the subject matter of Example 3 includes, wherein the processing circuitry is configured to: identify the presence of the key frame through use of at least one of a predetermined port number, protocol type, Internet Protocol (IP) address, Quality of Service (QoS) setting, or header length in the protocol header, or packet length.

[00110] In Example 5, the subject matter of Examples 3-4 includes, wherein: to detect whether the transport blocks contain the key frame, the processing circuitry is configured to use a flag in the protocol header, the protocol header being a legacy protocol header.

[00111] In Example 6, the subject matter of Examples 3-5 includes, wherein the processing circuitry is further configured to: identify presence of the key frame by a size of the payload.

[00112] In Example 7, the subject matter of Examples 3-6 includes, wherein: to detect whether the transport blocks contain the key frame, the processing circuitry is configured to use a message transmitted from a medium access control (MAC) layer to a physical (PHY) layer. [00113] In Example 8, the subject matter of Examples 1-7 includes, wherein: the reliability protection is applied free from an explicit indication of the key frame in the transport blocks being provided to the eNB.

[00114] In Example 9, the subject matter of Examples 1-8 includes, wherein: the reliability protection comprises selection of a lower modulation and coding scheme (MCS) index than that indicated by channel conditions and used by transport blocks containing the normal frame.

[00115] In Example 10, the subject matter of Examples 1-9 includes, wherein: the reliability protection comprises an increase in a number of maximum retransmissions of the transport blocks that contain the key frame.

[00116] In Example 1 1, the subject matter of Examples 1-10 includes, wherein: the processing circuitry is further configured to encode, for transmission to the eNB via the interface, the transport blocks that contain the key frame, and a number of repetitions for the transport blocks that contain the key frame is increased compared to the transport blocks that contain the normal frame.

[00117] In Example 12, the subject matter of Examples 1-11 includes, wherein: the reliability protection is indicated in Downlink Control Information (DCI).

[00118] In Example 13, the subject matter of Example 12 includes, wherein: the DCI contains parameters that correspond to one or more of: the presence of the key frame, whether the key frame is to be encoded in a transparent or non-transparent manner, or which reliability protection to use from a plurality of different types of reliability protection.

[00119] In Example 14, the subject matter of Examples 1-13 includes, wherein the processing circuitry is further configured to: encode, for transmission to the eNB via the interface, signaling separate from the transport blocks, the signaling comprising an explicit indication of the key frame in the transport blocks.

[00120] In Example 15, the subject matter of Example 14 includes, wherein the processing circuitry is further configured to: decode, in response to transmission of the signaling, an uplink grant for transmission of the key frame, the uplink grant comprising increased allocation for the transmission of the key frame compared with transmission of a normal frame.

[00121] In Example 16, the subject matter of Example 15 includes, wherein: the signaling comprises at least one of a buffer status report, a data volume indication or a medium access control (MAC) Control Element.

[00122] In Example 17, the subject matter of Examples 15-16 includes, wherein: the signaling indicates a size of a packet to be transmitted, the size configured to provide the indication.

[00123] In Example 18, the subject matter of Examples 15-17 includes, wherein: the signaling comprises a flag to indicate that a next uplink grant is to be allocated with additional resources.

[00124] In Example 19, the subject matter of Examples 1-18 includes, wherein the processing circuitry is further configured to: encode for transmission to the eNB via the interface, a scheduling request for a normal frame uplink grant of a normal frame, decode the normal frame uplink grant, encode for transmission to the eNB via the interface, after reception of the normal frame uplink grant, an extended scheduling request for a key frame uplink grant with increased robustness for transmission of the key frame compared to robustness of the normal frame uplink grant, the scheduling request selected via a semi- persistent uplink grant allocation that accommodates different configurations with different robustness, and decode the key frame uplink grant.

[00125] In Example 20, the subject matter of Examples 1-19 includes, wherein the processing circuitry is further configured to: encode for transmission to the eNB via the interface, a scheduling request for a normal frame uplink grant of a normal frame, decode the normal frame uplink grant, determine whether the normal frame uplink grant is sufficient for transmission of the key frame; and in response to a determination that the normal frame uplink grant is insufficient for transmission of the key frame, take an action dependent on at least one of: a difference between the normal frame uplink grant and a key frame uplink grant sufficient for transmission of the key frame, channel conditions, or content of the key frame.

[00126] In Example 21, the subject matter of Examples 1-20 includes, wherein: the processing circuitry comprises a baseband processor configured to encode transmissions to, and decode transmissions from, the eNB.

[00127] Example 22 is an apparatus of an evolved NodeB (eNB), the apparatus comprising: an interface to communicate with a user equipment (UE); and detect whether transport blocks to be transmitted from the UE contain a key frame; encode, for transmission to the UE via the interface in response to a scheduling request from the UE and a determination that the key frame is to be transmitted from the UE, a key frame uplink grant for transmission of the key frame; and decode the transport blocks transmitted by the UE with reliability protection unavailable for transport blocks that contain a normal frame, the reliability protection configured to enhance reliability of reception of the key frame at the eNB.

[00128] In Example 23, the subject matter of Example 22 includes, wherein: to detect whether the transport blocks contain the key frame, the processing circuitry is configured to use packet inspection from a field of protocol header.

[00129] In Example 24, the subject matter of Example 23 includes, wherein the processing circuitry is configured to: identify the key frame through use of a flag in the protocol header, the protocol header selected from a legacy medium access control (MAC), radio link control (RLC) or packet data convergence protocol (PDCP) header.

[00130] In Example 25, the subject matter of Examples 22-24 includes, wherein the processing circuitry is configured to: identify presence of the key frame by a size of a payload.

[00131] In Example 26, the subject matter of Examples 22-25 includes, wherein the processing circuitry is configured to: to detect whether the transport blocks contain the key frame, the processing circuitry is configured to detect signaling from the UE that is separate from the scheduling request, the signaling comprising at least one of a buffer status report, a data volume indication or a medium access control (MAC) Control Element.

[00132] In Example 27, the subject matter of Examples 22-26 includes, wherein the transport blocks that contain the key frame are transmitted at least one of: at a modulation scheme configured for key frames, at a coding rate configured for key frames, having a number of maximum retransmissions configured for key frames, or having a number of repetitions configured for key frames when coverage enhancement mode A is used.

[00133] In Example 28, the subject matter of Examples 22-27 includes, wherein: the key frame uplink grant is configured to provide increased robustness for transmission of the key frame compared to robustness of an uplink grant for transmission of a normal frame.

[00134] Example 29 is a computer-readable storage medium that stores instructions for execution by one or more processors of a user equipment (UE), the one or more processors to configure the UE to: detect whether transport blocks to be transmitted from the UE contain a key frame, the detection based on one of: packet inspection of a field of protocol header or payload, a size of the payload, or a message transmitted between protocol layers; apply reliability protection to the transport blocks that contain the key frame, the reliability protection configured to enhance reliability of reception of the key frame at the eNB, the reliability protection selected from one or more of: a modulation scheme dependent on a type of frame, a coding rate dependent on the type of frame, or a number of maximum retransmissions dependent on the type of frame; and transmit the transport blocks that contain the key frame using the applied reliability protection.

[00135] In Example 30, the subject matter of Example 29 includes, wherein at least one of: Downlink Control Information (DCI) contains parameters that correspond to one or more of whether the key frame is to be encoded in a transparent or non-transparent manner, or reliability protection to use when the transport blocks that contain the key frame is to be transmitted, the UE is configured to provide to an evolved NodeB (eNB) an indication of the key frame in one or more of a buffer status report, a data volume indication or a medium access control (MAC) Control Element, or the UE is configured to receive, in response to an extended scheduling request transmitted to the eNB after reception of a normal frame uplink grant for transmission of a normal frame, a key frame uplink grant that provides increased robustness for transmission of the key frame compared to robustness of the normal frame uplink grant.

[00136] Example 31 is a method of protecting a key frame of a User

Equipment (UE), the method comprising: detecting whether transport blocks to be transmitted from the UE contain a key frame, the detection based on one of: packet inspection of a field of protocol header or payload, a size of the payload, or a message transmitted between protocol layers; applying reliability protection to the transport blocks that contain the key frame, the reliability protection configured to enhance reliability of reception of the key frame at the eNB, the reliability protection selected from one or more of: a modulation scheme dependent on a type of frame, a coding rate dependent on the type of frame, or a number of maximum retransmissions dependent on the type of frame; and transmitting the transport blocks that contain the key frame using the applied reliability protection.

[00137] In Example 32, the subject matter of Example 31 includes, wherein at least one of: Downlink Control Information (DCI) contains parameters that correspond to one or more of whether the key frame is to be encoded in a transparent or non-transparent manner, or reliability protection to use when the transport blocks that contain the key frame is to be transmitted, the UE is configured to provide to an evolved NodeB (eNB) an indication of the key frame in one or more of a buffer status report, a data volume indication or a medium access control (MAC) Control Element, or the UE is configured to receive, in response to an extended scheduling request transmitted to the eNB after reception of a normal frame uplink grant for transmission of a normal frame, a key frame uplink grant that provides increased robustness for transmission of the key frame compared to robustness of the normal frame uplink grant.

[00138] Example 33 is an apparatus of a User Equipment (UE), the apparatus comprising: means of detecting whether transport blocks to be transmitted from the UE contain a key frame, the detection based on one of: packet inspection of a field of protocol header or payload, a size of the payload, or a message transmitted between protocol layers; means of applying reliability protection to the transport blocks that contain the key frame, the reliability protection configured to enhance reliability of reception of the key frame at the eNB, the reliability protection selected from one or more of: a modulation scheme dependent on a type of frame, a coding rate dependent on the type of frame, or a number of maximum retransmissions dependent on the type of frame; and means of transmitting the transport blocks that contain the key frame using the applied reliability protection.

[00139] In Example 34, the subject matter of Example 33 includes, wherein at least one of: Downlink Control Information (DCI) contains parameters that correspond to one or more of whether the key frame is to be encoded in a transparent or non-transparent manner, or reliability protection to use when the transport blocks that contain the key frame is to be transmitted, the UE is configured to provide to an evolved NodeB (eNB) an indication of the key frame in one or more of a buffer status report, a data volume indication or a medium access control (MAC) Control Element, or the UE is configured to receive, in response to an extended scheduling request transmitted to the eNB after reception of a normal frame uplink grant for transmission of a normal frame, a key frame uplink grant that provides increased robustness for transmission of the key frame compared to robustness of the normal frame uplink grant.

[00140] Example 35 is at least one machine-readable medium including instructions that, when executed by processing circuitry, cause the processing circuitry to perform operations to implement of any of Examples 1-34. [00141] Example 36 is an apparatus comprising means to implement of any of Examples 1-34.

[00142] Example 37 is a system to implement of any of Examples 1-34.

[00143] Example 38 is a method to implement of any of Examples 1-34.

[00144] Although an embodiment has been described with reference to specific example embodiments, it will be evident that various modifications and changes may be made to these embodiments without departing from the broader scope of the present disclosure. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense. The

accompanying drawings that form a part hereof show, by way of illustration, and not of limitation, specific embodiments in which the subject matter may be practiced. The embodiments illustrated are described in sufficient detail to enable those skilled in the art to practice the teachings disclosed herein. Other embodiments may be utilized and derived therefrom, such that structural and logical substitutions and changes may be made without departing from the scope of this disclosure. This Detailed Description, therefore, is not to be taken in a limiting sense, and the scope of various embodiments is defined only by the appended claims, along with the full range of equivalents to which such claims are entitled.

[00145] The subject matter may be referred to herein, individually and/or collectively, by the term "embodiment" merely for convenience and without intending to voluntarily limit the scope of this application to any single inventive concept if more than one is in fact disclosed. Thus, although specific embodiments have been illustrated and described herein, it should be appreciated that any arrangement calculated to achieve the same purpose may be substituted for the specific embodiments shown. This disclosure is intended to cover any and all adaptations or variations of various embodiments. Combinations of the above embodiments, and other embodiments not specifically described herein, will be apparent to those of skill in the art upon reviewing the above description.

[00146] In this document, the terms "a" or "an" are used, as is common in patent documents, to include one or more than one, independent of any other instances or usages of "at least one" or "one or more." In this document, the term "or" is used to refer to a nonexclusive or, such that "A or B" includes "A but not B," "B but not A," and "A and B," unless otherwise indicated. In this document, the terms "including" and "in which" are used as the plain-English equivalents of the respective terms "comprising" and "wherein." Also, in the following claims, the terms "including" and "comprising" are open-ended, that is, a system, UE, article, composition, formulation, or process that includes elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim. Moreover, in the following claims, the terms "first," "second," and "third," etc. are used merely as labels, and are not intended to impose numerical requirements on their objects.

[00147] The Abstract of the Disclosure is provided to comply with 37

C.F.R. §1.72(b), requiring an abstract that will allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, it can be seen that various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment.

Claims

CLAIMS What is claimed is:

1. An apparatus of a user equipment (UE), the apparatus comprising:

an interface to communicate with an evolved NodeB (eNB); and processing circuitry in communication with the interface and arranged to: detect whether transport blocks to be transmitted from the UE contain a key frame; and

apply reliability protection for the transport blocks that contain the key frame in response to a determination that the key frame is to be transmitted from the UE, the reliability protection available for transmission of the transport blocks that contain the key frame and unavailable for transmission of transport blocks that contain a normal frame, the reliability protection configured to enhance reliability of reception of the key frame at the eNB.

2. The apparatus of claim 1 , wherein:

the key frame is detected in an application layer or in a cellular protocol stack.

3. The apparatus of claim 2, wherein:

to detect whether the transport blocks contain the key frame, the processing circuitry is configured to use packet inspection of a field of protocol header or a payload.

4. The apparatus of claim 3, wherein the processing circuitry is configured to:

identify the presence of the key frame through use of at least one of a predetermined port number, protocol type, Internet Protocol (IP) address, Quality of Service (QoS) setting, or header length in the protocol header, or packet length.

5. The apparatus of claim 3, wherein:

to detect whether the transport blocks contain the key frame, the processing circuitry is configured to use a flag in the protocol header, the protocol header being a legacy protocol header.

6. The apparatus of claim 3, wherein the processing circuitry is further configured to:

identify presence of the key frame by a size of the payload.

7. The apparatus of claim 3, wherein:

to detect whether the transport blocks contain the key frame, the processing circuitry is configured to use a message transmitted from a medium access control (MAC) layer to a physical (PHY) layer.

8. The apparatus of any one or more of claims 1-7, wherein:

the reliability protection is applied free from an explicit indication of the key frame in the transport blocks being provided to the eNB.

9. The apparatus of any one or more of claims 1-7, wherein:

the reliability protection comprises selection of a lower modulation and coding scheme (MCS) index than that indicated by channel conditions and used by transport blocks containing the normal frame.

10. The apparatus of any one or more of claims 1-7, wherein:

the reliability protection comprises an increase in a number of maximum retransmissions of the transport blocks that contain the key frame.

11. The apparatus of any one or more of claims 1-7, wherein:

the processing circuitry is further configured to encode, for transmission to the eNB via the interface, the transport blocks that contain the key frame, and a number of repetitions for the transport blocks that contain the key is increased compared to the transport blocks that contain the normal

The apparatus of any one or more of claims 1 -7, wherein:

the reliability protection is indicated in Downlink Control Information

The apparatus of claim 12, wherein:

the DCI contains parameters that correspond to one or more of:

the presence of the key frame,

whether the key frame is to be encoded in a transparent or non transparent manner, or

which reliability protection to use from a plurality of different types of reliability protection.

14. The apparatus of any one or more of claims 1 -7, wherein the processing circuitry is further configured to:

encode, for transmission to the eNB via the interface, signaling separate from the transport blocks, the signaling comprising an explicit indication of the key frame in the transport blocks.

15. The apparatus of claim 14, wherein the processing circuitry is further configured to:

decode, in response to transmission of the signaling, an uplink grant for transmission of the key frame, the uplink grant comprising increased allocation for the transmission of the key frame compared with transmission of a normal frame.

The apparatus of claim 15, wherein: the signaling comprises at least one of a buffer status report, a data volume indication or a medium access control (MAC) Control Element.

17. The apparatus of claim 15, wherein:

the signaling indicates a size of a packet to be transmitted, the size configured to provide the indication.

18. The apparatus of claim 15, wherein:

the signaling comprises a flag to indicate that a next uplink grant is to be allocated with additional resources.

19. The apparatus of any one or more of claims 1 -7, wherein the processing circuitry is further configured to:

encode for transmission to the eNB via the interface, a scheduling request for a normal frame uplink grant of a normal frame,

decode the normal frame uplink grant,

encode for transmission to the eNB via the interface, after reception of the normal frame uplink grant, an extended scheduling request for a key frame uplink grant with increased robustness for transmission of the key frame compared to robustness of the normal frame uplink grant, the scheduling request selected via a semi-persistent uplink grant allocation that accommodates different configurations with different robustness, and

decode the key frame uplink grant.

20. The apparatus of any one or more of claims 1 -7, wherein the processing circuitry is further configured to:

decode the normal frame uplink grant,

determine whether the normal frame uplink grant is sufficient for transmission of the key frame; and in response to a determination that the normal frame uplink grant is insufficient for transmission of the key frame, take an action dependent on at least one of:

a difference between the normal frame uplink grant and a key frame uplink grant sufficient for transmission of the key frame,

channel conditions, or

content of the key frame.

21. The apparatus of any one or more of claims 1 -7, wherein:

the processing circuitry comprises a baseband processor configured to encode transmissions to, and decode transmissions from, the eNB.

22. An apparatus of an evolved NodeB (eNB), the apparatus comprising: an interface to communicate with a user equipment (UE); and

detect whether transport blocks to be transmitted from the UE contain a key frame;

encode, for transmission to the UE via the interface in response to a scheduling request from the UE and a determination that the key frame is to be transmitted from the UE, a key frame uplink grant for transmission of the key frame; and

decode the transport blocks transmitted by the UE with reliability protection unavailable for transport blocks that contain a normal frame, the reliability protection configured to enhance reliability of reception of the key frame at the eNB.

23. The apparatus of claim 22, wherein:

to detect whether the transport blocks contain the key frame, the processing circuitry is configured to use packet inspection from a field of protocol header.

24. The apparatus of claim 23, wherein the processing circuitry is configured to:

identify the key frame through use of a flag in the protocol header, the protocol header selected from a legacy medium access control (MAC), radio link control (RLC) or packet data convergence protocol (PDCP) header.

25. The apparatus of claim 22, wherein the processing circuitry is configured to:

identify presence of the key frame by a size of a payload.

26. The apparatus of any one or more of claims 22-25, wherein the processing circuitry is configured to:

to detect whether the transport blocks contain the key frame, the processing circuitry is configured to detect signaling from the UE that is separate from the scheduling request, the signaling comprising at l east one of a buffer status report, a data volume indication or a medium access control (MAC) Control Element.

27. The apparatus of any one or more of claims 22-25, wherein the transport blocks that contain the key frame are transmitted at least one of:

at a modulation scheme configured for key frames,

at a coding rate configured for key frames,

having a number of maximum retransmissions configured for key frames, or

having a number of repetitions configured for key frames when coverage enhancement mode A is used.

28. The apparatus of any one or more of claims 22-25, wherein:

the key frame uplink grant is configured to provide increased robustness for transmission of the key frame compared to robustness of an uplink grant for transmission of a normal frame.

29. A computer-readable storage medium that stores instructions for execution by one or more processors of a user equipment (UE), the one or more processors to configure the UE to:

detect whether transport blocks to be transmitted from the UE contain a key frame, the detection based on one of:

packet inspection of a field of protocol header or payload, a size of the payload, or

a message transmitted between protocol layers;

apply reliability protection to the transport blocks that contain the key frame, the reliability protection configured to enhance reliability of reception of the key frame at the eNB, the reliability protection selected from one or more of:

a modulation scheme dependent on a type of frame, a coding rate dependent on the type of frame, or

a number of maximum retransmissions dependent on the type of frame; and

transmit the transport blocks that contain the key frame using the applied reliability protection.

30. The medium of claim 29, wherein at least one of:

Downlink Control Information (DO) contains parameters that correspond to one or more of whether the key frame is to be encoded in a transparent or non-transparent manner, or reliability protection to use when the transport blocks that contain the key frame is to be transmitted,

the UE is configured to provide to an evolved NodeB (eNB) an indication of the key frame in one or more of a buffer status report, a data volume indication or a medium access control (MAC) Control Element, or the UE is configured to receive, in response to an extended scheduling request transmitted to the eNB after reception of a normal frame uplink grant for transmission of a normal frame, a key frame uplink grant that provides increased robustness for transmission of the key frame compared to robustness of the normal frame uplink grant.