BR122020021801B1 - CHANNEL ESTIMATE IMPROVEMENTS - Google Patents

Abstract

The description relates in some respects to techniques for enhanced channel estimation. For example, a device can specify a pilot structure where the pilot density differs with time. As another example, a device may indicate that a pilot from a previous transmission time slot (TTI) may be used for channel estimation. As another example, a device may employ frequency domain physical resource block (PRB) bundling with bundling information signaling. As another example, a device might use an adjustable traffic-to-pilot ratio (TPR) for throughput optimization. Other aspects, modalities and characteristics are also discussed and claimed.

Description

CROSS-REFERENCE TO RELATED ORDERS

[0001] This application claims priority over and benefits from Provisional Application No. 62/073,683, filed with the US Patent and Trademark Office on October 31, 2014, and Non-Provisional Application No. 14/705,787, filed with the US Patent and Trademark Office. US Patents and Trademarks on May 6, 2015, the entire contents of which are incorporated herein by reference.

INTRODUCTION

[0002] Aspects of the description generally refer to wireless communication, and more specifically, but not exclusively, to techniques for improving channel estimation that may be useful for providing better estimates of channel quality and/or reduced latency associated with decoding based on channel estimates.

[0003] Wireless communication networks are widely developed to provide various communication services such as telephony, video, data, messaging, broadcasting and so on. Such networks, which are typically multiple access networks, support communications for multiple users by sharing available network resources.

[0004] In many wireless communication networks, a wireless device decodes and/or demodulates received data based on an estimate of the channel through which the data has traveled. Some wireless communication networks employ pilot-assisted channel estimation where a base station (e.g. an enhanced Node B (eNB)) broadcasts the pilot signals and an access terminal (e.g. a mobile device such as (UE)) that receives the pilot signals generates a channel estimate based on the pilot signals. For example, in the Long Term Evolution (LTE) of the 3rd Partnership Project. Generation (3GPP, an eNB broadcasts a pilot reference signal such as a demodulation reference signal (DMRS), where a UE receiving the pilot reference signal generates a channel estimate based on the received pilot reference signal.

[0005] Conventionally (eg in LTE), DMRS pilots are fixed both in time and frequency. Also, in LTE, DMRS pilots are transmitted at the end of each partition. In this way, a set of pilots can be estimated only at the end of a given transmission time interval (TTI).

BRIEF SUMMARY OF SOME EXAMPLES

[0006] The following is a simplified summary of some aspects of the description to provide a basic understanding of such aspects. This summary is not intended to be an extensive overview of all features contemplated in the description and is not intended to identify key or critical elements of all aspects of the description or to delineate the scope of any or all aspects of the description. Its sole purpose is to present various concepts of some aspects of the description in a simplified form as an introduction to the more detailed description that will be presented later.

[0007] In one aspect, the description provides an apparatus configured for communication. The apparatus includes a processing circuit configured to determine a pilot structure where the pilot density differs with time within a transmission period; and a communication interface coupled to the processing circuit and configured to transmit an indication of the pilot frame.

[0008] Another aspect of the description provides a method of communication including determining a pilot structure where the pilot density differs with time within a transmission period; and transmitting a pilot frame indication.

[0009] Another aspect of the description provides an apparatus configured for communication. The apparatus including means for determining a pilot structure where the pilot density differs with time within a transmission period; and means for transmitting an indication of the pilot frame.

[0010] Another aspect of the disclosure provides a non-transient computer-readable medium for storing computer-executable code, including a code for determining a pilot structure where the pilot density differs with time within a transmission period; and transmitting an indication of the pilot structure.

[0011] These and other aspects of the description will become more fully understood after a review of the detailed description, which follows. Other aspects, features, and implementations of the description will become apparent to those skilled in the art upon review of the following description of specific implementations of the description in conjunction with the accompanying figures. While features of the description may be discussed with respect to certain implementations and figures below, all implementations of the description may include one or more advantageous features discussed herein. In other words, while one or more implementations may be discussed as having certain advantageous characteristics, one or more of these characteristics may also be used in accordance with various implementations of the description discussed here. Similarly, while certain implementations may be discussed below as device, system, or method implementations, it should be understood that such implementations may be implemented in a variety of devices, systems, and methods.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a block diagram illustrating an example of an access network in which one or more aspects of the description may have application.

[0013] Figure 2 is a block diagram illustrating an example of an access terminal in communication with an access point in a communication system in accordance with some aspects of the description.

[0014] Fig. 3 is a block diagram illustrating an example of a communication system where a base station (BS) signals a pilot structure to a UE in accordance with some aspects of the description.

[0015] Figure 4 illustrates an example of a pilot structure in accordance with some aspects of the description.

[0016] Fig. 5 is a block diagram illustrating another example of a communication system where a base station (BS) signals a TTI filtering indication to a UE in accordance with some aspects of the description.

[0017] Fig. 6 is a block diagram illustrating another example of a communication system where a base station (BS) signals a Physical Resource Block (PRB) beaming indication to a UE in accordance with some aspects of the description.

[0018] Fig. 7 is a block diagram illustrating another example of a communication system where a base station (BS) signals a traffic ratio to pilot (TPR) indication to a UE in accordance with some aspects of the description.

[0019] Figure 8 is a block diagram illustrating an illustrative hardware implementation for an apparatus (eg, an electronic device) that can perform one or more of the methods to support communication in accordance with some aspects of the description.

[0020] Figure 9 is a flowchart illustrating an example of a process for communication according to some aspects of the description.

[0021] Figure 10 is a flowchart illustrating an example of a process involving the determination of a pilot structure in accordance with some aspects of the description.

[0022] Figure 11 is a block diagram illustrating an illustrative hardware implementation for another apparatus (eg, an electronic device) that can perform one or more of the methods to support communication in accordance with some aspects of the description.

[0023] Figure 12 is a flowchart illustrating an example of a process for communication according to some aspects of the description.

[0024] Figure 13 is a block diagram illustrating an illustrative hardware implementation for another apparatus (eg, an electronic device) that can perform one or more of the methods to support communication in accordance with some aspects of the description.

[0025] Figure 14 is a flowchart illustrating an example of a process involving the transmission of a pilot indication in accordance with some aspects of the description.

[0026] Figure 15 is a flow chart illustrating an example of a process involving the transmission of an indication of a pilot frame in accordance with some aspects of the description.

[0027] Figure 16 is a flow chart illustrating an example of a process involving the transmission of a traffic ratio to pilot (TPR) indication in accordance with some aspects of the description.

[0028] Figure 17 is a block diagram illustrating an illustrative hardware implementation for another apparatus (eg, an electronic device) that can perform one or more methods to support communication in accordance with some aspects of the description.

[0029] Figure 18 is a flowchart illustrating an example of a process involving the generation of a channel estimate in accordance with some aspects of the description.

[0030] Figure 19 is a flowchart illustrating another example of a process involving the generation of a channel estimate in accordance with some aspects of the description.

[0031] Figure 20 is a flowchart illustrating an example of a process involving the selection of a transmission energy according to some aspects of the description.

[0032] Figure 21 illustrates an example of a wireless communication network within which aspects of the description can be implemented.

DETAILED DESCRIPTION

[0032] The detailed description presented below with respect to the accompanying drawings is intended to serve as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing an in-depth understanding of the various concepts. However, it will be apparent to those skilled in the art that these concepts can be practiced without these specific details. In some cases, well-known structures and components are illustrated in block diagram form in order to avoid obscuring such concepts.

[0033] The description refers in some respects to improvements in channel estimation. For example, a first device can adapt its pilots and/or provide information to improve channel estimation in a second device. As a more specific example, an access point (e.g., a base station such as an eNB) can adapt its pilots and/or provide information to improve channel estimation at an access terminal. Through the use of the described techniques, better estimates of channel quality can be achieved and/or the latency associated with decoding based on channel estimates can be reduced.

[0034] The description relates in some respects to a pilot structure having a varying pilot density. For example, the pilot density may be greater (e.g., greater by at least one of time, frequency, or energy) at the beginning of a data burst than it is at a later part of the data burst. As a non-limiting example, a first TTI of a data burst may include four pilots while subsequent TTIs of the data burst include two pilots. Accordingly, a device can obtain information for channel estimation in advance compared to conventional techniques. In addition, a device can use periodic pilot updates to improve channel estimation.

[0035] The description refers in some aspects to filtering techniques through TTI. For example, a device can apply pilot filtering through subframes (SFs). As a more specific example, a device can use information that was previously obtained for a previous TTI or frame to filter a current TTI or frame.

[0036] In some respects, these two techniques facilitate immediate demodulation in a device (eg, an access terminal). Consequently, in some cases, improvements can be seen in demodulation latency, decode latency, and memory requirements.

[0037] The description relates in some respects to improved frequency domain physical resource block (PRB) bundling. For example, a device can specify a uniform pilot structure with PRB bundling to facilitate channel estimation. Additionally, network signaling (NW) of a precoding matrix indicator (PMI) can allow joint channel estimation across multiple PRBs and/or PRB beam groups.

[0038] The description relates in some respects to providing an adjustable traffic-to-pilot ratio (TPR) for throughput optimization. For example, devices might use different TPRs for different modulation and coding schemes (MCSs), classifications, and so on.

[0039] The various concepts presented throughout this description can be implemented across a wide variety of communication systems, network architectures, and communication standards. With reference to Figure 1, by way of example and without limitation, an illustrative access network 100 is illustrated. The access network 100 may be implemented in accordance with various network technologies including, without limitation, fifth generation technology (5G), fourth generation technology (4G), third generation technology (3G), and other architectures of network. Thus, various aspects of the description can be extended to networks based on Long Term Evolution (LTE), LTE-Advanced (LTE-A) (in FDD, TDD or both modes), Universal Mobile Telecommunications System (UMTS), Global System for Mobile Communications (GSM), Code Division Multiple Access (CDMA), Enhanced Evolution Data (EV-DO), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX) , IEEE 802.20, Ultra Wideband (UWB), Bluetooth, and/or other suitable systems. The actual telecommunications standard, network architecture and/or communication standard employed will depend on the specific application and design constraints imposed on the system as a whole.

[0040] The access network 100 includes multiple cellular regions (cells), including cells 102, 104 and 106, each of which may include one or more sectors. Cells can be defined geographically, for example by coverage area. In a cell that is divided into sectors, multiple sectors within a cell can be formed by groups of antennas with each antenna being responsible for communicating with ATs in one part of the cell. For example, in cell 102, antenna groups 112, 114 and 116 can each correspond to a different sector. In cell 104, antenna groups 118, 120 and 122 can each correspond to a different sector. In cell 106, groups of antennas 124, 126 and 128 may each correspond to a different sector.

[0041] Cells 102, 104 and 106 may include multiple access terminals (ATs) that may be in communication with one or more sectors of each cell 102, 104 or 106. For example, ATs 130 and 132 may be in communication with an access point (AP) 142, ATs 134 and 136 may be in communication with an AP 144, and ATs 138 and 140 may be in communication with an AP 146. In various implementations, an AP may be referred to as or implemented as a base station, a NodeB, an eNodeB, and so on; while an AT may be referred to as or implemented as a user equipment (UE), a mobile station, a remote wireless device, and so on.

[0042] Figure 2 is a block diagram of the system 200 including an access point (AP) 210 in communication with an access terminal (AT) 250, where the AP 210 and the AT 250 can be configured to provide the functionality as taught here. The AP 210 could be the AP 142, 144 or 146 in Figure 1, and the AT 250 could be the AT 130, 132, 134, 136, 138 or 140 in Figure 1. In various operational situations, the AP 210 and/or The AT 250 can be a transmitter or transmitting device, or a receiver or receiving device, or both. Examples of such transmitters, transmitting devices, receivers and receiving devices are illustrated in figures 1, 3, 5-8, 11, 13, 17 and 21.

[0043] In a downlink communication from the AP 210 to the AT 250, a controller or processor (controller/processor) 240 may receive data from a data source 212. The channel estimates may be used by the controller/processor 240 to determine the encoding, modulation, spreading, and/or encryption schemes to transmit processor 220. These channel estimates may be derived from a reference signal transmitted by AT 250 or from feedback from AT 250. A transmitter 232 may provide various functions of signal conditioning including amplification, filtering, and modulation frames on a carrier for downlink transmission over a wireless medium via antennas 234A-234N. Antennas 234A-234N can include one or more antennas, for example, including beam steering bidirectional adaptive antenna arrays, MIMO arrays, or any other suitable transmit/receive technology.

[0044] At the AT 250, a receiver 254 receives the downlink transmission through the antennas 252A-252N (eg, representing one or more antennas) and processes the transmission to retrieve the modulated information on the bearer. Information retrieved by receiver 254 is provided to a controller/processor 290. Controller/processor 290 decrypts and unscatters the symbols, and determines the most likely signal constellation points transmitted by the AP 210 based on the modulation scheme. These soft decisions may be based on channel estimates computed by controller/processor 290. The soft decisions are then decoded and deinterleaved to recover the data, control, and reference signals. The CRC codes are then checked to determine if the frames were successfully decoded. The data carried by the successfully decoded frames will then be provided to a data dump 272, which represents the applications running on the AT 250 and/or various user interfaces (eg monitor). The control signals carried by the successfully decoded frames will be provided to a controller/processor 290. When frames are unsuccessfully decoded, the controller/processor 290 may also utilize an acknowledgment protocol (ACK) and/or acknowledgment (NACK) to support retransmission requests for these frames.

[0045] In uplink from AT 250 to AP 210, data from a data source 278 and controller/processor control signals 290 are provided. Data source 278 may represent applications running on the AT 250 and various user interfaces (eg, keyboard). Similar to the functionality described with respect to downlink transmission by AP 210, controller/processor 290 provides various signal processing functions including CRC codes, encoding and interleaving to facilitate FEC, mapping into signal constellations, spreading with OVSFs, and encryption to produce a series of symbols. The channel estimates, derived by the controller/processor 290 from a reference signal transmitted by the AP 210 and the feedback contained in a midamble transmitted by the AP 210, can be used to select the appropriate encoding, modulation, spreading and/or encryption schemes . Symbols produced by controller/processor 290 will be used to create a frame structure. Controller/processor 290 creates this frame structure by multiplexing symbols with additional information, resulting in a series of frames. The frames are then provided to a transmitter 256, which provides various signal conditional functions including amplification, filtering and modulation of the frames on a bearer for uplink transmission over the wireless medium via antennas 252A-252N.

[0046] The uplink transmission is processed in the AP 210 in a similar way to that described with respect to the receiver function in the AT 250. A receiver 235 receives the uplink transmission through the antennas 234A-234N and processes the transmission to retrieve the information carrier modulated. Information retrieved by receiver 235 is provided to controller/processor 240, which analyzes each frame. The controller/processor 240 performs the inversion of the processing performed by the controller/processor 290 in the AT 250. The data and control signals carried by the successfully decoded frames can then be provided to a data dump 239. If any of the frames are decoded without success by the receiving processor, controller/processor 240 may also use a positive acknowledgment (ACK) and/or a negative acknowledgment (NACK) protocol to support retransmission requests for these frames.

[0047] The controller/processors 240 and 290 can be used to direct the operation on the AP 210 and on the AT 250, respectively. For example, controller/processors 240 and 290 can provide various functions including timing, peripheral interfaces, voltage regulation, power management and other control functions. The computer-readable medium of memories 242 and 292 can store the data and software for the AT 210 and AT 250, respectively.

[0048] In accordance with various aspects of the disclosure, an element or any part of an element, or any combination of elements may be implemented with controller/processors 240 and 290 (e.g., which may each include one or more processors). Controller/processors 240 and 290 are responsible for generating processing, including execution of software stored in memory 252 or 292. The software, when executed by controller/processors 240 and 290, causes controller/processors 240 and 290 to perform the various functions described below for any particular device. Memory 252 or 292 may also be used to store data that is manipulated by controller/processors 240 and 290 when running software.

[0049] In various aspects of the description, an apparatus can be used in a wireless communication network, as a programming entity (for example, the AP 210) and/or as a non-programming or subordinate entity (for example, the AT 250). Furthermore, in various aspects of the disclosure, an apparatus may employ wireless peer-to-peer (P2P) communication. For example, two or more P2P devices can cooperate to form an interwoven wireless communication network. In any case, the apparatus to communicate with one or more wireless entities via an air interface. In any wireless communication network, the channel conditions corresponding to the air interface will change over time.

[0050] Many networks, accordingly, utilize one or more rate control circuits to dynamically adapt to the channel. For example, a transmitting device can configure one or more transmission parameters, including but not limited to a modulation and coding scheme (MCS), a transmission energy, etc., to focus on a desired error rate in the transmitting device. receipt. The receiving device that is receiving a packet-swapped data stream typically verifies the integrity of the packets (for example, by using a cyclic redundancy check, or CRC, a checksum, a success/failure PHY layer channel, etc.) and can report back to the transmitting device using an acknowledgment or negative acknowledgment. This health check and reporting often, though not always, takes the form of an auto-repeat request (ARQ) and/or hybrid auto-repeat request (HARQ) algorithm. In other examples, any suitable algorithm or means of providing feedback or response transmissions from the receiving device to the transmitting device may be used, such as reports regarding channel quality.

[0051] In some network designs, DMRS pilots have a fixed standard in both time and frequency. this fixed pattern can result in loss of performance at the base station and the channel estimation per subframe. Additionally, there may be demodulation latency arising from this fixed pilot structure.

[0052] The description relates in some respects to techniques for enhanced channel estimation. In a first illustrative technique, a device (eg a base station) can specify a pilot structure where the pilot density differs with time. For example, a device can adapt DMRS pilot density over time to facilitate earlier pilot processing and thereby improve the decoding timeline for channel estimation. This technique can therefore be colloquially referred to as a "pilot bootstrap" technique. In a second illustrative technique, a device can indicate that a pilot from a previous transmission time slot (TTI) can be used for channel estimation. Accordingly, devices can employ DMRS cross-TTI bundling to improve channel estimation quality without significantly affecting the associated signaling overhead and/or processing overhead. In a third illustrative technique, a device may employ frequency domain physical resource (PRB) block bundling. In a fourth illustrative technique, a device may utilize an adjustable traffic-to-pilot ratio (TPR) for throughput optimization.

[0053] In some respects, these techniques can facilitate decision-directed/interactive extrapolation and channel estimation on a device (e.g., an access terminal) that receives pilots, thereby improving decoding performance and reducing latency of decoding. Accordingly, through the use of decision-driven and interactive channel estimations based on the teachings presented here, such a device can improve its channel estimation accuracy and latency compared to conventional schemes.

[0054] Each of the above four techniques will be described in turn with reference to figures 3 to 7. For purposes of illustration, these figures may illustrate various components in the context of channel estimation for DMRS pilot systems and/or LTE technology . It should be appreciated, however, that the teachings presented here may employ other types of devices and may be implemented using other types of radio technologies and architectures. Furthermore, various operations can be described as being performed by specific types of components (eg, eNBs, base stations, client devices, peer devices, UEs, and so on). It should be understood, however, that these operations may be performed by other types of devices. To reduce the complexity of these figures, only a few illustrative components are illustrated. It should be appreciated, however, that the teachings presented herein can be implemented using a different number of components or other types of components.

Pilot Structure

[0055] The description refers in some respects to a pilot structure where the density of pilots may vary over time.

[0056] Fig. 3 illustrates a communication system 300 where a base station (BS) 304 (e.g. an eNB) communicates pilot frame information and other information to a UE 302 in accordance with the teachings presented here. In the communication system 300, the UE 302 is served by the base station 304. In some aspects, the UE 302 may correspond to the AT 250 of Figure 2, or any of the ATS 130, 132, 134, 136, 138, or 140 of the Figure 1. In some aspects, base station 304 may correspond to AP 210 of Figure 2, or any of APs 142, 144, or 146 of Figure 1. UE 302 and base station 304 include respective transmitters 306 and 308 and receivers 310 and 312 to support communication via a downlink (DL) 314 and an uplink (UL) 316 as indicated. That is, UE 302 transmits UL signaling 318 to base station 304 and base station transmits DL signaling 320 to UE 302.

[0057] As mentioned above, it should be noted that the discussions of aspects of technology discussed in this description with respect to base stations and UEs serve the purpose of explanation. In other situations, the described base stations and UEs may instead be other types of components/devices capable of performing wireless communication. For example, the teachings can be applied between a wireless user device and a wireless network device, between multiple wireless user devices, or between multiple wireless network devices.

[0058] A pilot structure 400 of Figure 4 illustrates symbols in the time domain (x axis) and in the frequency domain (y axis). A transmission period 402 includes multiple TTIs (e.g., a first TTI 404). In some aspects, the transmission period 402 may correspond to a burst of data. Also, while three TTIs are illustrated in Figure 1 for illustration purposes, a transmission period can include a different number of TTIs.

[0059] Pilot symbols 406 (represented by shaded boxes) are defined at the beginning of each TTI. In some respects, this makes it easier to quickly detect the pilot symbols in each TTI.

[0060] Additionally, pilot symbols 408 (represented by shaded boxes) are provided in the first TTI in symbols 4 and 5. Additional pilot symbols may be provided in other symbols in other implementations (for example, in addition to or in addition to symbols pilot on symbols 4 and 5). Using additional symbols can increase pilot density (for example, at the beginning of a data burst). For example, after a cold start or a change in beamforming (BF), a base station can signal a UE to program denser pilots, bootstrapping the UE's channel estimate. The UE receives pilots sooner and can therefore generate a channel estimate sooner. Additionally, the UE can receive more pilot information sooner and therefore generate a more accurate estimate sooner. The UE is notified about the additional pilot symbols in that case via the indicator bits in the control channel payload. Accordingly, the UE channel estimation process is aided (colloquially referred to as bootstrapping) by providing the UE with previous pilots, etc.

[0061] The pilot density may be increased in terms of at least one of transmission time, frequency or energy. For example, more pilots can be sent on some TTIs rather than on other TTIs. As another example, additional pilots (e.g. previous pilots) may be transmitted on additional frequency bands (e.g. simultaneously or at different times). As another example, the transmit power may be higher for some pilots (eg past pilots) than for others.

[0062] Referring again to Fig. 3, based on one or more criteria, a processing circuit 322 of the base station 304 generates a pilot frame and transmits an indication of the pilot frame 326 to the UE 302. The base station 304 may also transmit an indication of whether the above TTIs can be used for decoding, PMIs for PRB bundling, and TPR indications as discussed below. At some point, the base station 304 also transmits pilots to the UE 302 according to the pilot structure.

[0063] A processing circuit 324 of the UE 302 uses a received pilot frame (derived from the received pilot frame indication and pilots 328) to receive pilots from the base station 304. The processing circuit 324 also generates a channel estimate 330 based on on the received pilots (from the received pilot frame indication and pilots 328) and decodes (e.g., demodulates) the received data based on the channel estimate. The UE 302 may also send the channel estimate 330 or parameters derived from the channel estimate to the base station 304 to allow the base station 304 to adapt communication parameters based on a received channel estimate 332.

[0064] As discussed herein, through the use of the dynamic pilot structure as taught here, the UE 302 can advantageously generate more accurate channel estimates and mitigate associated delays. For example, by receiving front-loaded pilots in a transmission period, UE 302 can generate a channel estimate more quickly and/or with greater accuracy. Furthermore, by receiving pilots before the end of a TTI, the UE 302 can generate a channel estimate immediately (eg, compared to LTE where the pilot is at the end of the TTI). Additionally, periodic pilot updates can be received and used to improve the channel estimation.

TTI Pilot Filtering

[0065] The description refers in some respects to the use of a pilot from a previous TTI for channel estimation. For example, a base station can signal a UE to use pilots in the previous TTI to improve channel estimation quality and decoding timeline. This technique can be used, for example, in cases where the TTI has not changed (for example, in cases where the beamforming has not changed between TTIs).

[0066] Fig. 5 illustrates a communication system 500 where a base station (BS) 504 communicates pilot information and other information as taught herein to a UE 502 in accordance with the teachings presented herein. In communication system 500, UE 502 is served by base station 504. In some aspects, UE 502 may correspond to AT 250 of Fig. 2, or any of ATs 130, 132, 134, 136, 138 or 140 of Fig. 1. In some aspects, base station 504 may correspond to AP 210 of Fig. 2, or any of APs 142, 144, or 146 of Fig. 1. UE 502 and base station 504 include respective transmitters 506 and 508 and receivers 510 and 512 to support communication via a downlink (DL) 514 and an uplink (UL) 516 as indicated. That is, UE 502 transmits UL signaling 518 to base station 504 and base station transmits DL signaling 520 to UE 502.

[0067] A processing circuit 522 of the base station 504 generates a TTI filtering indication 526 that indicates whether pilots from previous TTIs can be used for channel estimation for the current TTI. Base station 504 transmits this indication to UE 502. Additionally, at some point, base station 504 transmits pilots to UE 502 according to the current pilot structure.

[0068] A processing circuit 524 of the UE 502 receives the TTI filtering indication and pilots 528 and generates a channel estimate 530 based on the received pilots and the indicated filtering technique. Thus, in some cases, processing circuit 524 generates channel estimate 530 based on pilots from a current TTI and pilots from past TTIs. In some aspects, processing circuit 524 can decode (e.g., demodulate) received data based on the channel estimate. UE 502 also sends the channel estimate to base station 504 to allow processing circuitry 522 of base station 504 to adapt communication parameters based on a received channel estimate 532.

[0069] Through the use of dynamic pilot techniques taught here, UE 502 can advantageously generate more accurate channel estimates and mitigate associated delays. For example, by receiving pilots from previous TTIs, cane estimation accuracy or channel estimation time can be improved.

Bundling PRB

[0070] The description relates in some aspects to improved frequency domain pilot bundling. In some respects, this involves PRB bundling. Uniform pilot spacing can be employed in a bundled PRB region to allow for better channel estimation. Broadband bundling can be employed to trade off channel estimation performance for subband scheduling flexibility (SB) and/or beamforming gain (BF).

[0071] Wideband bundling in the presence of precoding shift can be employed to improve channel estimation quality. For example, a base station may transmit the signals to indicate a precoding matrix indicator (PMI) change over the PrB beams to allow joint wideband (WB) channel estimation across multiple PRB beams. In some implementations, a base station signals the difference between neighboring resource block (RB) PMIs. In some implementations, a base station performs wideband beamforming based on an audible reference signal (SRS) and subband fine tuning based on channel state feedback (CSF). UE-PMI can also be used to adjust precoder differences through PRBs. For example, subband PMI reported per UE can be applied with certainty N subframes later.

[0072] Fig. 6 illustrates a communication system 600 where a base station (BS) 604 communicates pilot information and other information as taught herein to a UE 602 in accordance with the teachings presented herein. In the communication system 600, the UE 602 is served by the base station 604. In some aspects, the UE 602 may correspond to the AT 250 of FIG. Figure 1. In some aspects, base station 604 may correspond to AP 210 of Figure 2 or any of APs 142, 144, or 146 of Figure 1. UE 602 and base station 604 include transmitters 606 and 608 and receivers 610 and 612 protocols to support communication via a downlink (DL) 614 and an uplink (UL) 616 as indicated. That is, UE 602 transmits UL signaling 618 to base station 604 and base station transmits DL signaling 620 to UE 602.

[0073] A processing circuit 622 of the base station 604 generates a PRB bundling indication 626 (eg, a PMI applied across different PRBs), which indicates, for example, how PRBs may be bundled. Base station 604 transmits this indication to UE 602. Additionally, at some point, base station 604 transmits pilots to UE 602 according to the current pilot structure.

[0074] A processing circuit 624 of the UE 602 receives the PRB framing indication and pilots 628 and generates a channel estimate 630 based on the received pilots and the indicated PRB framing scheme. Processing circuit 624 may also decode (eg, demodulate) the received data based on the channel estimate. UE 602 sends the channel estimate (or parameters derived from the channel estimate) to base station 604 to allow processing circuitry 622 of base station 604 to adapt communication parameters based on a received channel estimate 632.

[0075] Through the use of the dynamic pilot techniques taught here, the UE 602 can advantageously generate more accurate channel estimates and mitigate the associated delays. For example, by receiving pilots that are uniform across a PRB beam, UE 602 can generate a more accurate channel estimate (e.g., for a high-bandwidth channel).

TPR adjustment

[0076] The description refers in some respects to power optimization for a DMRS pilot. In some aspects, traffic ratio-to-flexible pilot (TPR) tuning can be employed to optimize DMRS traffic performance. For example, DMRS power can be optimized for different MCSs, ratings, rates, and so on. For that purpose, a first device (e.g. a base station) can signal a TPR to neighboring devices (e.g. UEs) for joint demodulation.

[0077] Fig. 7 illustrates a communication system 700 where a base station (BS) 704 communicates pilot information and other information as taught herein to a UE 702 in accordance with the teachings presented herein. In the communication system 700, the UE 702 is served by the base station 704. In some aspects, the UE 702 may correspond to the AT 250 of Fig. 2, or any of the ATs 130, 132, 134, 136, 138 or 140 of Fig. 1. In some aspects, base station 704 may correspond to AP 210 of Figure 2, or any of APs 142, 144, or 146 of Figure 1. UE 702 and base station 704 include transmitters 706 and 708 and receivers 710 and 712 protocols to support communication via a downlink (DL) 714 and an uplink (UL) 716 as indicated. That is, UE 702 transmits UL signaling 718 to base station 704 and base station transmits DL signaling 720 to UE 702.

[0078] At the same time, a processing circuit 722 of the base station 704 sends a TPR indication 726 to the UE 702 (e.g., by sending a suitable signal to the UE via downlink signaling 720). A processing circuit 724 of the UE 702 generates control signals 730 to control the transmit power of the transmitter 706 based on the received TPR indications (from the received TPR indication and pilots 728).

[0079] Processing circuit 724 also generates a channel estimate (not shown) based on received pilots (from received TPR indications and pilots 728). Transmitter 706 transmits this channel estimate (or parameters derived from the channel estimate) to receiver 712 via uplink 716. Accordingly, processing circuit 722 of base station 704 may adjust communication parameters based on an estimate of Received channel 732.

[0080] As discussed here, through the use of TPR indications, UE 702 can advantageously generate more accurate channel estimates and mitigate the associated delays. For example, UE 702 can dynamically configure its transmit power according to TPR information received from base station 704. In this way, different TPRs can be used for different transmission schemes (e.g., for different MCSs, different classifications, etc.) .).

[0081] The functionality described in two or more of figures 3, 5, 6 or 7 can be combined in some implementations. For example, a base station can include the functionality of two or more of the base station 304, the base station 504, the base station 604 or the base station 704. As another example, a UE can include the functionality of two or more of the UEs 302, 502, 602 or 702.

Illustrative Device

[0082] Figure 8 illustrates a block diagram of an illustrative hardware implementation of an apparatus 800 configured to communicate in accordance with one or more aspects of the description. For example, apparatus 800 may embody or be implemented within a base station (e.g., an eNB), a UE, or some other type of device that supports wireless communication. In various implementations, apparatus 800 may embody or be implemented within an access terminal, an access point, or some other type of device. In various implementations, apparatus 800 can embody or can be implemented within a mobile phone, a smartphone, a tablet, a laptop computer, a server, a personal computer, a sensor, an entertainment device, a vehicle component, medical devices , or any other electronic device having a circuitry.

[0083] The apparatus 800 includes a communication interface (e.g., at least one transceiver) 802, a storage medium 804, a user interface 806, a memory device (e.g., a memory circuit) 808 and a processing circuit (e.g., at least one processor) 810. In various implementations, user interface 806 may include one or more of: a keyboard, a monitor, a speaker, a microphone, a touch screen monitor, or some other set of circuitry for receiving input from or sending output to a user.

[0084] These components can be coupled to and/or located in electrical communication with each other through a signaling bus or other suitable component, usually represented by the connection lines in figure 8. The signaling bus connects several circuits together in a manner that each of the communication interface 802, the storage medium 804, the user interface 806 and the memory device 808 is coupled to and/or is in electrical communication with the processing circuit 810. The signal bus may also connect various other circuits (not shown) such as timing supplies, peripherals, voltage regulators and power management circuits, which are well known in the art and therefore will not be described further.

[0085] The communication interface 802 provides a means to communicate with other appliances via a transmission medium. In some implementations, communication interface 802 includes circuitry and/or programming adapted to facilitate bidirectional communication of information with respect to one or more communication devices on a network. In some implementations, the communication interface 802 is adapted to facilitate wireless communication from the apparatus 800. In these implementations, the communication interface 802 can be coupled to one or more antennas 812 as illustrated in Figure 8 for wireless communication within a wireless communication system. Communication interface 802 can be configured with one or more independent receivers and/or transmitters, in addition to one or more transceivers. In the illustrated example, the communication interface 802 includes a transmitter 814 and a receiver 816. The communication interface 802 serves as an example of a receiving medium and/or transmitting medium.

[0086] Memory device 808 may represent one or more memory devices. As indicated, memory device 808 may hold pilot-related information 818 along with other information utilized by apparatus 800. In some implementations, memory device 808 and storage medium 804 are implemented as a common memory component. Memory device 808 may also be used to store data that is manipulated by processing circuit 810 or some other component of apparatus 800.

[0087] Storage medium 804 may represent one or more computer-readable, machine-readable, and/or processor-readable devices for storing programming, such as code or processor-executable instructions (e.g., software, firmware) , electronic data, databases, or other digital information. Storage medium 804 can also be used for storing data that is manipulated by processing circuit 810 when executing the schedule. Storage medium 804 can be any available medium that can be accessed by a general or special purpose processor, including portable or fixed storage devices, optical storage devices, and various other media capable of storing, containing, or transporting programming.

[0088] By way of example and not limitation, storage medium 804 may include a magnetic storage device (e.g., hard disk, floppy disk, magnetic strip), an optical disk (e.g., a compact disk (CD ), or a digital versatile disk (DVD)), a smart card, a flash memory device (for example, a card, stick, or key drive), random access memory (RAM), read-only memory ( ROM), a programmable ROM (PROM), an erasable PROM (EPROM), an electrically eraseable PROM (EEPROM), a register, a removable disk, and any other suitable medium for storing software and/or instructions that can be accessed and read by a computer. Storage medium 804 may be embodied in an article of manufacture (e.g., a computer program product). By way of example, a computer program product may include a computer-readable medium in packaging materials. In view of the above, in some implementations, storage medium 804 may be a non-transient (eg, tangible) storage medium.

[0089] The storage medium 804 can be coupled to the processing circuit 810 so that the processing circuit 810 can read information from and write information to the storage medium 804. That is, the storage medium 804 can be coupled to processing circuitry 810 such that storage medium 804 is at least accessible by processing circuitry 810, including examples in which at least one storage medium is integral to processing circuitry 810 and/or examples where at least one storage medium is storage is separate from processing circuitry 810 (eg, resident in apparatus 800, outside apparatus 800, distributed across multiple entities, etc.).

[0090] Programming stored by storage medium 804, when executed by processing circuit 810, causes processing circuit 810 to perform one or more of the various functions and/or process operations described herein. For example, storage medium 804 may include operations configured to regulate operations on one or more hardware blocks of processing circuitry 810, in addition to utilizing communication interface 802 for wireless communication using their respective communication protocols.

[0091] Processing circuit 810 is generally adapted for processing, including the execution of, such programming stored on storage medium 804. As used herein, the terms "code" or "programming" should be considered broadly to include without limitation instructions, instruction sets, data, code, code segments, program code, programs, programming, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable elements, sequences procedures, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language or otherwise.

[0092] The processing circuit 810 is arranged to obtain, process and/or send data, access and store control data, issue commands, and control other desired operations. Processing circuitry 810 may include circuitry configured to implement the desired programming provided by the appropriate media in at least one instance. For example, processing circuit 810 can be implemented as one or more processors, one or more controllers, and/or other structure configured to execute executable programming. Examples of processing circuit 810 may include a general purpose processor, digital signal processor (DSP), application specific integrated circuit (ASIC), field programmable gate assembly (FPGA) or other programmable logic component, gate discrete or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor can include a microprocessor in addition to any conventional processor, controller, microcontroller, or state machine. Processing circuit 810 may also be implemented as a combination of computing components, such as a combination of a DSP and a microprocessor, a number of microprocessors, one or more microprocessors together with a DSP core, an ASIC and a microprocessor, or any other number of variable configurations. These examples of processing circuit 810 are for illustration, and other suitable configurations within the scope of the description are also contemplated.

[0093] In accordance with one or more aspects of the description, processing circuit 810 can be adapted to perform any or all of the features, processes, functions, operations, and/or routines for all or any of the apparatus described herein. For example, processing circuit 810 can be configured to perform any of the steps, functions, and/or processes described with respect to Figures 1-7 and 9-10. As used herein, the term "adapted" with respect to processing circuit 810 may refer to processing circuit 810 being one or more configured, employed, implemented, and/or programmed to perform a particular process, function, operation, and/or routine in accordance with various characteristics described herein.

[0094] Processing circuit 810 may be a specialized processor, such as an application-specific integrated circuit (ASIC) that serves as a means for (e.g., framework for) performing any of the operations described with respect to Figures 1 to 7 and 9 to 10. Processing circuit 810 serves as an example of a transmission medium and/or reception medium. In some implementations, processing circuit 810 incorporates the functionality of processing circuit 322 of Figure 3.

[0095] According to at least one example of the apparatus 800, the processing circuit 810 may include one or more of a circuit/module for determining a pilot structure 820, a circuit/module for transmission 822, or a circuit/module for changing a beamforming configuration 824. In some implementations, the circuit/module for determining a pilot structure 820, the circuit/module for transmitting 822, and the circuit/module for changing a beamforming configuration 824 correspond, at least in part, to the processing circuit 322 of Figure 3.

[0096] The circuit/module for determining a pilot frame 820 may include circuitry and/or programming (e.g. code for determining a pilot frame 826 stored on the storage medium 804) adapted to perform various functions relating to, for example example, determining a pilot frame where the pilot density differs with time within a transmission period. In some implementations, the circuit/module for determining a pilot frame 820 defines the pilot frame. For example, pilot frame determination circuit/module 820 may define a pilot frame where the pilot density is greater at an early part of the transmission period (e.g., the pilot density at an early part of the transmission period is greater than than the pilot density in a later part of the transmission period). As another example, pilot frame determination circuit/module 820 may define a pilot frame where the pilot density is different for different transmission time intervals (TTIs) within the transmission period. In some aspects, pilot density further differs with respect to frequency during the transmission period and/or with respect to transmission power during the transmission period. In some implementations, pilot frame determination circuit/module 820 obtains the pilot frame. For example, the pilot frame determination circuit/module 820 may obtain pilot frame information from an apparatus component (e.g., memory device 808, receiver 816, or some other component) or directly from a device (eg base station, user device, etc.) that broadcasts this information. The pilot frame determination circuit/module 820 sends the pilot frame information determined (e.g., stores the information in memory device 808 or sends the information to another apparatus component 800). In some implementations, a frame pilot 802 includes the frame determining circuit/module pilot 820 and/or the frame determining code pilot 826.

[0097] The circuit/module for transmission 822 may include circuitry and/or programming (for example, code for transmission 828 stored on storage medium 804) adapted to perform various functions related to, for example, transmission of an indication or other information. In some implementations, transmit circuit/module 822 is configured to transmit a pilot frame indication. Initially, the transmission circuit/module 822 obtains data to be transmitted. For example, transmission circuit/module 822 may obtain such data from an apparatus component (eg, memory device 808, pilot frame determination circuit/module 820, or some other component). In some implementations, transmission circuit/module 822 processes (eg, encodes) the data to be transmitted. The transmission circuit/module 822 then causes the data to be transmitted. For example, transmission circuit/module 822 may pass the data to transmitter 814 for subsequent radio frequency (RF) transmission. In some implementations, transmitter 814 includes circuitry/module to transmit 822 and/or code to transmit 828.

[0098] The circuit/module for changing a beamforming configuration 824 may include a set of circuitry and/or programming (e.g., code for changing a beamforming configuration 830 stored on storage medium 804) adapted to perform the various functions relating to, for example, changing a beamforming configuration used by the communication interface 802. Initially, the circuit/module for changing a beamforming configuration 824 receives an indication that a beamforming configuration must be changed. Additionally, the circuit/module for changing a beamforming configuration 824 obtains the parameters (e.g., from the memory device 808, the communication interface 802, or some other component) for the new beamforming configuration. These parameters may include, for example, an amplitude value and a phase value for each antenna subject to configuration. The circuit/module for changing a beamforming configuration 824 then generates, based on the obtained parameters, at least one control signal that controls at least one component (for example, an amplifier and/or a phase changer) of the transmitter 814 and/or receiver 816 to provide the desired beamforming when transmitter 814 transmits radio frequency (RF) signals and/or receiver 816 receives the RF signals.

[0099] As mentioned above, programming stored by storage medium 804, when executed by processing circuit 810, causes processing circuit 810 to perform one or more of the various functions and/or process operations described herein. For example, programming, when performed by processing circuit 810, can cause processing circuit 810 to perform the various functions, steps, and/or processes described herein with respect to Figures 1-7 and 9-10 at various times. Implementations As illustrated in FIG. 8, the storage medium 804 may include one or more of the code for determining a pilot frame 826, the code for transmitting 828, or the code for changing a beamforming configuration 830.

Illustrative Processes

[0100] Figure 9 illustrates a process 900 for communication in accordance with some aspects of the description. Process 900 may take place within a processing circuit (eg, processing circuit 810 of Fig. 8 ), which may be located in a base station, an access terminal, or some other suitable apparatus (device). In some implementations, process 900 represents operations performed by processing circuit 322 of Fig. 3. Obviously, in many respects within the scope of the description, process 900 may be implemented by any suitable apparatus capable of supporting communication-related operations.

[0101] In block 902, an apparatus (eg, a base station) determines a pilot structure where the pilot density differs with time within a transmission period. Thus, such a pilot structure can be used for advanced channel estimation (pilot bootstrapping) as discussed here.

[0102] In some aspects, the transmission period may correspond to a burst of traffic. In some aspects, the pilot frame may be for a demodulation reference signal (DMRS).

[0103] In some aspects, pilot density refers to at least one of: time, frequency, or transmission energy. For example, in some respects, the pilot density may differ with respect to the transmission power during the transmission period. As another example, in some respects pilot density may differ with respect to frequency during the transmission period.

[0104] In some aspects, pilots in the pilot structure may be located in an early part and/or a middle part of a transmission time slot (TTI). In some aspects, the pilot density may be greater than an early part of the transmission period (for example, the pilot density in an early part of the transmission period is greater than the pilot density in a later part of the transmission period). In some aspects, the pilot density can be different for different transmission time slots (TTIs) within the transmission period.

[0105] In some implementations, the circuit/module for determining a pilot structure 820 of Figure 8 performs the operations of block 902. In some implementations, the code for determining a pilot structure 826 of Figure 8 is executed to perform the operations from block 902.

[0106] In block 904, the apparatus transmits an indication of the pilot structure. For example, after establishing communication (or changing the beamforming) with a UE, an eNB may transmit that indication (for example, by broadcasting the indication or by unibroadcasting the indication to a UE). Thus, in some aspects, process 900 may involve changing a beamforming configuration, where the pilot structure is set as a result of changing (the alteration of) the beamforming configuration.

[0107] In some implementations, the circuit/module for transmission 822 of Figure 8 performs the operations of block 904. In some implementations, the code for transmitting 828 of Figure 8 is executed to perform the operations of block 904.

[0108] Figure 10 illustrates a process 1000 for communication in accordance with some aspects of the description. In some aspects, process 1000 may be implemented in conjunction with process 900 of Figure 9. For example, process 1000 may be, at least in part, a driver for block 902. Process 1000 may take place within a processing circuit (for example, processing circuit 810 of Fig. 8 ), which may be located in a base station, an access terminal, or some other suitable apparatus (device). In some implementations, process 1000 represents operations performed by processing circuit 322 of Fig. 3. Obviously, in many respects within the scope of the description, process 1000 may be implemented by any suitable apparatus capable of supporting communication operations.

[0109] In block 1002, an apparatus (eg, a base station) changes a beamforming configuration. For example, this change may be due to a change in channel conditions, movement of the apparatus and/or an associated apparatus, an obstruction, or some other condition.

[0110] In some implementations, the circuit/module for changing a beamforming configuration 824 of Figure 8 performs the operations of block 1002. In some implementations, the code for changing a beamforming configuration 830 of Figure 8 is executed to perform the operations of block 1002.

[0111] In block 1004, the apparatus sets a pilot structure (eg, as in block 902 above) as a result of the change in (the change of) beamforming structure in block 1002. For example, a specific pilot structure may be indicated for a given beamforming configuration in an attempt to provide the best possible communication quality.

[0112] In some implementations, the circuit/module for determining a pilot structure 820 of Figure 8 performs the operations of block 1004. In some implementations, the code for determining a pilot structure 826 of Figure 8 is executed to perform the operations of block 1004.

Illustrative Device

[0113] Figure 11 illustrates a block diagram of an illustrative hardware implementation of another apparatus 1100 configured to communicate in accordance with one or more aspects of the description. For example, apparatus 1100 may embody or be implemented within a UE, a base station (e.g., an eNB), or some other type of device that supports wireless communication. In various implementations, apparatus 1100 may embody or be implemented within an access terminal, an access point, or some other type of device. In various implementations, apparatus 1100 may embody or be implemented within a mobile phone, a smartphone, a tablet, a laptop computer, a server, a personal computer, a sensor, an entertainment device, a vehicle component, medical devices, or any other electronic device having circuit assemblies.

[0114] Apparatus 1100 includes a communication interface (for example, at least one transceiver) 1102, a storage medium 1104, a user interface 1106, a memory device 1108 (for example, storing pilot-related information 1118) , and a processing circuit (e.g., at least one processor) 1110. In various implementations, user interface 1106 may include one or more of a keyboard, monitor, speaker, microphone, screen monitor, touch, of some other circuitry for receiving an input from or sending an output to a user. The communication interface 1102 can be coupled to one or more antennas 1112, and can include a transmitter 1114 and a receiver 1116. In general, the components of figure 11 can be similar to the corresponding components of the apparatus 800 of figure 8.

[0115] In accordance with one or more aspects of the description, the processing circuit 1110 can be adapted to perform all or any of the features, processes, functions, operations and/or routines for all or any of the apparatus described herein. For example, processing circuit 1110 can be configured to perform any of the steps, functions, and/or processes described with respect to Figures 1 through 7 and 12. As used herein, the term "adapted" with respect to the processing circuit 1110 may refer to processing circuitry 1110 being one or more configured, employed, implemented, and/or programmed to perform a particular process, function, operation, and/or routine in accordance with various characteristics described above.

[0116] The processing circuit 1110 may be a specialized processor, such as an application-specific integrated circuit (ASIC) that serves as a means for (e.g., framework for) performing any of the operations described in conjunction with the figures of 1 to 7 and 12. Processing circuit 1110 serves as an example of a means for transmitting and/or a means for receiving. In some implementations, processing circuit 1110 incorporates the functionality of processing circuit 324 of Figure 3.

[0117] According to at least one example of the apparatus 1100, the processing circuit 1110 may include one or more of a circuit/module for receiving 1120, a circuit/module for generating a channel estimate 1122, or a circuit/module for module for decoding 1124. In some implementations, circuitry/module for receiving 1120, circuitry/module for generating a channel estimate 1122, and circuitry/module for decoding 1124 correspond, at least in part, to circuitry for processing 324 from figure 3.

[0118] The circuit/module for receiving 1120 may include circuitry and/or programming (for example, code for receiving 1126 stored on storage medium 1104) adapted to perform the various functions related to, for example, receiving of information. In some implementations, circuit/module for receiving 1120 is configured to receive an indication from a pilot frame. In some implementations, receiving circuit/module 1120 is configured to receive a pilot according to an indicated pilot structure. Initially, receiving circuit/module 1120 obtains information. For example, the receiving circuit/module 1120 may obtain this information from a device component (e.g., receiver 1116, memory device 1108, or some other component) or directly from a device (e.g., a base station). , a user device, etc.) that transmitted the information. In some implementations, receiving circuit/module 1120 identifies a location on memory device 1108 or some other component and invokes a read from that location to receive the information. In some implementations, receiving circuit/module 1120 processes (eg, decodes) the received information. Receiver circuit/module 1120 then sends the received information (eg, stores the information in memory device 1108 or sends the information to another device component 1100). In some implementations, receiver 1116 includes receive circuit/module 1120 and/or receive code 1126.

[0119] The circuit/module for generating a channel estimate 1122 may include a set of circuits and/or programming (for example, code for generating a channel estimate 1128 stored on the storage medium 1104) adapted to perform various functions relating to, for example, generating a channel estimate based on received information (eg, a received pilot). Initially, the circuit/module for generating a channel estimate 1122 obtains the received information. For example, the circuit/module for generating a channel estimate 1122 may obtain that information from a device component (e.g., the memory device 1108, the receiver 1116, the circuit/module for receiving 1120, or some other component). ) or directly from a device (eg base station, user device, etc.) that transmits this information. The channel estimation circuit/module 1122 then estimates the channel over which the information was received based on known information about the originally transmitted information in addition to transmitter and receiver parameters. Finally, channel estimation circuit/module 1122 sends the channel estimate to an apparatus component 1100 (e.g., memory device 1108, decoding circuit/module 1124, or some other component). In some implementations, the communication interface 1102 includes the circuitry/module for generating a channel estimate 1122 and/or the code for generating a channel estimate 1128.

[0120] The decoding circuit/module 1124 may include circuitry and/or programming (e.g., decoding code 1130 stored on storage medium 1104) adapted to decode the data of a TTI before the end of the TTI. Initially, the decoding circuit/module 1124 obtains the received information. For example, the decoding circuit/module 1124 may obtain this information from a component of the apparatus 1100 (e.g., the memory device 1108, the receiver 1116, the receiving circuit/module 1120, or some other component) or directly from a device (eg base station, user device, etc.) that transmitted the information. In some implementations, decoding circuit/module 1124 identifies a memory location of a value on memory device 1108 and invokes a read from that location. In any case, the decoding circuit/module 1124 starts processing the received information for a given TTI before the end of the TTI. For example, decoding circuit/module 1124 can process a pilot that is received at or near an early or middle section of the TTI without waiting for the entirety of the TTI to be received. Decoding circuit/module 1124 then sends the decoded information to a component of apparatus 1100 (e.g., memory device 1108 or some other component). In some implementations, receiver 1116 includes decoding circuit/module 1124 and/or decoding code 1130.

[0121] As mentioned above, programming stored by storage medium 1104, when executed by processing circuit 1110, causes processing circuit 1110 to perform one or more of the various functions and/or process operations described herein. For example, programming, when performed by processing circuit 1110, can cause processing circuit 1110 to perform the various functions, steps, and/or processes described herein with respect to Figures 1 through 7 and 12 in various implementations. As illustrated in Figure 11, storage medium 1104 may include one or more of code for receiving 1126, code for generating a channel estimate 1128, or code for decoding 1130.

Illustrative Process

[0122] Figure 12 illustrates a process 1200 for communicating in accordance with some aspects of the description. In some aspects, process 1200 may be complementary to process 900 of Fig. 9. Process 1200 may occur within a processing circuit (e.g., processing circuit 1110 of Fig. 11), which may be located in a base station. , a terminal and access, or some other suitable apparatus. In some implementations, process 1200 represents operations performed by processing circuit 324 of Fig. 3. Obviously, in many respects within the scope of the description, process 1200 may be implemented by any suitable apparatus capable of supporting communication operations.

[0123] In block 1202, an apparatus (e.g., a UE) receives an indication of a pilot frame where the pilot density differs with time within a transmission period. For example, a UE may receive an indication transmitted by an eNB (for example, as discussed above in conjunction with block 904 of Fig. 9 ).

[0124] In some aspects, pilot density refers to at least one of transmission time, frequency or energy. In some aspects, the pilot density is greater in an early part of the transmission period (for example, the pilot density in an early part of a transmission period is greater than the pilot density in a later part of the transmission period).

[0125] In some implementations, the circuit/module for receiving 1120 of Figure 11 performs the operations of block 1202. In some implementations, the code for receiving 1126 of Figure 11 is executed to perform the operations of block 1202.

[0126] In block 1204, the apparatus receives a pilot according to the indicated pilot structure. For example, a UE may receive a pilot that was transmitted at a time and/or frequency specified by the indicated pilot structure. In some aspects, the pilot may be a demodulation reference signal (DMRS). In some aspects, pilots in the pilot structure are located in an early part and/or a middle part of a transmission time slot (TTI).

[0127] In some implementations, the circuit/module for receiving 1120 of Figure 11 performs the operations of block 1204. In some implementations, the code for receiving 1126 of Figure 11 is executed to perform the operations of block 1204.

[0128] In block 1206, the apparatus generates a channel estimate based on the received pilot. In some aspects, the apparatus generates the channel estimate based on a pilot received prior to an end of the TTI.

[0129] In some implementations, the circuit/module for generating a channel estimate 1122 of Figure 11 performs the operations of block 1206. In some implementations, the code for generating a channel estimate 1128 of Figure 11 is executed to perform the block 1206 operations.

[0130] In option block 1208, the device can decode the TTI data before the end of the TTI. In some aspects, this decoding may be based on the channel estimate generated in block 1206.

[0131] In some implementations, the decoding circuit/module 1124 of Figure 11 performs the operations of block 1208. In some implementations, the decoding code 1130 of Figure 11 is executed to perform the operations of block 1208.

Illustrative Device

[0132] Figure 13 illustrates a block diagram of an illustrative hardware implementation of another apparatus 1300 configured to communicate in accordance with one or more aspects of the description. For example, apparatus 1300 may embody or be implemented within a base station (e.g., an eNB), a UE, or some other type of device that supports wireless communication. In various implementations, apparatus 1300 may embody or be implemented within an access terminal, an access point, or some other type of device. In various implementations, apparatus 1300 can embody or be implemented within a mobile phone, a smartphone, a tablet, a laptop computer, a server, a personal computer, a sensor, an entertainment device, a vehicle component, medical devices, or any other electronic device having a set of circuits.

[0133] The apparatus 1300 includes a communication interface (for example, at least one transceiver) 1302, a storage medium 1304, a user interface 1306, a memory device 1308 (for example, storing pilot-related information 1318) , and a processing circuit (e.g., at least one processor) 1310. In various implementations, user interface 1306 may include one or more of a keyboard, a monitor, a speaker, a microphone, a screen monitor, touch, or some other set of circuitry for receiving input from or sending output to a user. The communication interface 1302 may be coupled to one or more antennas 1312, and may include a transmitter 1314 and a receiver 1316. In general, the components of Figure 13 may be similar to the corresponding components of apparatus 800 of Figure 8.

[0134] In accordance with one or more aspects of the description, the processing circuit 1310 can be adapted to perform all or any of the features, processes, functions, operations and/or routines for all or any of the apparatus described herein. For example, processing circuit 1310 can be configured to perform any of the steps, functions, and/or processes described with respect to Figures 1-7 and 14-16. As used herein, the term "adapted" with respect to processing circuit 1310 may refer to processing circuit 1310 being one or more configured, employed, implemented, and/or programmed to perform a particular process, function, operation, and/or routine in accordance with various characteristics described herein.

[0135] The processing circuit 1310 may be a specialized processor, such as an application-specific integrated circuit (ASIC) that serves as a means for (e.g., framework for) performing any of the operations described in conjunction with FIGS. 7 and 14 to 16 . Processing circuit 1310 serves as an example of a means for transmitting and/or a means for receiving. In various implementations, processing circuit 1310 may incorporate the functionality of processing circuit 522 of Figure 5, processing circuit 622 of Figure 6, or processing circuit 722 of Figure 7.

[0136] According to at least one example of the apparatus 1300, the processing circuit 1310 may include one or more of a circuit/module for determining that a pilot structure is specified for successive TTIs 1320, a circuit/module for transmitting 1322 , a circuit/module for identifying a PRB beam 1324, a circuit/module for selecting a pilot frame 1326, or a circuit/module for determining TPR 1328. In various implementations, the circuit/module for determining that a frame pilot is specified for successive TTIs 1320, the circuit/module for transmission 1322, the circuit/module for identifying a PRB bundle 1324, the circuit/module for selecting a pilot structure 1326, and the circuit/module for determining TPR 1328 may correspond, at least in part, to the processing circuit 522 of figure 5, the processing circuit 622 of figure 6, or the processing circuit 722 of figure 7.

[0137] The circuitry/module for determining that a pilot structure is specified for successive TTIs 1320 may include circuitry and/or programming (e.g., code for determining that a pilot structure is specified for successive TTIs 1330 stored in storage medium 1304) adapted to perform various functions relating to, for example, determining that a particular pilot frame is specified for successive transmission time intervals (TTIs). Initially, the circuit/module for determining that a pilot structure is specified for successive TTIs 1320 obtains information indicating that successive TTIs are similar (e.g., from memory device 1308, communication interface 1302, or some other component of the 1300 apparatus). For example, the information may indicate that the communication interface 1302 will be using the same beamforming configuration for successive TTIs. The circuit/module for determining that a pilot structure is specified for successive TTIs 1320 can determine, based on the information, whether the pilot structure of successive TTIs will be the same. The circuit/module for determining that a pilot structure is specified for successive TTIs 1320 can thus decide whether a receiving device may use a pilot from an earlier TTI for channel estimation associated with a later TTI. Additionally, the circuit/module for determining that a pilot frame is specified for successive TTIs 1320 sends a determination indication (e.g., whether the same pilot frame is used for successive TTIs and/or whether a pilot from a previous TTI can be used for channel estimation) to a device component 1300 (e.g., memory device 1308, transmitter 1314, transmission circuit/module 1322, or some other component).

[0138] The circuit/module for transmission 1322 may include circuitry and/or programming (for example, code for transmission 1332 stored on storage medium 1304) adapted to perform various functions related to, for example, transmission of an indication or other information. In some implementations, transmit circuit/module 1322 is configured to transmit an indication that a pilot from a previous TTI can be used for channel estimation. In some implementations, transmit circuit/module 1322 is configured to transmit an indication of a selected pilot frame. In some implementations, transmitting circuit/module 1322 is configured to transmit an indication of a traffic-to-pilot ratio. Initially, the transmission circuit/module 1322 obtains data to be transmitted. For example, the circuit/module for transmission 1322 may obtain such data from an apparatus component (e.g., the memory device 1308, the circuit/module for determining that a pilot structure is specified for successive TTIs 1320, the circuit/module for module to select a 1326 pilot structure, the circuit/module to determine a 1328 TPR, or some other component). In some implementations, transmission circuit/module 1322 processes (eg, encodes) the data to be transmitted. The transmission circuit/module 1322 then causes the data to be transmitted. For example, transmission circuit/module 1322 may pass the data to transmitter 1314 for subsequent radio frequency (RF) transmission. In some implementations, transmitter 1314 includes transmit circuit/module 1322 and/or transmit code 1332.

[0139] The circuit/module for identifying a PRB 1324 beam may include a set of circuits and/or programming (for example, code for identifying a PRB 1334 beam stored on the storage medium 1304) adapted to perform various functions related to , for example, identifying a physical resource block (PRB) bundle that includes at least one PRB. Initially, the PRB beam identification circuit/module 1324 obtains information regarding resource requirements for future communications (e.g., based on information stored in memory device 1308, received from communication interface 1302 or some other component). The PRB beam identification circuit/module 1324 then selects a PRB beam (eg, a wideband beam) to be used for this communication based on the PRB Bundle operations discussed above. The PRB beam identification circuit/module 1324 then sends an indication of the identified PRB beam to an apparatus component 1300 (e.g., memory device 1308, pilot frame selection circuit/module 1326, or some other component).

[0140] The circuit/module for selecting a pilot structure 1326 may include a set of circuits and/or programming (for example, code for selecting a pilot structure 1336 stored in the storage medium 1304) adapted to perform various related functions, for example, selecting a pilot structure based on an identified PRB beam. Initially, the circuit/module for selecting a pilot frame 1326 obtains information regarding a PRB beam to be used for future communications (e.g., from the memory device 1308, the circuit/module for identifying a PRB beam 1324, or some other component). Pilot frame selection circuit/module 1326 then selects a pilot frame to be used for this communication that accommodates the PRB beam. For example, pilot frame selection circuit/module 1326 may specify a pilot frame with pilots evenly spread across a PRB beam with wideband communication. Pilot frame selection circuit/module 1326 then sends an indication of the pilot frame selected to an apparatus component 1300 (e.g., memory device 1308, transmitter 1314, transmission circuit/module 1322, or some other component).

[0141] The circuit/module for determining TPR 1328 may include circuitry and/or programming (for example, a module for determining TPR 1338 stored on storage medium 1304) adapted to perform various functions related to, for example, determination of a traffic-to-pilot ratio (TPR) for demodulation of reference signals (DMRSs). Initially, the TPR determining circuit/module 1328 obtains information regarding channel conditions (e.g., from memory device 1308, communication interface 1302, or some other component). The TPR determination circuit/module 1328 then selects /TPR based on these channel conditions. For example, the TPR determination circuit/module 1328 may select a TPR to correspond to a particular SNR target, error rate target, or some other communication factor. In particular, the circuit/module for determining a TPR 1328 can optimize DMRS power for different MCSs, ratings, rates, and so on. The TPR determining circuit/module 1328 then sends an indication of the determined TPR to an apparatus component 1300 (e.g., memory device 1308, transmitter 1314, transmission circuit/module 1322, or some other component) .

[0142] As mentioned above, programming stored by storage medium 1304 when executed by processing circuit 1310 causes processing circuit 1310 to perform one or more of the various functions and/or process operations described herein. For example, programming, when performed by processing circuit 1310, can cause processing circuit 1310 to perform the various functions, steps, and/or processes described herein with respect to Figures 1-7 and 14-16 in various implementations. . As illustrated in FIG. 13, the storage medium 1304 may include one or more of the code for determining that a pilot structure is specified for successive TTIs 1330, the code for transmitting 1332, the code for identifying a PRB beam 1334, the code for select a pilot structure 1336, or the code to determine a TPR 1338.

Illustrative Processes

[0143] Figure 14 illustrates a process 1400 for communicating in accordance with some aspects of the description. In some implementations, process 1400 may be performed in addition to (e.g., in conjunction with) process 900 of Fig. 9. Process 1400 may occur within a processing circuit (e.g., processing circuit 1310 of Fig. 13), which may be located in a base station, an access terminal, or some other suitable apparatus. In some implementations, process 1400 represents operations performed by processing circuit 522 of Fig. 5. Obviously, in many respects within the scope of the description, process 1400 may be implemented by any suitable apparatus capable of supporting communication operations.

[0144] In block 1402, an apparatus (eg, a base station) determines that a particular pilot frame is specified for successive transmission time intervals (TTIs). That is, the apparatus determines that the pilot structures for successive TTIs are the same. For example, an eNB may determine that the beamforming has not (or has not yet) changed from one TTI to the next, and consequently the pilot structure will not (or will not) change.

[0145] In some implementations, the circuit/module for determining that a pilot structure is specified for successive TTIs 1320 of Fig. 13 performs the operations of block 1402. In some implementations, the code for determining that a pilot structure is specified for successive TTIs 1330 of Figure 13 is executed to perform the operations of block 1402.

[0146] In block 1404, the apparatus transmits an indication that a pilot from a previous TTI can be used for channel estimation. In some aspects, the apparatus transmits this indication as a result of determining block 1402. In an illustrative implementation, an eNB may transmit this indication (eg, by broadcasting the indication or by unicasting the indication to a UE). In some aspects, the pilot may be a demodulation reference signal (DMRS).

[0147] In some implementations, the circuit/module for transmission 1322 of Figure 13 performs the operations of block 1404. In some implementations, the code for transmission 1332 of Figure 13 is executed to perform the operations of block 1404.

[0148] Figure 15 illustrates a process 1500 for communication in accordance with some aspects of the description. In some implementations, process 1500 may be performed in addition to (e.g., in conjunction with) process 900 of Fig. 9. Process 1500 may occur within a processing circuit (e.g., processing circuit 1310 of Fig. 13), which may be located in a base station, an access terminal, or some other suitable device. In some implementations, process 1500 represents operations performed by processing circuit 622 of Figure 6. Obviously, in many respects within the scope of the description, process 1500 may be implemented by any suitable apparatus capable of supporting communication operations.

[0149] In block 1502, an apparatus (eg, a base station) identifies a Physical Resource Block (PRB) beam. The PRB bundle includes at least one PRB.

[0150] In some implementations, the circuit/module for identifying a PRB beam 1324 of figure 13 performs the operations of block 1502. In some implementations, the code for identifying a PRB beam 1334 of figure 13 is executed to perform the operations of block 1502.

[0151] In block 1504, the apparatus selects a pilot structure based on the identified PRB beam. In some aspects, pilot structure selection includes selecting spacing for pilots based on a PRB beam bandwidth. In some aspects, the pilot structure is for demodulating reference signals (DMRSs). In various situations, the selected pilot structure may be the same as or different from the pilot structure determined in block 902 of Fig. 9 (for example, the selected pilot structure may be another pilot structure).

[0152] In some implementations, the circuit/module for selecting a pilot structure 1326 of figure 13 performs the operations of block 1504. In some implementations, the code for selecting a pilot structure 1336 of figure 13 is executed to perform the operations of block 1504.

[0153] In block 1506, the apparatus transmits an indication of the selected pilot structure (for example, the other selected pilot structure). For example, the apparatus may broadcast the indication or unicast the indication to a UE. In some aspects, the indication may be a precoding matrix (PMI) indicator. In some respects, the indication indicates a difference between neighboring resource block (RB) PMIs.

[0154] In some implementations, the circuit/module for transmission 1322 of Figure 13 performs the operations of block 1506. In some implementations, the code for transmitting 1332 of Figure 13 is executed to perform the operations of block 1506.

[0155] Fig. 16 illustrates a process 1600 for communicating in accordance with some aspects of the description. In some implementations, process 1600 may be performed in addition to (e.g., in conjunction with) process 900 of Fig. 9. Process 1600 may occur within a processing circuit (e.g., processing circuit 1310 of Fig. 13), which may be located in a base station, an access terminal, or some other suitable apparatus. In some implementations, process 1600 represents operations performed by processing circuit 722 of Fig. 7. Obviously, in many respects within the scope of the description, process 1600 may be implemented by any suitable apparatus capable of supporting communication operations.

[0156] In block 1602, an apparatus (eg, a base station) determines a traffic ratio to pilot (TPR) for the demodulation of reference signals (DMRSs). In some respects, the TPR is determined based on at least one of: a modulation and coding scheme (MCS), a classification, or a rate.

[0157] In some implementations, the circuit/module for determining a TPR 1328 of figure 13 performs the operations of block 1602. In some implementations, the code for determining a TPR 1338 of figure 13 is executed to perform the operations of block 1602 .

[0158] In block 1604, the apparatus transmits a TPR indication. For example, the apparatus may broadcast the indication or unicast the indication to a UE.

[0159] In some implementations, the circuit/module for transmission 1322 of Figure 13 performs the operations of block 1604. In some implementations, the code for transmission 1332 of Figure 13 is executed to perform the operations of block 1604.

Illustrative Device

[0160] Figure 17 illustrates a block diagram of an illustrative hardware implementation of another apparatus 1700 configured to communicate in accordance with one or more aspects of the description. For example, apparatus 1700 may embody or be implemented within a UE, a base station (e.g., an eNB), or some other type of device that supports wireless communication. In various implementations, apparatus 1700 may embody or be implemented within an access terminal, an access point, or some other type of device. In various implementations, apparatus 1700 may embody or be implemented within a mobile phone, a smartphone, a tablet, a laptop computer, a server, a personal computer, a sensor, an entertainment device, a vehicular component, a medical device, or any other electronic device having a set of circuits.

[0161] The apparatus 1700 includes a communication interface (e.g., at least one transceiver) 1702, a storage medium 1704, a user interface 1706, a memory device 1708 (e.g., storing pilot-related information 1718 ), and a processing circuit (e.g., at least one processor) 1710. In various implementations, user interface 1706 may include one or more of: a keyboard, a monitor, a speaker, a microphone, a video monitor, touch screen, some other circuitry for receiving an input from or sending an output to a user. The communication interface 1702 may be coupled to one or more antennas 1712, and may include a transmitter 1714 and a receiver 1716. In general, the components of Figure 17 may be similar to the corresponding components of apparatus 800 of Figure 8.

[0162] In accordance with one or more aspects of the description, the processing circuit 1710 can be adapted to perform any or all of the features, processes, functions, operations and/or routines for all or any of the apparatus described herein. For example, processing circuit 1710 can be configured to perform any of the steps, functions, and/or processes described with respect to Figures 1-7 and 18-20. As used herein, the term "adapted" with respect to the circuit Processing circuit 1710 may refer to processing circuitry 1710 being one or more configured, employed, implemented, and/or programmed to perform a particular process, function, operation, and/or routine in accordance with various characteristics described herein.

[0163] The processing circuit 1710 may be a specialized processor, such as an application-specific integrated circuit (ASIC) that serves as a means for (e.g., framework for) performing any of the operations described in conjunction with the figures of 1 to 7 and 18 to 20. Processing circuit 1710 serves as an example of a transmitting medium and/or a receiving means. In various implementations, processing circuit 1710 may incorporate the functionality of processing circuit 524 of Figure 5, processing circuit 624 of Figure 6, or processing circuit 724 of Figure 7.

[0164] According to at least one example of the apparatus 1700, the processing circuit 1710 may include one or more of a circuit/module for receiving 1720, a circuit/module for generating a channel estimate 1722, a circuit/module for for selecting a transmit power 1724, or a circuit/module for transmitting 1726. In various implementations, the circuit/module for receiving 1720, the circuit/module for generating a channel estimate 1722, the circuit/module for selecting a transmission power 1724, or the circuit/module for transmission 1726 may correspond, at least in part, to the processing circuit 524 of Fig. 5, the processing circuit 624 of Fig. 6, or the processing circuit 724 of Fig. 7.

[0165] The circuit/module for receiving 1720 may include circuitry and/or programming (for example, code for receiving 1728 stored on storage medium 1704) adapted to perform the various functions related to, for example, receiving information . In some implementations, receiving circuit/module 1720 is configured to receive an indication that a pilot from a previous TTI can be used for channel estimation. In some implementations, the receiving circuit/module 1720 is configured to receive TTIs. In some implementations, receiver circuit/module 1720 is configured to receive an indication of a selected pilot frame based on a PRB beam. In some implementations, receive circuit/module 1720 is configured to receive a pilot in accordance with an indication received from a pilot structure. In some implementations, receiver circuit/module 1720 is configured to receive an indication of a TPR for DMRSs. Initially, receiving circuit/module 1720 obtains information. For example, the receiving circuit/module 1720 may obtain this information from a device component (e.g., memory device 1708, receiver 1716, or some other component) or directly from a device (e.g., a base station, a user device, etc.) that transmitted the information. In some implementations, receiving circuit/module 1720 identifies a location on memory device 1708 or some other component and invokes a read from that location to receive the information. In some implementations, receiving circuit/module 1720 processes (eg, decodes) the received information. Circuit/module for receiving 1720 then sends the received information to an apparatus component 1700 (e.g., memory device 1708, circuit/module for generating a channel estimate 1722, circuit/module for selecting an energy transmission 1724, or some other component). In some implementations, receiver 1716 includes receive circuit/module 1720 and/or receive code 1728.

[0166] The circuit/module for generating a channel estimate 1722 may include a set of circuits and/or programming (for example, code for generating a channel estimate 1730 stored in the storage medium 1708) adapted to perform various functions concerning, for example, the generation of a channel estimate based on the received information. In some implementations, channel estimation circuit/module 1722 is configured to generate a channel estimation for decoding data from a second TTI based, at least in part, on a pilot from a first TTI. In some implementations, channel estimation circuit/module 1722 is configured to generate a channel estimation based on a received pilot. Initially, the channel estimate generation circuit/module 1722 obtains the received information (e.g., pilot information). For example, channel estimation circuit/module 1722 may obtain that information from an apparatus component (e.g., memory device 1708, receiver 1716, receive circuit/module 1720, or some another component), or directly from a device (for example, a base station, a user device, etc.) that transmits this information. Channel estimate generation circuit/module 1722 then estimates the channel over which the information was received based on known information about the originally transmitted information plus transmitter and receiver parameters. Finally, the channel estimate generation circuit/module 1722 sends the channel estimate (e.g., stores the channel estimate information in memory device 1708 or sends the information to another device component 1700). In some implementations, communication interface 1702 includes circuit/module for generating a channel estimate 1722 and/or code for generating a channel estimate 1730.

[0167] The circuit/module for selecting a transmission energy 1724 may include a set of circuits and/or programming (for example, code for selecting a transmission energy 1732 stored on the storage medium 1704) adapted to perform the various functions relating to, for example, selecting a transmit power based on a traffic-to-pilot ratio (TPR) for demodulating reference signals (DMRSs). Initially, the circuit/module for selecting a transmit power 1724 obtains a TPR indication (e.g., from memory device 1708, receiver 1716, circuit/module for receiving 1720, or some other component). of a transmit power 1724 then selects a transmit power based on the TPR and other power related information (e.g., pilot power). Finally, the transmit power selection circuit/module 1724 sends an indication of the selected transmit power to an apparatus component 1700 (e.g., memory device 1708, transmitter 1714, transmit circuit/module 1726, or some other component).

[0168] The circuit/module for transmission 1726 may include a set of circuits and/or programming (for example, code for transmission 1734 stored in the storage medium 1704) adapted to perform various functions related to, for example, transmission of signals from according to a selected transmit power. Initially, transmission circuit/module 1726 obtains data to be transmitted and an indication of a selected transmission power. For example, the transmission circuit/module 1726 may obtain such data and indication from an apparatus component (e.g., memory device 1708, transmission energy selection circuit/module 1732, or some other component). In some implementations, the transmission circuit/module 1726 processes (eg, encodes) the data to be transmitted. The transmission circuit/module 1726 then causes the data to be transmitted at the indicated transmission power. For example, transmit circuit/module 1726 may pass the data and transmit power indication to transmitter 1714 for subsequent radio frequency (RF) transmission. In some implementations, transmitter 1714 includes a transmit circuit/module 1726 and/or a transmit code 1734.

[0169] As mentioned above, programming stored by storage medium 1704, when executed by processing circuit 1710, causes processing circuit 1710 to perform one or more of the various functions and/or process operations described herein. For example programming, when performed by processing circuit 1710, can cause processing circuit 1710 to perform the various functions, steps, and/or processes described herein with respect to Figures 1-7 and 18-20 in various implementations. As illustrated in Figure 17, storage medium 1704 may include one or more of code for receiving 1728, code for generating a channel estimate 1730, code for selecting a transmit power 1732, or code for broadcast 1734.

Illustrative Processes

[0170] Figure 18 illustrates a process 1800 for communicating in accordance with some aspects of the description. In some implementations, process 1800 may be performed in addition to (e.g., in conjunction with) process 1200 of Fig. 12. Process 1800 may occur within a processing circuit (e.g., processing circuit 1710 of Fig. 17), which may be located in an access terminal, a base station, or some other suitable device. In some implementations, process 1800 represents operations performed by processing circuit 524 of Figure 5. Obviously, in many respects within the scope of the description, process 1800 may be implemented by any suitable apparatus capable of supporting communication operations.

[0171] In block 1802, an apparatus (e.g., a UE) receives an indication that a pilot from a previous transmission time slot (TTI) can be used for channel estimation. For example, a UE may receive an indication transmitted by an eNB (for example, as discussed above in conjunction with block 1404 of Fig. 14 ).

[0172] In some implementations, the circuit/module for receiving 1720 of Figure 17 performs the operations of block 1802. In some implementations, the code for receiving 1728 of Figure 17 is executed to perform the operations of block 1802.

[0173] In block 1804, the apparatus receives during a first TTI. For example, the apparatus may receive a first TTI of a frame.

[0174] In some implementations, the circuit/module for receiving 1720 of Figure 17 performs the operations of block 1804. In some implementations, the code for receiving 1728 of Figure 17 is executed to perform the operations of block 1804.

[0175] In block 1806, the apparatus receives during a second TTI after receiving during the first TTI. For example, the apparatus may receive a second TTI of a frame.

[0176] In some implementations, the circuit/module for receiving 1720 of Figure 17 performs the operations of block 1806. In some implementations, the code for receiving 1728 of Figure 17 is executed to perform the operations of block 1806.

[0177] In block 1808, the apparatus generates a channel estimate for decoding data from a second TTI based on a pilot from the first TTI. In some aspects, the pilot may be a demodulation reference signal (DMRS).

[0178] In some implementations, the circuit/module for generating a channel estimate 1722 of Figure 17 performs the operations of block 1808. In some implementations, the code for generating a channel estimate 1730 of Figure 17 is executed to perform the operations of block 1808.

[0179] Figure 19 illustrates a process 1900 for communicating in accordance with some aspects of the description. In some implementations, process 1900 may be performed in addition to (e.g., in conjunction with) process 1200 of Fig. 12. Process 1900 may occur within a processing circuit (e.g., processing circuit 1710 of Fig. 17), which may be located in an access terminal, a base station, or some other suitable device. In some implementations, process 1900 represents operations performed by processing circuit 624 of Figure 6. Obviously, in many respects within the scope of the description, process 1900 may be implemented by any suitable apparatus capable of supporting communication operations.

[0180] In block 1902, an apparatus (eg, a UE) receives an indication. For example, a UE may receive an indication transmitted by an eNB (for example, as discussed above in conjunction with block 1506 of Fig. 15 ). The indication is from a selected pilot structure based on a physical resource block (PRB) bundle, the PRB bundle including at least one PRB. In some aspects, the indication can be a precoding matrix (PMI) indicator. In some respects, the indication indicates a difference between neighboring resource block (RB) PMIs.

[0181] In some implementations, the circuit/module for receiving 1720 of Figure 17 performs the operations of block 1902. In some implementations, the code for receiving 1728 of Figure 17 is executed to perform the operations of block 1902.

[0182] In block 1904, the apparatus receives a pilot according to the indicated pilot structure (for example, from an eNB). In some aspects, the pilot may be a demodulation reference signal (DMRS).

[0183] In some implementations, the circuit/module for receiving 1720 of Figure 17 performs the operations of block 1904. In some implementations, the code for receiving 1728 of Figure 17 is executed to perform the operations of block 1904.

[0184] In block 1906, the apparatus generates a channel estimate. As discussed here, this operation can be based on the received pilot.

[0185] In some implementations, the circuit/module for generating a channel estimate 1722 of Figure 17 performs the operations of block 1906. In some implementations, the code for generating a channel estimate 1730 of Figure 17 is executed to perform operations block 1906.

[0186] Figure 20 illustrates a process 2000 for communication and according to some aspects of the description. In some implementations, process 2000 may be performed in addition to (e.g., in conjunction with) process 1200 of Fig. 12. Process 2000 may occur within a processing circuit (e.g., processing circuit 1710 of Fig. 17 ), which may be located in an access terminal, a base station, or some other suitable device. In some implementations, process 2000 represents operations performed by processing circuit 724 of Fig. 7. Obviously, in many respects within the scope of the description, process 2000 may be implemented by any suitable apparatus capable of supporting communication operations.

[0187] In block 2002, an apparatus (e.g., a UE) receives an indication of a traffic to pilot ratio (TPR) for demodulation reference signals (DMRSs). For example, a UE may receive an indication transmitted by an eNB (for example, as discussed above with respect to block 1604 of Fig. 16 ). In some respects, TPR is determined based on at least one of: a modulation and coding scheme (MCSD), a classification, or a rate.

[0188] In some implementations, the circuit/module for receiving 1720 of Figure 17 performs the operations of block 2002. In some implementations, the code for receiving 1728 of Figure 17 is executed to perform the operations of block 2002.

[0189] In block 2004, the device selects a transmission energy. As discussed here, this selection is based on the TPR obtained in block 2002.

[0190] In some implementations, the circuit/module for selecting a transmission energy 1724 of Figure 17 performs the operations of block 2004. In some implementations, the code for selecting a transmission energy 1732 of Figure 17 is executed to perform the operations of the 2004 block.

[0191] In block 2006, the device transmits signals according to the selected transmission energy. For example, the apparatus may transmit traffic at a selected transmit power level in block 2004.

[0192] In some implementations, the circuit/module for transmission 1726 of Figure 17 performs the operations of block 2006. In some implementations, the transmission code 1734 of Figure 17 is executed to perform the operations of block 2006.

[0193] Figure 21 is a schematic illustration of a wireless communication network 2100 including multiple communication entities as it may appear in some aspects of the description. As described herein, a programming entity or an entity being programmed can reside in, or be a part of, a base station, smartphone, small cell, or other entity. Child entities or braided nodes can reside in, or be part of, a smart alarm, a remote sensor, a smartphone, a telephone, a smart meter, a personal data assistant (PDA), a personal computer, a braiding node, and/or or a tablet computer. Obviously, the illustrated devices or components are merely illustrative, and any suitable node or device can appear within a wireless communication network within the scope of the present description.

Additional Aspects

[0194] One or more of the components, steps, features and/or functions illustrated in the figures may have a new arrangement and/or may be combined into a single component, step, feature or function or embodied in several components, steps or functions. Additional elements, components, steps and/or functions can also be added without departing from the novelty characteristics described here. Apparatus, devices and/or components illustrated in the figures may be configured to perform one or more of the methods, features or steps described herein. The novel algorithms described here can also be efficiently implemented in software and/or embedded in hardware.

[0195] It should be understood that the specific order or hierarchy of steps in the described methods is an illustration of the illustrative processes. Based on design preferences, it is understood that the specific order or hierarchy of steps in methods can be rearranged. The attached method claims the multi-step elements present in a sampling order, and should not be limited to the specific order or hierarchy presented unless specifically mentioned here. Additional elements, components, steps and/or functions can also be added or not used without departing from the description.

[0196] While features of the description may have been discussed with respect to particular implementations and figures, all implementations of the description may include one or more of the advantageous features discussed herein. In other words, while one or more implementations may have been discussed as having certain advantageous features, one or more of such features may also be used in accordance with any of the various implementations discussed here. Similarly, while the illustrative implementations may have been discussed here as device, system, or method implementations, it should be understood that such illustrative implementations may be implemented in various devices, systems, and methods.

[0197] Furthermore, it is noted that at least some implementations have been described as a process that is presented as a flowchart, a flowchart, a structure diagram, or a block diagram. Although a flowchart can describe operations as a sequential process, many of the operations can be performed in parallel or concurrently. Additionally, the order of operations may be re-arranged. A process is terminated when its operations are completed. In some respects, a process can correspond to a method, a function, a procedure, a subroutine, a subprogram, etc. When a process matches a function, its termination corresponds to a function return to the calling function or main function. One or more of the various methods described herein may be partially or wholly implemented by programming (e.g., instructions and/or data) which may be stored on a machine-readable, computer-readable, and/or processor-readable storage medium, and executed by one or more processors, machines and/or devices.

[0198] Those skilled in the art will further appreciate that the various illustrative logic blocks, modules, circuits, and algorithm steps described with respect to the implementations described herein may be implemented as hardware, software, firmware, middleware, microcode, or any combination thereof. To clearly illustrate this interchangeability, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the particular application and the design constraints imposed on the system as a whole.

[0199] Within the description, the term "illustrative" is used to mean "serving as an example, case or illustration". Any implementation or aspect described herein as "illustrative" is not necessarily to be considered as preferred or advantageous over other aspects of the description. Likewise, the term "aspects" does not require that every aspect of the description include the feature, advantage, or mode of operation discussed. The term "coupled" is used here to refer to direct or indirect coupling between two objects. For example, if object A physically touches object B, and object B touches object C, then objects A and C can still be considered coupled to each other - even if they don't directly physically touch each other. For example, a first matrix can be coupled to a second matrix in a package even though the first matrix is never directly physically in contact with the second matrix. The terms "circuit" and "circuitry" are used broadly, and are meant to include both hardware implementations of electrical devices and conductors which, when connected and configured, permit the performance of the functions described in the description, without limitation as to the type of electronic circuits, in addition to software implementations of information and instructions that, when executed by a processor, allow the performance of the functions described in the description.

[0200] As used herein, the term "determining" encompasses a wide variety of actions. For example, "determining" can include calculating, computing, processing, deriving, investigating, querying (eg, querying a table, a database, or other data structure), determining, and the like. Furthermore, "determining" can include receiving (eg, receiving information), accessing (eg, accessing data in a memory), and the like. Furthermore, "determining" can include resolving, selecting, choosing, establishing, and the like.

[0201] The foregoing description is provided to enable those skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects. Accordingly, the claims must not be limited to the aspects illustrated here, but the full scope consistent with the language of the claims must be agreed, where reference to an element in the singular must not mean "one and only one" unless specifically mentioned that way. form, but rather "one or more". Unless specifically noted otherwise, the term "some" refers to one or more. A phrase referring to "at least one of" or "at least one or more of" refers to one or more. A phrase referring to "at least one of" or "at least one or more of" or "one or more of" a list of items refers to any combination of those items, including singular elements. As an example, "at least one of: a, b or c" must cover: a; B; w; a and b; and a and c; b and c; a, b and c; 2a; 2b; 2c; 2a and b; a and 2b; 2a and 2b; and so on. All structural and functional equivalences to elements of the various aspects described throughout this description that are known or will later become known to those skilled in the art are expressly incorporated herein by reference and are to be encompassed by the claims. Furthermore, nothing described here should be dedicated to the public unless such description is explicitly mentioned in the claims. No claim element shall be considered under the provisions of 35 U.S.C. § 112, paragraph six, unless the element is expressly mentioned using the phrase "means to" or, in the case of a method claim, the element is mentioned using the phrase "step to".

[0202] Accordingly, the various features associated with the examples described here and illustrated in the attached drawings can be implemented in different examples and implementations without departing from the scope of the description. Therefore, although certain specific constructions and arrangements have been described and illustrated in the accompanying drawings, such implementations are merely illustrative and not restrictive of the scope of the description, as various other additions and modifications, and deletions with respect to the described implementations will be apparent to those versed in the technique. As such, the scope of the description is only determined by the literal language, and legal equivalences, of the claims that follow.

Claims (11)

1. Method for wireless communication, characterized in that it comprises: determining (902) a pilot structure where the pilot density differs over time within a transmission period; determining (1602) a traffic-to-pilot (TPR) ratio for a user equipment (UE) for demodulation reference signals (DMRSs), based on at least one ratio associated with the UE; transmitting (1604, 904) a TPR indication and a pilot frame indication to the user; identifying a physical resource block (PRB) bundle comprising at least one PRB; selecting another pilot structure based on the identified PRB bundle; and transmitting an indication of the other selected pilot structure. 2. Method according to claim 1, characterized in that it further comprises obtaining channel condition information for the UE and selecting the TPR for the UE based on the further channel condition. 3. Method according to claim 1, characterized in that it further comprises selecting a DMRS energy based on at least one of the MCS, classification or rate, and determining the TPR based on the DMRS energy. 4. Method, according to claim 1, characterized by the fact that the pilot density in an initial part of the transmission period is greater than the pilot density in a later part of the transmission period. 5. Method according to claim 1, characterized in that it further comprises, to select the other pilot structure, selecting spacing for pilots based on a bandwidth of the PRB bundle. 6. Computer-readable memory characterized by the fact that it has instructions stored therein that, when executed, cause the computer to perform the method as defined in any one of claims 1 to 5. 7. Apparatus for wireless communication characterized in that it comprises: means for determining (1326) a pilot frame where the pilot density differs over time within a transmission period; means for determining (1328) a traffic-to-pilot (TPR) ratio for a user equipment (UE) for demodulation reference signals (DMRSs), based on at least one ratio associated with the UE; means for transmitting (1314) a TPR indication and a pilot frame indication to the user; means for identifying a physical resource block (PRB) bundle comprising at least one PRB; means for selecting another pilot structure based on the identified PRB bundle; and means for transmitting an indication of the other selected pilot frame. 8. Apparatus according to claim 7, characterized in that it further comprises means for obtaining channel condition information for the UE and selecting the TPR for the UE based further on the channel condition. 9. Apparatus according to claim 7, characterized in that it further comprises means for selecting a DMRS energy based on at least one of the MCS, classification or rate, and determining the TPR based on the DMRS energy. 10. Apparatus according to claim 7, characterized in that the pilot density in an initial part of the transmission period is greater than the pilot density in a later part of the transmission period. 11. Apparatus according to claim 7, characterized in that it further comprises, for selecting the other pilot structure, means for selecting spacing for pilots based on a PRB bundle bandwidth.