Abstract: Enhanced random access procedures for link-budget-limited user equipment (UE) devices are disclosed. A user equipment device may transmit a first message containing a Physical Random Access Channel (PRACH). The PRACH contains instances of a Zadoff-Chu sequence, and may be transmitted repeatedly as part of a single random attempt, to facilitate correlation data combining at the base station. The available Zadoff-Chu sequences may be partitioned among a plurality of sets, each set being associated with a respective Doppler shift range (or frequency hop pattern or time repetition pattern). A UE device may signal Doppler shift (or other information) to the base station by selection of one of the sets. The first PRACH transmission and the following PRACH transmission may occur in consecutive subframes. A UE device may select from a special set of Zadoff-Chu sequences (different from a conventional set of sequences), to signal its status as a link-budget-limited device.

Abstract: Systems, methods, and devices are provided for reducing and/or eliminating impact of inter-carrier interference on wireless signals transmitted and received via off-grid radio communications (e.g., Device-to-Device (D2D) communication). The method may include using circuitry to generate a plurality of subcarriers associated with a data signal, such that the plurality of subcarriers transmit the data signal along a narrowband transmission channel. The method may involve using the circuitry to remove a null subcarrier of the plurality of subcarriers that is located at a direct current (DC) frequency. The method may also involve generating an asymmetrical frequency spectrum for a portion of the plurality of subcarriers centered about the removed null subcarrier. The method may also include transmitting the plurality of subcarriers to another electronic device via D2D communication.

Abstract: A user equipment (UE) device may communicate according to a new device category satisfying specified QoS (quality of service) requirements while also satisfying specified link budget requirements, and additional optimization requirements. The new device category may identify the UE device as a wearable device. According to some embodiments, LTE category M may be extended to support non-MTC operations performed by wearable devices. For example, the new device category may support UE mobility and may disallow access barring. Additional extensions may be implemented in response to an indication by the UE that the UE is implementing a specific application, such as VoLTE or a near real-time application, such as audio streaming. In some scenarios, the indication may include the UE indicating a specific QCI value. In some scenarios, the indication may include the UE attaching to a specific APN.

Abstract: This disclosure relates to providing system information for cell access to link budget limited devices. According to some embodiments, a base station may transmit an announcement information block (MB) in a downlink shared data channel (e.g., PDSCH), wherein the AIB contains information useable by a UE in determining the location of system information in the downlink shared data channel. The UE can thus determine the location of and decode system information without having to decode a downlink control channel (e.g., PDCCH). This may be important for certain classes of devices, such as link budget limited devices, which have issues in decoding the downlink control channel. Improved paging scheduling techniques are also disclosed which more efficiently use PDCCH paging resources.

Abstract: This disclosure relates to techniques for a link budget limited UE to improve communications performance with a cellular network. The UE may perform signal to interference noise ratio (SINR) measurements and use these measurements to adjust a received signal power value that is provided to the cellular network as a received signal power measurement. The UE may generate the received signal power value based at least in part on the SINR measurement in order to reduce the likelihood of handover when the UE has good SINR but poor received signal power. The UE may also provide preferred configuration information to the base station which enhances the performance of the UE when link budget limited. The configuration information may specify one or more parameter values designed to provide improved performance for a link budget limited device.

Abstract: This disclosure relates to TTI bundling for downlink communication. According to one embodiment, a base station and a wireless device may establish a wireless communication link. The base station may determine to enable TTI bundling for downlink communication for at least one carrier of the wireless communication link. The base station may provide an indication to the wireless device to enable TTI bundling for downlink communication for the determined carrier(s) of the wireless communication link. The base station may subsequently transmit TTI bundle downlink communications to the wireless device via the determined carrier(s).

Abstract: This disclosure relates to techniques for supporting narrowband device-to-device wireless communication, including possible techniques for performing discovery in an off grid radio system. A wireless device may obtain synchronization with a peer-to-peer communication group. The wireless device may determine the location of the wireless device within the peer-to-peer communication group based at least in part on signal strength of a synchronization signal used to obtain the synchronization. The wireless device may perform peer-to-peer discovery in the peer-to-peer communication group, such that time and frequency resources used by the wireless device to perform the peer-to-peer discovery are determined based at least in part on the location of the first wireless device within the peer-to-peer communication group.

Abstract: This disclosure relates to performing cellular communication in unlicensed spectrum in a manner that accounts for the possible existence of hidden nodes by opportunistically introducing the use of RTS and CTS messages. A listen-before-talk procedure may be performed to determine whether a wireless medium is available. When the listen-before-talk procedure is complete, an amount of time until a next possible start time for communicating in the cellular communication system according to a timing synchronization scheme for the cellular communication system may be determined. The wireless medium may be occupied until the next possible start time for communicating in the cellular communication system in a manner selected based at least in part on the amount of time until the next possible start time for communicating in the cellular communication system. Cellular communication may be performed on the wireless medium at the next possible start time for communicating in the cellular communication system.

Abstract: The disclosure describes procedures for allocating network resources for a mobile device communicating within a Long Term Evolution (LTE) network. The mobile device can be configured to decode a physical downlink shared channel (PDSCH), acquire first and second physical downlink control channel (PDCCH) decode indicators from a payload of the same PDSCH communication, decode a PDCCH for downlink control information (DCI) associated with a first application data type based on the first PDCCH decode indicator a second application data type based on the second PDCCH decode indicator. The first PDCCH decode indicator can identify an upcoming LTE subframe where the mobile device is required to decode the PDCCH for DCI associated VoLTE resource assignments and the second PDCCH decode indicator can identify an upcoming LTE subframe where the mobile device is required to decode the PDCCH for DCI associated with high bandwidth best effort (BE) data resource assignments.

Abstract: Distributing indications of emergency messages via Wi-Fi. A cellular device may temporarily disable its cellular modem. The cellular device may receive an indication over Wi-Fi that an emergency message has been broadcast. In response, the cellular device may activate its cellular modem and retrieve the emergency message via a cellular network.

Abstract: A link-budget-limited wireless communication device (UE) may implement improved radio link monitoring procedures for enhancing the link-budget of the UE. The UE may monitor the radio link and may determine whether the radio link can support a lowest acceptable link quality according to a hysteresis-based comparison that uses threshold values to determine error rates associated with a physical control channel. The UE may also identify itself to the network as a link-budget-limited device, and the network may enable special link-budget enhancing features for the UE, including boosting the power of the resource elements (REs) carrying physical channel signaling/data to the UE. The UE may detect the presence of power boost and may estimate/determine the power boost level.

Abstract: A wireless communication device may conduct first wireless communications over a first frequency band according to a first radio access technology (RAT), and may detect second wireless communications conducted over the first frequency band according to a second RAT while the wireless communication device is conducting the first wireless communications. The wireless communication device may then adjust characteristics and/or parameters associated with the first wireless communications based on the detected second wireless communications. In a specific example, a wireless communication device conducting Wi-Fi communications in the 5 GHz band may detect cellular communications (e.g. LAA/LTE-U communications) also conducted in the 5 GHz band while the wireless communication device is conducting the Wi Fi communications.

Abstract: In at least some embodiments, a method, apparatus, and system for performing communication using a plurality of radio access technologies (RATs) including a cellular RAT and a short-range RAT. A mobile device may be configured to receive information regarding traffic steering, i.e., cellular/short-range RAT handover, from nearby short-range access points and/or from a cellular base station. The mobile device may generate or determine mobility information of the mobile device, which indicates an amount of movement of the mobile device. The mobile device may determine whether the mobile device should transition between the cellular RAT and the short-range RAT based at least in part on the traffic-steering information and the mobility information. The mobile device may selectively transition between the cellular RAT and the short-range RAT based on the determination.

Abstract: In a method of device-to-device communication, a user device initially sends an emergency message repeatedly at a first repeating frequency. When a specified number acknowledgement (ACK) messages are received, the user device sends the emergency message repeatedly at a reduced repeating frequency. The repeating frequency may be further reduced when more ACK messages are received.

Abstract: A power control method for device-to-device communication includes dynamically backing off transmit power value for synchronization signals and discovery messages when the distance between the two devices is less than a pre-determined threshold. The threshold distance may correspond to a distance where the receive power may exceed a pre-determined value. Embodiments may loop the transmit power of synchronization signals between a default transmit power value and backed-off values in consecutive slots of each frame.

Abstract: In a method of device-to-device communication, efficient power management is provided when a primary device has a low battery level. The primary device can send synchronization signals and discovery messages to secondary devices by looping through a sequence of transmit power values in a sequence of consecutive frames, where the sequence of transmitting values includes a default power value and a reduced power value.

Abstract: Systems, methods, and devices are provided for reducing and/or eliminating impact of inter-carrier interference on wireless signals transmitted and received via off-grid radio communications (e.g., Device-to-Device (D2D) communication). The method may include using circuitry to generate a plurality of subcarriers associated with a data signal, such that the plurality of subcarriers transmit the data signal along a narrowband transmission channel. The method may involve using the circuitry to remove a null subcarrier of the plurality of subcarriers that is located at a direct current (DC) frequency. The method may also involve generating an asymmetrical frequency spectrum for a portion of the plurality of subcarriers centered about the removed null subcarrier. The method may also include transmitting the plurality of subcarriers to another electronic device via D2D communication.

Abstract: This disclosure relates to techniques for supporting asymmetric uplink and downlink bandwidth allocations for a wireless device, and for dynamically modifying the bandwidth allocations for a wireless device, in a wireless communication system. A cellular communication link may be established between a base station and a wireless device. The base station may determine an uplink bandwidth allocation and a downlink bandwidth allocation for the wireless device. The uplink bandwidth allocation and the downlink bandwidth allocation may be selected based on different criteria and may include different amounts of bandwidth. Indications of the uplink bandwidth allocation and the downlink bandwidth allocation may be provided to the wireless device. The base station and wireless device may communicate according to the uplink bandwidth allocation and the downlink bandwidth allocation.

Abstract: In a method of device-to-device communication, efficient power management is provided when a primary device has a low battery level. The primary device can send synchronization signals and discovery messages to secondary devices by looping through a sequence of transmit power values in a sequence of consecutive frames, where the sequence of transmitting values includes a default power value and a reduced power value.

Abstract: Enhanced random access procedures for link-budget-limited user equipment (UE) devices are disclosed. A user equipment device may transmit a first message containing a Physical Random Access Channel (PRACH). The PRACH contains instances of a Zadoff-Chu sequence, and may be transmitted repeatedly as part of a single random attempt, to facilitate correlation data combining at the base station. The available Zadoff-Chu sequences may be partitioned among a plurality of sets, each set being associated with a respective Doppler shift range (or frequency hop pattern or time repetition pattern). A UE device may signal Doppler shift (or other information) to the base station by selection of one of the sets. The first PRACH transmission and the following PRACH transmission may occur in consecutive subframes. A UE device may select from a special set of Zadoff-Chu sequences (different from a conventional set of sequences), to signal its status as a link-budget-limited device.