Abstract: Techniques are disclosed relating to DC interference cancelation in received wireless signals. Disclosed techniques may be performed in the digital domain, in conjunction with analog cancelation techniques. In some embodiments, a receiver apparatus operates a local oscillator at a frequency corresponding to a particular pilot symbol in a received wireless signal. In some embodiments the receiver estimates DC interference at the frequency based on the received pilot symbol (this may be facilitated by the fact that the contents of pilot symbols are known, because they are typically used for channel estimation). In some embodiments, the receiver apparatus is configured to cancel the DC interference based on the estimate to determine received data in subsequently received signals at the frequency. Disclosed techniques may allow narrowband receivers to efficiently use more of their allocated frequency bandwidth, rather than wasting bandwidth near the frequency of the local oscillator.

Abstract: This disclosure relates to techniques for providing robust downlink control information with flexible resource assignments for wireless devices that operate in a restricted bandwidth compared to the system bandwidth. A base station may determine a resource assignment for a wireless device. The base station may transmit downlink control information to the wireless device. The downlink control information may include an indication of a resource assignment for the wireless device. The indication of the resource assignment may include an indication of a first narrowband associated with the resource assignment, and an indication of whether one or more additional narrowbands are associated with the resource assignment. The base station and the wireless device may communicate data according to the resource assignment.

Abstract: This disclosure relates to techniques for selecting operational modes of a wireless device. The operational mode may be selected based on determining the presence or absence of reference symbols. A low power mode may be selected when the presence or absence of reference symbols suggests that a control channel used by the wireless device may not be present.

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: A wireless communication device may operate in different power modes based at least on a decoding of a Physical Data Control Channel (PDCCH). The wireless communication device may operate its receiver front end circuitry (RX AFE) in any one of a number of different power modes, and may switch to operating the RX AFE in a different power mode based at least on decoding of the PDCCH. The transmit leakage does not need to be monitored, and the wireless communication device may adjust/adapt the sensitivity and linearity of its RX AFE based on PDCCH decoding and in some cases based additionally on one or more metrics, to reduce power consumption. The different power modes may correspond to different respective combinations of sensitivity level and linearity level at which the RX AFE is operating.

Abstract: This disclosure relates to techniques for providing robust downlink control information with flexible resource assignments for wireless devices that operate in a restricted bandwidth compared to the system bandwidth. A base station may determine a resource assignment for a wireless device. The base station may transmit downlink control information to the wireless device. The downlink control information may include an indication of a resource assignment for the wireless device. The indication of the resource assignment may include an indication of a first narrowband associated with the resource assignment, and an indication of whether one or more additional narrowbands are associated with the resource assignment. The base station and the wireless device may communicate data according to the resource assignment.

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 techniques for supporting narrowband device-to-device (D2D) wireless communication, including possible techniques for providing synchronization and master information block signals in an off grid radio system. A wireless device may provide D2D synchronization signals for a D2D communication group. The D2D synchronization signals may be provided using multiple frequency channels. The D2D synchronization signals may be provided on each respective frequency channel of the frequency channels during a respective portion of a D2D synchronization signal cycle in a sequential manner.

Abstract: Apparatuses, systems, and methods to perform attachment of a wireless device to substantially concurrent connections with a next generation network node and a legacy network node. The wireless device may be configured to transmit a request to attach to a first network node operating according to the first RAT and transmit an indication that the wireless device is capable of maintaining substantially concurrent connections with the first network node and a second network node that operates according to the second RAT. The wireless device may also be configured transmit a request to attach to the second network node. The request may include an indication that the wireless device is capable of maintaining substantially concurrent connections with the first and second network nodes. Further, the wireless device may be configured to receive an indication that dual connectivity with the first and second network nodes has been established.

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: 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 providing robust downlink control information with flexible resource assignments for wireless devices that operate in a restricted bandwidth compared to the system bandwidth. A base station may determine a resource assignment for a wireless device. The base station may transmit downlink control information to the wireless device. The downlink control information may include an indication of a resource assignment for the wireless device. The indication of the resource assignment may include an indication of a first narrowband associated with the resource assignment, and an indication of whether one or more additional narrowbands are associated with the resource assignment. The base station and the wireless device may communicate data according to the resource assignment.

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: 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: 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: 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: 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: 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.