Patent application number | Description | Published |
20080279220 | PREAMBLE STRUCTURE AND ACQUISITION FOR A WIRELESS COMMUNICATION SYSTEM - Techniques for sending sector/system information in TDM pilots using a hierarchical pilot structure are described. A base station sends multiple sets of bits for the sector/system information in multiple TDM pilots. The set of bits sent in a given TDM pilot may include bits sent in earlier TDM pilots. In one design, the base station generates a first TDM pilot based on a first set of bits, generates a second TDM pilot based on a second set of bits that includes the first set, generates a third TDM pilot based on all bits for the information, and sends the TDM pilots. A terminal performs detection to obtain a first detected value for the first TDM pilot, performs detection based on the first detected value to obtain a second detected value for the second TDM pilot, and performs detection based on the first and second detected values to obtain a third detected value for the third TDM pilot. | 11-13-2008 |
20080304603 | METHODS AND APPARATUS FOR INITIAL ACQUISITION GAIN CONTROL IN A COMMUNICATION SYSTEM - Methods and apparatus for initial acquisition gain control in a communication system a method for use in a wireless communication system are disclosed. A disclosed methodology includes measuring the power of a signal received by a transceiver a number of times over a prescribed time period, the signal including a number of symbols. A gain of the transceiver is unidirectionally adjusted when a currently measured power is greater than a previously measured power during the prescribed time period until a maximal power level is measured. By adjusting the gain to accommodate a maximal power value, which is the same as the power level of an acquisition pilot symbol, overshoot and distortion by the transceiver are avoided during initial timing and frequency acquisition. Corresponding apparatus are also disclosed. | 12-11-2008 |
20080317142 | SYSTEM AND METHOD FOR FREQUENCY DIVERSITY - A system and method for frequency diversity uses interleaving in a wireless communication system utilizing orthogonal frequency division multiplexing (OFDM) with various FFT sizes. Subcarriers of one or more interlaces are interleaved in a bit reversal fashion and the one or more interlaces are interleaved in the bit reversal fashion. | 12-25-2008 |
20090059845 | METHOD AND APPARATUS FOR EFFICIENT SELECTION AND ACQUISITION OF SYSTEMS UTILIZING OFDM OR SC-FDM - Techniques for performing system selection and acquisition are described. In one design, a terminal may obtain at least one system record for at least one system utilizing orthogonal frequency division multiplexing (OFDM) or single-carrier frequency division multiplexing (SC-FDM). Each system record may include system identification information for an associated system and an index for an associated acquisition record. The terminal may also obtain at least one acquisition record for the at least one system. Each acquisition record may include at least one value for at least one configurable system parameter, e.g., FFT size, cyclic prefix length, number of guard subcarriers, etc. The terminal may perform acquisition for the at least one system in accordance with the at least one system record and the at least one acquisition record. The system and acquisition records may be stored in a Preferred Roaming List (PRL) or a Most Recently Used (MRU) list. | 03-05-2009 |
20090067352 | METHODS AND APPARATUS FOR INCLUDING MODE INFORMATIONIN A FRAME FOR SYSTEM ACQUISITION - Methods and apparatus for including mode information in a wireless transmission frame, which is useful for system acquisition. In particular, a first information bit is provided in a preamble of a transmission frame, where the bit is configured to indicate that a wireless communication system is operating according to either a time division duplex (TDD) mode or a frequency division duplex (FDD) mode. The addition of a single bit minimally affects the resources of the preamble. Additionally, another bit resource already present in the preamble for normally communicating whether FDD transmissions are full duplex or half-duplex transmissions, may be further allocated to indicate partitioning information concerning TDD mode transmissions when the first bit indicates TDD mode, thus affording additional information communicated in the frame without increasing preamble resources. | 03-12-2009 |
20090116574 | METHODS AND APPARATUS FOR RECEIVE POWER UNIFICATION FOR MIMO AND NON-MIMO SIGNALING - A method for receive power unification for multiple-input and multiple-output (MIMO) and non-MIMO signaling is described. A data stream may be separated into multiple individual data streams for transmission by multiple transmit antennas. Orthogonal frequency division multiplexing (OFDM) may be applied to the individual data streams to obtain one or more OFDM symbols. Unification processing may be applied to an OFDM symbol. Individual data streams may be transmitted using multiple transmit antennas. | 05-07-2009 |
20090161776 | SYSTEM AND METHOD FOR FREQUENCY DIVERSITY - A system and method for frequency diversity uses interleaving in a wireless communication system utilizing orthogonal frequency division multiplexing (OFDM) with various FFT sizes. Subcarriers of one or more interlaces are interleaved in a bit reversal fashion and the one or more interlaces are interleaved. | 06-25-2009 |
20090232079 | FRAME STRUCTURES FOR WIRELESS COMMUNICATION SYSTEMS - Superframe preamble structures for wireless communication systems are provided. The preamble can include system determination information, which can improve acquisition performance. The superframe structures can allow efficient determination of flexible parameters that determine preamble structure. The superframe structures can also facilitate quick paging capacity to scale with bandwidth. | 09-17-2009 |
20090310552 | APPARATUS AND METHOD FOR CELL-BASED HIGHLY DETECTABLE PILOT MULTIPLEXING - An apparatus and method for cell-based highly detectable pilot (HDP) multiplexing comprising determining if an HDP opportunity exists; selecting a subslot within the HDP opportunity for transmission of a HDP signal; and activating more than one sector within a cell for the transmission of the HDP signal. | 12-17-2009 |
20100014603 | GUARD INDEPENDENT SIGNAL MAPPING - Systems and methodologies are described that facilitate guard bandwidth independent mapping and de-mapping of bandwidth in a wireless communication system. Broadcast signals can be created as if all bandwidth were available, and guard bandwidth can be initialized over the utilized bandwidth such to puncture the data existing in the guard bandwidth. Upon decoding the broadcast signal, size of the guard bandwidth can be predetermined or estimated allowing a center portion of the signal to be decoded without decoding the guard bandwidth. In this regard, the decoder of the signal need not find exact positions of the guard bandwidth as transforming and decoding the center portion can provide a substantial portion of the signal to interpret the signal. | 01-21-2010 |
20100027486 | ACQUISITION PILOTS FOR WIRELESS COMMUNICATION SYSTEMS - System(s) and method(s) are provided to facilitate generating and processing acquisition pilots in wireless communications. Acquisition pilots that convey timing and frequency synchronization information, wireless system acquisition and system determination information are modulated with pseudorandom sequences. The R bits of information carried by the acquisition pilot that conveys system determination information are augmented with T bits that convey a counter index associated with the system timing of superframes transmitted from an access point. The processing overhead resulting from the addition of the T bits is offset by the advantages afforded to a wireless communication. Salient advantages include: (i) processing gain at a receiver for communication in a specific sector during asynchronous operation, (ii) packet boundary determination through the counter field values, and (iii) initialization of various pseudorandom registers employed for communication. | 02-04-2010 |
20100034242 | METHODS AND APPARATUS FOR DETERMINING TIMING IN A WIRELESS COMMUNICATION SYSTEM - Methods and apparatus for setting timing of sampling of one or more symbols. The disclosed methods account for at least three types of effective interference (EI) and are used to set the timing of a sampling window for sampling received symbols. The methods includes setting timing based on determining an energy density function accounting for both static and dynamic EI, determining the minimum of a total energy profile and sliding the sampling window to ensure that the minimum point is at a predetermined point, and determining and using a composite energy profile accounting for short term and long term fading effects. The disclosed apparatus include a transceiver employing one or more of the disclosed methods for setting timing when receiving the symbols. | 02-11-2010 |
20100284280 | CHANNEL ESTIMATE PRUNING IN PRESENCE OF LARGE SIGNAL DYNAMICS IN AN INTERFERENCE CANCELLATION REPEATER - A method for estimating a feedback channel for a wireless repeater detects changes in a power of a remote signal. When a large power swing in the remote signal is detected, the method operates to discard samples or blocks of samples of the pilot and receive signals and a final channel estimate is generated using undiscarded samples of the pilot and receive signals. Alternately, sub channel estimates are generated using individual blocks of the pilot samples and receive samples. When a large power swing in the remote signal is detected, the method operates to discard one or more sub channel estimates and a final channel estimate is generated using undiscarded sub channel estimates. | 11-11-2010 |
20100284445 | INSERTED PILOT CONSTRUCTION FOR AN ECHO CANCELLATION REPEATER - In one embodiment, a device for constructing a pilot signal for use in a wireless repeater where the pilot signal is added to a transmit signal includes one or more pilot generators. Each pilot generator generates a carrier pilot signal associated with a single carrier of the transmit signal and the carrier pilot signals generated by the one or more pilot generators are summed to generate the pilot signal. Each of the one or more pilot generators includes a pilot symbol unit providing multiple data symbols having a predetermined data structure as the carrier pilot signal, a pilot scrambler, a filter, a pilot power determination unit, and a cyclic prefix insertion unit for inserting a cyclic prefix, to the carrier pilot signal. In another embodiment, the pilot symbol unit providing multiple data symbols in frequency domain as the carrier pilot signal. | 11-11-2010 |
20100284447 | FREQUENCY DOMAIN FEEDBACK CHANNEL ESTIMATION FOR AN INTERFERENCE CANCELLATION REPEATER INCLUDING SAMPLING OF NON CAUSAL TAPS - A method for estimating a feedback channel for a wireless repeater uses frequency domain channel estimation on samples of a pilot signal and samples of a receive signal. The pilot signal samples may be delayed to align the largest channel tap to a given reference time. A time domain feedback channel is generated by retaining both the causal taps and the non-causal taps of the channel estimate. | 11-11-2010 |
20100285733 | WIDEBAND ECHO CANCELLATION IN A REPEATER - A wireless repeater having a receiving antenna for receiving an input signal and a transmitting antenna for transmitting an amplified signal includes first and second front-end circuits and a repeater baseband block coupled between the first and second front-end circuits. The repeater baseband block includes a channel estimation block, an echo canceller implementing time domain echo cancellation, a variable gain stage controlled by a gain control block implementing digital gain control, a first variable delay element introducing a first delay before or after the echo canceller, a second variable delay element introducing a second delay to the output signal. The delayed output signal is coupled to the channel estimation block as a reference signal for estimating the feedback channel, to the echo canceller as a reference signal for estimating the feedback signal, and to the gain control block for monitoring the stability of the repeater. | 11-11-2010 |
20100285738 | SIGNAL BLANKING FOR IMPROVED FREQUENCY DOMAIN CHANNEL ESTIMATION - A wireless repeater includes a channel estimation block to estimate a feedback channel between the antennas of the repeater using frequency domain channel estimation. The repeater includes a pilot signal blanking circuit to blank out a selected number of samples of the pilot signal to improve the accuracy of the channel estimation. In another embodiment, the repeater replaces T samples of the pilot signal with a cyclic prefix. | 11-11-2010 |
20100285739 | MULTI-METRIC GAIN CONTROL FOR WIRELESS REPEATER - A method for controlling gain in a wireless repeater includes using two or more gain control metrics indicative of stability of the repeater, at least two of the gain control metrics having different integration lengths, where the integration length is the sum of the coherent integration time and the non coherent integration time, and controlling a variable gain value of the repeater based on one or more of the selected gain control metric(s) where the gain control metric(s) to use is selected based on the stability of the repeater. | 11-11-2010 |
20100285740 | STABILITY INDICATOR FOR A WIRELESS REPEATER - A method for monitoring feedback loop stability in a wireless repeater includes measuring a gain control metric in the feedback loop of the repeater periodically for a given time period where the gain control metric is indicative of a loop gain of the feedback loop of the repeater; and monitoring the magnitude of the gain control metric to determine the stability of the feedback loop of the repeater. In operation, a large magnitude of the gain control metric indicates instability in the feedback loop of the repeater. | 11-11-2010 |
20100285741 | GAIN ADJUSTMENT STEPPING CONTROL IN A WIRELESS REPEATER - A method for controlling gain in a wireless repeater includes providing one or more gain control metrics where the gain control metrics is indicative of a loop gain of the repeater; measuring the one or more gain control metrics; and adjusting a variable gain of the repeater using a gain adjustment step size being a function of at least the loop gain of the repeater as measured by the one or more gain control metrics. In another embodiment, the gain control algorithm block is configured to divide the loop gain of the repeater into multiple gain adjustment control zones. The gain adjustment control zones may include a first zone having a loop gain in a stable operating region and a second zone having a loop gain outside the stable operating region. | 11-11-2010 |
20100285742 | GAIN CONTROL METRIC PRUNING IN A WIRELESS REPEATER - A method for controlling gain in a wireless repeater includes computing a gain control metric indicative of a loop gain of the repeater and detecting changes in a signal power of a gain control input signal where the gain control input signal is taken from any point in the feedback loop of the repeater. When a large power swing in the gain control input signal is detected, the method operates to discard at least a portion of each gain control metric measurement for a first duration before continuing with computing the gain control metric. In another embodiment, the method may include discarding samples of the gain control input signal used in computing the gain control metric for a first duration when a large power swing in the gain control input signal is detected. | 11-11-2010 |
20100285744 | GAIN CONTROL METRIC COMPUTATION IN A WIRELESS REPEATER - A method for computing a gain control metric used in controlling gain in a wireless repeater operates to store correlation and normalization values associated with the gain control metric for the previous N samples in registers. For each new sample of the gain control input signal, the correlation and normalization values are computed by discarding the multiplication terms of the obsolete sample and adding the multiplication terms of the new sample to the stored correlation and normalization values. In this manner, the complexity of the computation is greatly reduced and the complexity of the computation does not increase with the integration length. | 11-11-2010 |
20100316044 | TIMING SYNCHRONIZATION AND CHANNEL ESTIMATION AT A TRANSITION BETWEEN LOCAL AND WIDE AREA WAVEFORMS USING A DESIGNATED TDM PILOT - Systems and methods are provided for channel estimation and timing synchronization in a wireless network. In an embodiment, a method is provided for time synchronization at a wireless receiver. The method includes decoding at least one TDM pilot symbol located at a transition between wide and local waveforms and processing the TDM pilot symbol to perform time synchronization for a wireless receiver. Methods for channel estimation at a wireless receiver are also provided. This includes decoding at least one TDM pilot symbol and receiving the TDM pilot symbol from an OFDM broadcast to facilitate channel estimation for a wireless receiver. | 12-16-2010 |
20110058469 | WIDE AREA AND LOCAL NETWORK ID TRANSMISSION FOR COMMUNICATION SYSTEMS - The embodiments utilize OFDM symbols to communicate network IDs. The IDs are encoded into symbols utilizing the network IDs as seeds to scramble respective pilots that are then transmitted by utilizing the symbols. The pilots can be structured into a single OFDM symbol and/or multiple OFDM symbols. The single symbol structure for transmitting the network IDs is independent of the number of network ID bits and minimizes frequency offset and Doppler effects. The multiple symbol structure allows a much coarser timing accuracy to be employed at the expense of transmitting additional symbols. Several embodiments employ a search function to find possible network ID candidates from a transmitted symbol and a selection function to find an optimum candidate from a network ID candidate list. | 03-10-2011 |
20110064007 | METHODS AND APPARATUS FOR INCLUDING MODE INFORMATION IN A FRAME FOR SYSTEM ACQUISITION - Methods and apparatus for including mode information in a wireless transmission frame, which is useful for system acquisition. In particular, a first information bit is provided in a preamble of a transmission frame, where the bit is configured to indicate that a wireless communication system is operating according to either a time division duplex (TDD) mode or a frequency division duplex (FDD) mode. The addition of a single bit minimally affects the resources of the preamble. Additionally, another bit resource already present in the preamble for normally communicating whether FDD transmissions are full duplex or half-duplex transmissions, may be further allocated to indicate partitioning information concerning TDD mode transmissions when the first bit indicates TDD mode, thus affording additional information communicated in the frame without increasing preamble resources. | 03-17-2011 |
20110080924 | METHOD FOR TRANSMISSION OF TIME DIVISION MULTIPLEXED PILOT SYMBOLS TO AID CHANNEL ESTIMATION, TIME SYNCHRONIZATION, AND AGC BOOTSTRAPPING IN A MULTICAST WIRELESS SYSTEM - Systems and methods are provided for the transmission of waveforms to aid channel estimation, timing synchronization, and AGC bootstrapping in a wireless network. The method includes inserting at least one TDM pilot symbol located at a transition between wide area and local area waveforms to facilitate decoding of the transmission block. | 04-07-2011 |
20110116533 | APPARATUS AND METHODS FOR REDUCING CHANNEL ESTIMATION NOISE IN A WIRELESS TRANSCEIVER - Apparatus and methods for use in a wireless communication system are disclosed for reducing channel estimation noise in a device such as a wireless transceiver. A disclosed apparatus includes a processor that determines a channel activity portion and a noise portion of a channel estimation. The processor also determines a threshold noise level based on channel estimate values in the noise portion of the channel estimation. The processor compares channel estimate energy values in the channel estimation to the threshold noise level and sets each of the channel estimate energy values being less than the threshold noise level to a predetermined value such as zero in order to reduce or eliminate the noise. Similar methods are also disclosed. | 05-19-2011 |
20110223853 | GAIN CONTROL METRIC COMPUTATION IN A WIRELESS REPEATER - A wireless repeater includes a gain control metric computation block to compute a gain control metric for use in controlling the variable gain of the repeater. The gain control metric is computed by downsampling the gain control input signal to the gain control metric computation block and also downsampling the computed correlation and normalization terms. The gain control metric may be further enhanced by filtering the computed metric values using linear or non-linear filtering. | 09-15-2011 |
20120263167 | TIMING AND FREQUENCY ACQUISITION FOR WIRELESS NETWORKS - Systems and methods are provided for processing Time Domain Multiplexing Pilot symbols by employing complex accumulators to determine peak values which indicate the start of timing and frequency information. In an embodiment, a method is provided for timing acquisition in a wireless network. The method includes acquiring samples from an Orthogonal Frequency Division Multiplexing (OFDM) data packet over a predetermined period of time, where the samples include one or more TDM pilot symbols. The samples are then processed to determine a maximum value that indicates the TDM pilot symbol has been detected. | 10-18-2012 |
20120264369 | BEACON SIGNALS FOR REPEATERS WITHIN A WIRELESS COMMUNICATIONS SYSTEM - In an embodiment, a first repeater configures a beacon signal that identifies the first repeater to one or more other repeaters. The first repeater transmits the configured beacon signal at a given transmission power level to the one or more other repeaters. The transmitted beacon signal is received at least by a second repeater. The second repeater reduces interference associated with other transmissions from the first repeater, such as retransmissions of donor signals, based on the received beacon signal. | 10-18-2012 |
20120314646 | ECHO CANCELLATION REPEATER USING AN INSERTED PILOT WITH GAIN-BASED POWER LEVEL CONTROL SCHEME - A device for generating a pilot signal for use in a wireless repeater where the pilot signal is added to a transmit signal for transmission includes a pilot power control unit configured to set a power level of the pilot signal as a function of a gain of the repeater and a power level of the transmit signal, where the function comprises a linear or non-linear function. In one embodiment, the operation of the repeater may be divided into gain regions and the inserted pilot power is controlled according to the different gain regions of the repeater. When the repeater gain is low, the pilot power may be set greater than the transmit power to ensure there is sufficient signal to use for channel estimation. When the repeater gain is in steady state, the pilot power may be set to be lower than the transmit power to avoid interference. | 12-13-2012 |
20130034128 | ECHO CANCELLATION REPEATER OPERATION IN THE ABSENCE OF AN INPUT SIGNAL - A wireless repeater introduces a low level noise to the signal path of the repeater where the introduced noise is used to facilitate channel estimation. The introduced low power level noise may be added to the receive signal or to the transmit signal. The low power noise signal ensures that the repeater always has a reference signal for performing channel estimation, even when the repeater is not receiving any incoming signal traffic. In one embodiment, a low noise signal is inserted to the transmit circuit of the repeater. In another embodiment, the repeater is configured to increase the noise figure of the receive circuit where the detected noise figure acts as a receive signal. | 02-07-2013 |
20130078907 | PER CARRIER GAIN CONTROL IN A MULTI-CARRIER REPEATER - A method for adjusting per-carrier gains in a repeater is presented. The method may include determining a separate gain value for each carrier frequency in a signal. The method may further include applying the separate gain value to each carrier frequency in the signal to form a per-carrier gain adjusted signal. The method may also include adjusting the separate gain values based upon a per-carrier stability metric. | 03-28-2013 |
20130122802 | ESTIMATION OF REPEATER LOOP DELAY FOR REPEATER GAIN CONTROL - Methods and apparatus for estimating a loop delay value (N | 05-16-2013 |
20130142222 | WIRELESS REPEATER IMPLEMENTING MULTI-PARAMETER GAIN MANAGEMENT - A wireless repeater incorporates a gain management block to implement a multi-parameter gain management algorithm. The gain management algorithm receives gain settings from at least a gain control metric for stability and output signal quality and signal headroom values associated with circuitry of the repeater. The gain management block provides secure and robust boot-up of the repeater as well as oscillation detection and prevention. Furthermore, the gain management block implements repeater stability control, output signal-to-noise level control, uplink and downlink gain balance control and compensation for device constraints. | 06-06-2013 |
20130143483 | MAINTAINING REPEATER STABILITY IN A MULTI-REPEATER SCENARIO - A wireless repeater in a multi-repeater environment operates to detect the presence of neighboring repeaters and to maintain repeater stability in the presence of a neighboring repeater. In some embodiments, the repeater transmits a known signal sequence to discover the presence of a neighboring repeater. When a neighboring repeater is detected, the repeater may apply mitigation measures to maintain operational stability at the repeater. | 06-06-2013 |
20130156124 | SYSTEM AND METHOD FOR FREQUENCY DIVERSITY - A system and method for frequency diversity uses interleaving in a wireless communication system utilizing orthogonal frequency division multiplexing (OFDM) with various FFT sizes. Subcarriers of one or more interlaces are interleaved in a bit reversal fashion and the one or more interlaces are interleaved in the bit reversal fashion. | 06-20-2013 |
20130235783 | EVOLVED MULTIMEDIA BROADCAST MULTICAST SERVICE CAPACITY ENHANCEMENTS - A method, an apparatus, and a computer program product for wireless communication are provided in which a first cell receives a configuration identifying a plurality of transmission layers in a multi-layer spatial multiplexing scheme of a Multi-Media Broadcast over a Single Frequency Network (MBSFN). The configuration may identify resource block allocations to transmission layers, seed values for pattern generation, and timing information used to allocate resource blocks to transmission layers. The first cell transmits a first set of resource blocks during a first period of time using a first transmission layer to one or more user equipments (UE) located in the MBSFN. Another cell located in the MBSFN may concurrently transmit a second set of resource blocks to the UE in a second transmission. | 09-12-2013 |
20130329617 | APPARATUS AND METHODS FOR CONTROL OF SLEEP MODES IN A TRANSCEIVER - Disclosed are apparatus and methods for control of sleep modes in a transceiver or receiver. In particular, a transceiver is disclosed including a processor configured to determine timing information concerning sleep periods for at least a portion of components within the transceiver. The transceiver also includes a sleep control logic coupled to the processor to receive information concerning sleep periods from the processor and configured to effect shutting down of the at least a portion of the components of the transceiver during power reduction periods independent of the processor. | 12-12-2013 |
20140092893 | PREAMBLE STRUCTURE AND ACQUISITION FOR A WIRELESS COMMUNICATION SYSTEM - Techniques for sending sector/system information in TDM pilots using a hierarchical pilot structure are described. A base station sends multiple sets of bits for the sector/system information in multiple TDM pilots. The set of bits sent in a given TDM pilot may include bits sent in earlier TDM pilots. In one design, the base station generates a first TDM pilot based on a first set of bits, generates a second TDM pilot based on a second set of bits that includes the first set, generates a third TDM pilot based on all bits for the information, and sends the TDM pilots. A terminal performs detection to obtain a first detected value for the first TDM pilot, performs detection based on the first detected value to obtain a second detected value for the second TDM pilot, and performs detection based on the first and second detected values to obtain a third detected value for the third TDM pilot. | 04-03-2014 |
20140258801 | MANAGING NULL PACKETS - Systems and methods are provided for mitigating interference in a wireless network to facilitate network performance. In an aspect, a method for transmitting wireless data packets is provided. The method includes receiving data packets from a wireless distribution network. The data packets are analyzed to determine if a subset of the data packets are to be suppressed in view of transmitter signal conditions and substituting null packets for the subset of data packets if the subset of data packets are determined to be suppressed. | 09-11-2014 |
20140341050 | CHANNEL ESTIMATE UNDER NON-UNIFORM REFERENCE SIGNAL PATTERN - Reference signals may not uniformly span over time and/or frequency on a resource unit. For example, reference signals may non-uniformly occupy symbols of a subframe. Alternatively, reference signals normally transmitted over certain tones of a subframe may have to be punctured to avoid collisions with a PSS and/or SSS transmitted over the same tones. Consequently, a UE may only be able to use a subset of reference signal tones for performing channel estimation. Accordingly, a method, an apparatus, and a computer program product for wireless communication are provided for improving channel estimation under a non-uniform signal pattern. The apparatus indicates to a UE to utilize a subset of reference signals to derive a channel estimate for demodulating data in a specific subframe, and transmits a plurality of subframes, the plurality of subframes including the reference signals and the specific subframe, the specific subframe including a PSS and/or SSS. | 11-20-2014 |