Patent application number | Description | Published |
20080273583 | CHANNEL ESTIMATION FOR OFDM-BASED WIRELESS COMMUNICATION SYSTEM USING SPARSELY SPACED PILOT SUBCARRIERS - A device and method for performing a channel estimation for an OFDM-based wireless communication system using sparsely spaced pilot subcarriers estimates missing pilot subcarriers in an interpolation window using pilot subcarriers that are outside of the interpolation window to produce estimated pilot subcarriers for the interpolation window. The pilot subcarriers in the interpolation window and the estimated pilot subcarrier are used to compute pilot channel estimates for the interpolation window, which are then used to derive data channel estimates for the interpolation window. | 11-06-2008 |
20080273615 | CHANNEL PROFILE ESTIMATION FOR OFDM-BASED COMMUNICATION SYSTEM - A device and method for performing a channel profile estimation for an OFDM-based wireless communication system uses an averaged frequency coherence metric to select a particular channel profile, which is a current channel profile estimate. The averaged frequency coherence metric is derived using correlations between pilot subcarriers of an OFDM-based signal at predefined subcarrier locations for multiple frames of the OFDM-based signal. The selected channel profile may be used for channel estimation, as well as for link adaptation, to improve the performance of these processes. | 11-06-2008 |
20080276147 | SYSTEM AND METHOD FOR PERFORMING A HARQ OPERATION IN AN OFDM-BASED RECEIVER - A system and method for performing a HARQ operation in an OFDM-based receiver utilizes a linked list scheme for a HARQ buffer, which is used to store soft information for HARQ entities with decoding errors. The device and method also combine soft information of a particular HARQ entity with previous updated soft information of the particular HARQ entity using a combined scaling factor that depends on a current scaling factor and a previous combined scaling factor. | 11-06-2008 |
20080291819 | SOFT-BIT DE-MAPPING DEVICE AND METHOD OF GENERATING SOFT BITS FOR DECODING - A soft-bit de-mapping device and method of generating soft bits for decoding quantizes a log-likelihood ratio (LLR) value for a received value using functions bits and channel parameter bits to generate the soft bits. The function bits are generated by quantizing an LLR function for the received value, which includes modifying an original curve of the LLR function to a modified curve such that a segment of the original curve with the lowest slope is protected in the modified curve for a fixed equal quantization step-size. The channel parameter bits are generated by quantizing a channel parameter for the received value to generate channel. | 11-27-2008 |
20100195747 | METHOD AND APPARATUS FOR PERFORMING JOINT DETECTION WITH A COMMON MIDAMBLE - Techniques for performing joint detection with a common midamble for downlink transmission are described. In one design, a user equipment (UE) may obtain samples for a burst transmitted by a Node B on the downlink. The burst may include at least one data field and a common midamble. The UE may derive a channel impulse response estimate for each of multiple orthogonal codes based on (i) a channel impulse response estimate derived based on samples for the common midamble and (ii) a traffic-to-pilot ratio (T2P) estimated for that orthogonal code based on the samples for burst. The UE may perform joint detection, for the multiple orthogonal codes, on samples for the at least one data field based on the multiple channel impulse response estimates. | 08-05-2010 |
20120115553 | ADAPTIVE ANTENNA DIVERSITY SYSTEM - Electronic devices may be provided that contain wireless communications circuitry. The wireless communications circuitry may include radio-frequency transceiver circuitry with first and second ports that are coupled by switching circuitry to first and second antennas. A first receiver in the transceiver circuitry may be associated with the first port and a second receiver in the transceiver circuitry may be associated with the second port. An electronic device may be operated in a single receiver mode in which only one of the receivers is active to conserve power or a dual receiver mode in which signals from both antennas may be received in parallel to compare antenna performance. Based on antenna performance metrics, the electronic device may adjust the switching circuitry to ensure that an optimal antenna is being used. | 05-10-2012 |
20120281553 | IDLE MODE RECEIVE ANTENNA DIVERSITY SYSTEM - Electronic devices may be provided that contain wireless communications circuitry. The wireless communications circuitry may include radio-frequency transceiver circuitry coupled to multiple antennas. An electronic device may alternate between a sleep mode and a wake mode. During wake mode, the electronic device may monitor a paging channel in a wireless network for incoming paging signals. The device may use either a single antenna mode or a multiple antenna mode such as a dual antenna mode in monitoring the paging channel. In the single antenna mode, a single active antenna is used to receive paging signals. In the dual antenna mode two antennas are simultaneously used to receive paging signals. The device may choose which antenna mode to use based on signal quality measurements and history information on successfully received paging signals. | 11-08-2012 |
20120282982 | ELECTRONIC DEVICE WITH IDLE MODE ANTENNA SWITCHING - Electronic devices may be provided that contain wireless communication circuitry. The wireless communication circuitry may include radio-frequency transceiver circuitry coupled to multiple antennas. An electronic device may alternate between a sleep mode and a wake mode. During wake mode, the electronic device may monitor a paging channel in a wireless network for incoming paging signals. The device may use a selected one of the multiple antennas in monitoring the paging channel. If received signal quality is satisfactory, the device may maintain use of the selected one of the multiple antennas for subsequent wake period monitoring of the paging channel. If received signal quality falls below a threshold or is otherwise indicated to not be satisfactory, the device may switch to use of a different one of the multiple antennas in monitoring the paging channel. Other criteria may also be used in controlling the switching between antennas for paging channel monitoring. | 11-08-2012 |
20130033996 | ELECTRONIC DEVICE WITH ANTENNA SWITCHING CAPABILITIES - Electronic devices may be provided that contain wireless communications circuitry capable of supporting time division multiple access. The wireless communications circuitry may include radio-frequency transceiver circuitry coupled to multiple antennas. Signal strength measurements may be gathered using the antennas and corresponding signal strength difference measurements may be computed to reflect which of the antennas is exhibiting superior performance. The signal strength measurements may be made by measuring receive power levels in a beacon channel during idle time slots while toggling its antennas in and out of use or by detecting for the presence of non-silent traffic channel frames or silence indicator description frames and measuring corresponding receive power levels while toggling its antennas in and out of use. Beacon-channel-based measurements and non-silent-frame-based measurements may be used for electronic devices with receive diversity by simultaneously receiving frames of interest using each of its antennas and making corresponding measurements in parallel. | 02-07-2013 |
20130035051 | ANTENNA SWITCHING SYSTEM WITH ADAPTIVE SWITCHING CRITERIA - Electronic devices may be provided that contain wireless communications circuitry. The wireless communications circuitry may include radio-frequency transceiver circuitry coupled to multiple antennas. Signal strength measurements may be gathered using the antennas and corresponding signal strength difference measurements may be produced to reflect which of the antennas is exhibiting superior performing. The signal strength difference measurements may be filtered using time-based averaging filters with different speeds. Corresponding filtered difference measurements may be compared to antenna switching criteria such as antenna switching thresholds. An antenna switching threshold may be adjusted in real time based on computations of how much variation is exhibited as a function of time between the difference measurements filtered using the filters of different speeds. Information on device movement or other data may be used in making threshold adjustments. | 02-07-2013 |
20130035084 | ADAPTIVE RANDOM ACCESS CHANNEL RETRANSMISSION - A mobile wireless device adapts transmit power levels and number of retransmissions of a preamble sent to a wireless network. The mobile wireless device measures characteristics of a downlink signal received from the wireless network. The mobile wireless device transmits a series of preambles to the wireless network, each successive preamble having an increased power level, starting at a power level based on the measured received signal characteristics and on parameters received from the wireless network, up to a maximum transmit power level. When the transmit power level of the preamble exceeds the maximum transmit power level and when the measured downlink signal quality falls below a threshold, the mobile wireless device limits the number of preamble retransmission to less than an allowed maximum number of retransmissions. A minimum number of retransmissions is determined and adapted to higher values for larger measured values of downlink signal quality. | 02-07-2013 |
20130035103 | METHODS FOR TRANSMIT ANTENNA SWITCHING DURING UPLINK ACCESS PROBING - Electronic devices may be provided that contain wireless communication circuitry. The wireless communication circuitry may include radio-frequency transceiver circuitry coupled to first and second antennas. An electronic device may send network access probe signals to a base station in a wireless network. If the base station responds with a corresponding acknowledgement, the electronic device and base station may establish a wireless communication link such as a cellular telephone link. In response to failure to receive the acknowledgement signal from the base station, the electronic device may increase the transmit power of a successive network access probe signal. The electronic device may switch between use of the first and second antennas when transmitting the network access probe signals. The electronic device may alternate between the first and second antennas or may use other antenna usage patterns. | 02-07-2013 |
20130064151 | ADAPTIVE RECEIVE DIVERSITY DURING DISCONTINUOUS RECEPTION IN MOBILE WIRELESS DEVICE - A mobile wireless device adapts receive diversity during discontinuous reception based on downlink signal quality, page indicators and page messages. When the downlink signal quality exceeds a pre-determined threshold, the mobile wireless device decodes a page indicator channel through an initial antenna, and otherwise, decodes a paging channel through the initial antenna without decoding the page indicator channel. The mobile wireless device switches to decoding the paging channel through an alternate antenna when a page indicator decodes as an erasure. When a paging message received through a single antenna decodes with an incorrect error checking code, the mobile wireless devices enables receive diversity through multiple antennas for subsequent decoding. The mobile wireless device switches between single antenna reception and multiple antenna reception based on tracking multiple consecutive error checking code failures and successes. | 03-14-2013 |
20130250785 | Adaptive Partial Packet Decoding - A user device receives packets from a base station. The user device may invoke decoding while the packet is still being received, based on the incomplete contents of a given packet. This “partial packet decoding” relies on the fact that the underlying information in the packet is encoded with redundancy (code rate less than one). If link quality is poor, the partial packet decoding is likely to be unsuccessful, i.e., to fail in its attempt to recover the underlying information. To avoid waste of power, the user device may be configured to apply one or more tests of link quality prior to invoking the partial packet decoding on a current packet. | 09-26-2013 |
20130267267 | Assisted Management of Radio Resources across Dual Networks - A user equipment (UE) operating in a communication system comprising a base station and one or more UEs. The UE may be configured to operate on or “camp” on two different networks with one radio. In this exemplary system, the radio may be normally connected to the first network (NW | 10-10-2013 |
20130272212 | METHOD FOR IMPLEMENTING AUTONOMOUS MANAGEMENT OF RADIO RESOURCES ACROSS DUAL NETWORKS - Managing radio resources across dual networks includes a wireless mobile device connecting to a first wireless network using a first radio access technology. The wireless device may notify the first network of a capability to be temporarily non-responsive to the first network while maintaining a signaling connection to the first network. The wireless device may communicate with a second network. The wireless device may return to communicating with the first network subsequent to communicating with the second network, and in response to communicating with the second network for less than a predetermined amount of time, the wireless device may send a scheduling request to the first network. In response to receiving a grant acknowledgement from the first network, the wireless device may send a buffer status report that includes a value such as zero to indicate that the wireless device has returned to and can communicate with the first network. | 10-17-2013 |
20130310057 | Fast Communication Recovery in Dual Network Radio Resource Management - Various embodiments are disclosed of a method and apparatus for fast communication recovery in wireless mobile devices arranged to perform dual network radio resource management. In one embodiment, a wireless mobile device includes a transceiver configured to communicate with each of first and second networks. After establishing and maintaining a link with the first network, the wireless mobile device may tune a transceiver to the second network to monitor for traffic, subsequently tuning back to the first network. After turning the transceiver back to the first network, the wireless mobile device may perform one or more attempts to restore the link to the first network. The number of attempts to restore the link is dependent upon an amount of time the transceiver is tuned to the second network. | 11-21-2013 |
20140003260 | Modulation and Coding Scheme (MCS) Recovery based on CQI Offset | 01-02-2014 |
20140071844 | POWER MANAGEMENT BASED ON ADAPTIVE RECEIVER SELECTION - In order to reduce power consumption of an electronic device during wireless communication, the electronic device may transition between a baseline (simple) receiver and a higher-power advanced receiver based on network conditions and/or environmental conditions. For example, the transition to the advanced receiver may occur when it offers improved communication performance over the baseline receiver, such as when there is significant interference and a high data rate, or when there is significant interference and a signal-to-noise ratio (SNR) is low. Similarly, the transition to the baseline receiver may occur when the capabilities of the advanced receiver are not needed, such as when there is less interference, or when the data rate is lower and the SNR is high. In this way, the electronic device can avoid the added power consumption associated with the advanced receiver except where the communication performance offered by the advanced receiver is needed. | 03-13-2014 |
20140126397 | DYNAMICALLY ADAPTING WIRELESS COMMUNICATION - In order to facilitate communication between an electronic device and another electronic device, the electronic device determines communication-quality metrics for a first connection in a wireless network based on received information from the other electronic device. Then, the electronic device calculates an overall communication-quality indicator for the first connection based on at least some of the communication-quality metrics. Moreover, the electronic device dynamically adapts the communication with the other electronic device based on the overall communication-quality indicator. For example, the electronic device may establish a second connection in a cellular-telephone network and may use the second connection to communicate with the other electronic device. Alternatively, the electronic device may provide the overall communication-quality indicator to the other electronic device and may at least partially transition the communication from the second connection in the cellular-telephone network to the first connection in the wireless network. | 05-08-2014 |
20140220916 | Adaptive Receive Diversity during Discontinuous Reception in Mobile Wireless Device - A mobile wireless device adapts receive diversity during discontinuous reception based on downlink signal quality, page indicators and page messages. When the downlink signal quality exceeds a pre-determined threshold, the mobile wireless device decodes a page indicator channel through an initial antenna, and otherwise, decodes a paging channel through the initial antenna without decoding the page indicator channel. The mobile wireless device switches to decoding the paging channel through an alternate antenna when a page indicator decodes as an erasure. When a paging message received through a single antenna decodes with an incorrect error checking code, the mobile wireless devices enables receive diversity through multiple antennas for subsequent decoding. The mobile wireless device switches between single antenna reception and multiple antenna reception based on tracking multiple consecutive error checking code failures and successes. | 08-07-2014 |