Method and apparatus for wireless communication

Abstract

A method, system, and apparatus are described for a system that supports communication with a first group of devices using a first OFDM symbol duration associated with a first tone interval (i.e., a first physical layer (PHY) configuration) and wireless communication with a second group of devices using a PHY configuration associated with a second tone interval. A base station can transmit a set of discovery reference signals (DRS) in a narrowband region of the primary channel of a carrier. The DRS may have a first PHY configuration, and a secondary channel of the carrier may support communication using a second PHY configuration. The base station can use the first PHY configuration to transmit a first system information (SI) message for one group of devices, and it can use the second PHY configuration to transmit a second SI message for another group of devices.

Description

[0001] Cross-references

[0002] This patent application claims priority to U.S. Patent Application No. 15 / 250,586, filed August 29, 2016, entitled “Enhanced Component Carrier Discovery Reference Signals”, invented by Yoo et al.; and U.S. Provisional Patent Application No. 62 / 237,176, filed October 5, 2015, entitled “Enhanced Component Carrier Discovery Reference Signals”, invented by Yoo et al.; each of which has been assigned to the assignee of this application. Technical Field

[0003] In general, the following concerns wireless communications, and more specifically, enhanced component carrier discovery reference signals (DRS). Background Technology

[0004] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, and broadcasting. These systems can support communication with multiple users by sharing available system resources (e.g., time, frequency, and power). Examples of such multiple access systems include Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), and Orthogonal Frequency Division Multiple Access (OFDMA). A wireless multiple access communication system may include multiple base stations, each supporting communication from multiple communication devices simultaneously; these communication devices may also be referred to as User Equipment (UE).

[0005] In some cases, wireless systems can support communication using multiple physical (PHY) layer configurations. For example, different PHY layer configurations can use different symbol durations and different tone intervals. Different PHY layer configurations can be used to communicate with different groups of devices. Wireless systems that support different device types with different PHY layer configurations can use one or more DRSs to enable devices to identify, synchronize, and access the network. However, if the DRS is incompatible with different devices, some devices may experience access problems. Summary of the Invention

[0006] A base station can transmit a set of discovery reference signals (DRS) in the narrowband region of the primary channel of a carrier. The DRS can have a first physical layer (PHY) configuration based on a first orthogonal frequency division multiplexing (OFDM) symbol duration and tone spacing. The secondary channel of the carrier can support communication using a second PHY configuration based on a second OFDM symbol duration and tone spacing. In some cases, the base station can use the first PHY configuration to transmit a first system information (SI) message and then use the second PHY configuration to transmit a second SI message to support different device groups. Different system information can be transmitted at different times or on different channels (e.g., system information with a second PHY configuration can be transmitted on a secondary channel).

[0007] A method for wireless communication in a system is described, the system supporting communication with a first group of devices using a first Orthogonal Frequency Division Multiplexing (OFDM) symbol duration associated with a first tone interval and communication with a second group of devices using a second OFDM symbol duration associated with a second tone interval. The method may include: identifying one or more DRSs in a narrowband region of a carrier, wherein the one or more DRSs use the first OFDM symbol duration and the first tone interval; identifying a second region of the carrier, wherein the second region supports the second OFDM symbol duration and the second tone interval; and communicating in the second region of the carrier using the second OFDM symbol duration and the second tone interval.

[0008] An apparatus for wireless communication in a system is described, the system supporting communication with a first group of devices using a first Orthogonal Frequency Division Multiplexing (OFDM) symbol duration associated with a first tone interval and communication with a second group of devices using a second OFDM symbol duration associated with a second tone interval. The apparatus may include: a unit for identifying one or more DRSs in a narrowband region of a carrier, wherein the one or more DRSs use the first OFDM symbol duration and the first tone interval; a unit for identifying a second region of the carrier, wherein the second region supports the second OFDM symbol duration and the second tone interval; and a unit for communication in the second region of the carrier using the second OFDM symbol duration and the second tone interval.

[0009] Another apparatus for wireless communication in a system is described, the system supporting communication with a first group of devices using a first Orthogonal Frequency Division Multiplexing (OFDM) symbol duration associated with a first tone interval and communication with a second group of devices using a second OFDM symbol duration associated with a second tone interval. The apparatus may include: a processor; a memory electrically communicatively connected to the processor; and instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to: identify one or more DRSs in a narrowband region of a carrier, wherein the one or more DRSs use the first OFDM symbol duration and the first tone interval; identify a second region of the carrier, wherein the second region supports the second OFDM symbol duration and the second tone interval; and communicate in the second region of the carrier using the second OFDM symbol duration and the second tone interval.

[0010] A non-transitory computer-readable medium is described, storing code for wireless communication in a system that supports communication with a first group of devices using a first orthogonal frequency division multiplexing (OFDM) symbol duration associated with a first tone interval and communication with a second group of devices using a second OFDM symbol duration associated with a second tone interval. The code may include instructions executable to: identify one or more DRSs in a narrowband region of a carrier, wherein the one or more DRSs use the first OFDM symbol duration and the first tone interval; identify a second region of the carrier, wherein the second region supports the second OFDM symbol duration and the second tone interval; and communicate in the second region of the carrier using the second OFDM symbol duration and the second tone interval.

[0011] In some examples of the methods, apparatus, or non-transitory computer-readable media described herein, one or more DRSs in a narrowband region of a carrier are identified using a first receiver operating according to a first OFDM symbol duration and a first tone interval, and wherein communication in a second region of the carrier is performed using a second receiver operating according to a second OFDM symbol duration and a second tone interval. Additionally or alternatively, some examples may include procedures, features, units, or instructions for performing a cell search or measurement process using the first receiver, wherein one or more DRSs are identified at least in part based on the cell search or measurement process.

[0012] Examples of the methods, apparatus, or non-transitory computer-readable media described herein may also include: procedures, features, units, or instructions for transmitting one or more DRS and first system information messages during a first time period using a first OFDM symbol duration and a first tone interval; and for transmitting a second system information (SI) message during a second time period using a second OFDM symbol duration and a second tone interval. Additionally or alternatively, in some examples, the second SI message includes differences relative to the first SI message.

[0013] In some examples of the methods, apparatus, or non-transitory computer-readable media described herein, one or more DRS, first SI messages, and second SI messages are transmitted on a first channel supporting communication with a first group of devices and a second group of devices. The method further includes transmitting one or more additional DRS in a second channel using a first OFDM symbol duration and a first tone interval, wherein the second channel supports communication with the second group of devices. Additionally or alternatively, some examples may include procedures, features, units, or instructions for performing the following operations: transmitting one or more DRS and first SI messages in a first channel of a carrier during a first time period, wherein the first channel supports communication with the first group of devices and the second group of devices; and transmitting one or more additional DRS and second SI messages in both the first and second channels of a carrier during a second time period, wherein the second channel supports communication with the second group of devices.

[0014] Some examples of the methods, apparatus, or non-transitory computer-readable media described herein may also include processes, features, units, or instructions for performing the following operations: receiving a measurement report from the UE, and determining, at least in part based on the measurement report, the number of system bandwidth channels used by a neighboring base station, determining that the neighboring base station supports communication using a second OFDM symbol duration and a second tone interval, or determining that the neighboring base station does not support a second OFDM symbol duration and a second tone interval. Additionally or alternatively, some examples may include processes, features, units, or instructions for performing the following operations: receiving a measurement report from the UE, and determining, at least in part based on the measurement report, the number of system bandwidth channels used by the neighboring base station.

[0015] In some examples of the methods, apparatus, or non-transitory computer-readable media described herein, the measurement report includes information for each channel, including DRS used by neighboring base stations. Additionally or alternatively, some examples may include procedures, features, units, or instructions for performing the following operations: determining that multiple CCA attempts on the primary channel are unsuccessful during a transmission window, and avoiding sending one or more DRSs during the transmission window.

[0016] Some examples of the methods, apparatus, or non-transitory computer-readable media described herein may also include processes, features, units, or instructions for performing the following operations: determining that a first CCA attempt on a primary channel of the carrier is unsuccessful; determining that a second CCA attempt on a non-primary channel of the carrier is successful; and transmitting one or more DRSs on a non-primary channel, at least in part based on determining that the first CCA attempt is unsuccessful and that the second CCA attempt is successful, wherein the non-primary channel comprises a narrowband region of the carrier. Additionally or alternatively, in some examples, one or more DRSs include an indication of whether communication using a first OFDM symbol duration and a first tone interval is supported by a channel comprising a narrowband region.

[0017] Some examples of the methods, apparatus, or non-transitory computer-readable media described herein may also include processes, features, units, or instructions for performing the following operations: determining whether a channel supports communication using a first OFDM symbol duration and a first tone interval based at least in part on: one or more DRSs, SI messages, phase shifts between different pilots within one or more DRSs, the relative position of a secondary synchronization signal (SSS) within a DRS relative to a primary synchronization signal (PSS), or a successful decoding attempt of an SI message. Additionally or alternatively, some examples may include processes, features, units, or instructions for performing the following operations: identifying a first transmission power level for one or more DRSs, wherein the first transmission power level is independent of the bandwidth occupied by a transmission containing one or more DRSs; identifying the bandwidth of a carrier; and adjusting a second transmission power level for an area outside the bandwidth occupied by a transmission containing one or more DRSs based at least in part on: the first transmission power level for one or more DRSs, the total transmission power for a carrier, or the bandwidth occupied by a transmission containing one or more DRSs, or a combination thereof.

[0018] In some examples of the methods, apparatus, or non-transitory computer-readable media described herein, one or more DRSs include: PSS, SSS, Master Information Block (MIB), Cell-Specific Reference Signal (CRS), Channel State Information Reference Signal (CSI-RS), or any combination thereof. Additionally or alternatively, in some examples, one or more DRSs are directed to a first group of devices and a second group of devices.

[0019] In some examples of the methods, apparatuses, or non-transitory computer-readable media described herein, the narrowband region of the carrier includes six or eight center resource blocks of the carrier's channel. Additionally or alternatively, in some examples, the duration of the first OFDM symbol is greater than the duration of the second OFDM symbol, and the first tone interval is less than the second tone interval.

[0020] In some examples of the methods, apparatuses, or non-transitory computer-readable media described herein, when a narrowband region is frequency-division multiplexed with a second region of a carrier, the narrowband region is defined by a first guard band and a second guard band. Attached Figure Description

[0021] Figure 1 An example of a wireless communication system supporting enhanced component carrier (eCC) discovery reference signal (DRS) according to aspects of this disclosure is shown;

[0022] Figure 2 An example of a wireless communication system supporting eCC DRS according to aspects of this disclosure is shown;

[0023] Figure 3A , 3B The 3C and 3C examples illustrate DRS configurations that support eCC DRS according to aspects of this disclosure;

[0024] Figure 4 An example of a process flow in a system supporting eCC DRS according to aspects of this disclosure is shown;

[0025] Figure 5 and Figure 6 A block diagram of a wireless device supporting eCC DRS according to aspects of this disclosure is shown;

[0026] Figure 7 A diagram of an eCC DRS module according to an aspect of this disclosure is shown;

[0027] Figure 8 A diagram of a wireless communication system including a device supporting eCC DRS, according to aspects of this disclosure, is shown.

[0028] Figure 9 A diagram of a system including an eCC DRS-enabled device is shown, according to aspects of this disclosure; and

[0029] Figures 10 to 13 A flowchart illustrating a method for eCC DRS is shown according to an aspect of this disclosure. Detailed Implementation

[0030] Some wireless communication systems can use enhanced component carrier (eCC) to improve throughput, latency, or reliability. In systems supporting eCC operation, user equipment (UE) can rely on discovery reference signals (DRS) to discover cells deployed in the network. Various DRS configurations supporting multichannel coexistence between eCC and non-eCC communication and supporting different physical (PHY) layer configurations for operation with different devices are described.

[0031] For example, in some cases, eCC can be introduced by combining non-eCC systems, and both eCC and non-eCC systems can be served on the same channel (e.g., a channel in an unlicensed band at 5 GHz). Examples of non-eCC systems can include: Long Term Evolution (LTE), Advanced LTE (LTE-A), Licensed Assisted Access (LAA), or LTE in unlicensed spectrum. Examples of eCC systems can include 5G New Radio (NR) systems. Hybrid networks can include non-eCC base stations and mobile devices. eCC base stations can also support non-eCC communications to serve non-eCC devices.

[0032] eCC can be characterized by short symbol duration, wide tone interval, short subframe duration, operation in a contention-based spectrum, or wide bandwidth. DRS can be used for initial acquisition, neighbor cell acquisition, and measurements of serving and neighboring cells. DRS may include synchronization and / or reference signals, system information signals, and reference signals.

[0033] In some cases, eCC-enabled base stations can simultaneously support both non-eCC and eCC communication. Therefore, eCC base stations can transmit both non-eCC DRS and eCC DRS to accommodate various types of UEs. Compared to non-eCC carriers, which can have relatively small bandwidths (e.g., 20MHz), eCC carriers can have relatively wide system bandwidths (e.g., 80MHz). Furthermore, an eCC carrier can include one or more channels (e.g., bandwidth segments, such as 20MHz). Non-eCC UEs can be served within an eCC carrier. In some cases, non-eCC UEs can be served on a subset of channels within an eCC carrier. We refer to the channels where non-eCC UEs can be served as primary channels and the channels where non-eCC UEs are not served as secondary channels as secondary channels. Since the wideband eCC carrier spans both primary and secondary channels, eCC UEs are served on both primary and secondary channels. As a result, non-eCC DRS can be transmitted on the primary channel. One or more primary channels may also exist.

[0034] For both eCC-compatible and non-eCC-compatible communication, there are several different options for DRS, including transmitting a shared DRS only on the main channel, transmitting a separate DRS on all channels, and transmitting a shared DRS on all channels.

[0035] In some cases, the UE or network can distinguish between base stations that support non-eCC and those that support eCC. Information regarding the availability of eCC services can be carried, for example, in the main information block (MIB) or enhanced MIB (eMIB) within a system information block (SIB) such as SIB1 or enhanced SIB1 (eSIB1), or can be conveyed through other means within the DRS. Furthermore, the base station can obtain measurement results of neighboring cells by requesting the UE to perform DRS measurements of neighboring cells. In some cases, the measurement results may not disclose the neighboring cell type (e.g., eCC or non-eCC) or the bandwidth associated with that cell to the UE. However, the base station can interpret the measurement information obtained by the UE and implicitly determine the cell type.

[0036] In some examples, power scaling of the transmission can be employed to maintain a constant power spectral density (PSD) for DRS transmission (e.g., for accurate measurement and to avoid interruptions in ongoing data transmission). For example, a base station can use a fixed PSD on the central six resource blocks (RBs), regardless of the transmission bandwidth.

[0037] The aspects of this disclosure described above are further described below in the context of wireless communication systems. Several different examples of DRS configurations are also described. The aspects of this disclosure are further illustrated by apparatus diagrams, system diagrams, and flowcharts relating to eCC DRS, and are further described with reference to apparatus diagrams, system diagrams, and flowcharts relating to eCC DRS.

[0038] Figure 1 An example of a wireless communication system 100 supporting eCC DRS according to various aspects of this disclosure is shown. The wireless communication system 100 includes a base station 105, a UE 115, and a core network 130. In some examples, the wireless communication system 100 may be an LTE / LTE-A network. The wireless system 100 may use combined DRS configurations to support multi-channel coexistence between eCC and non-eCC communications.

[0039] Base station 105 can wirelessly communicate with UE 115 via one or more base station antennas. Each base station 105 can provide communication coverage for its respective geographic coverage area 110. The communication link 125 shown in the wireless communication system 100 can include uplink (UL) transmission from UE 115 to base station 105 or downlink (DL) transmission from base station 105 to UE 115. UE 115 can be distributed throughout the wireless communication system 100, and each UE 115 can be stationary or mobile. UE 115 can also be referred to as a mobile station, subscriber station, remote unit, wireless device, access terminal (AT), handheld device, user agent, client, or similar terms. UE 115 can also be a cellular phone, wireless modem, handheld device, personal computer, tablet computer, personal electronic device, machine-type communication (MTC) device, etc. Some UE 115 may support communication using eCC, while eCC communication may not be supported by some UE 115. System 100 can therefore support communication with multiple groups of devices that can operate according to different PHY layer configurations.

[0040] Base station 105 can communicate with core network 130 and with each other. For example, base station 105 can interface with core network 130 via backhaul link 132 (e.g., S1, etc.). Base station 105 can communicate with each other directly or indirectly (e.g., via core network 130) on backhaul link 134 (e.g., X2, etc.). Base station 105 can perform radio configuration and scheduling for communication with UE 115, or can operate under the control of a base station controller (not shown). In some examples, base station 105 can be a macro cell, small cell, hotspot, etc. Base station 105 can also be referred to as evolved Node B (eNB) 105.

[0041] In some cases, UE 115 or base station 105 may operate in shared or unlicensed spectrum. These devices may perform Free Channel Assessment (CCA) or enhanced CCA (eCCA) before communication to determine channel availability. CCA may include energy detection procedures to determine the presence of any other active transmissions. For example, the device may infer that a change in the received signal strength indicator (RSSI) of the power meter indicates channel occupancy. Specifically, a signal power concentrated in a specific bandwidth and exceeding a predetermined noise floor may indicate the presence of another wireless transmitter. CCA may also include the detection of a specific sequence indicating channel usage. For example, another device may transmit a specific preamble before transmitting a data sequence.

[0042] In some cases, the wireless communication system 100 may use one or more eCCs. As described above, an eCC may be characterized by one or more of the following features: short symbol duration, wide tone spacing, short subframe duration, and wide bandwidth. In some cases, an eCC may be associated with a carrier aggregation (CA) configuration or a dual connectivity configuration (e.g., when multiple serving cells have suboptimal backhaul links). An eCC may also be configured for use in unlicensed spectrum or shared spectrum (e.g., where more than one operator is licensed to use the spectrum). Various portions of the bandwidth used by the system 100 may support eCC operation.

[0043] eCC, characterized by its wide bandwidth, can include one or more channel segments. For example, the eCC carrier bandwidth can be 80MHz, and it can include four 20MHz channel segments. CCA / eCCA can be performed separately on each 20MHz channel, and transmissions performed by eCC devices (e.g., base stations and UEs) are subject to the success of CCA / eCCA. Therefore, if CCA / eCCA fails on some channel segments, the actual transmission bandwidth for a given transmission instance may be less than the eCC carrier bandwidth. Some base stations 105 can support communication using eCC, while eCC may not be supported by some base stations 105 and the system.

[0044] eCC can use short symbol durations or TTI lengths. Shorter symbol durations can be associated with increased subcarrier spacing. eCC can use dynamic time-division duplex (TDD) operation (i.e., it can switch from DL to UL operation for short bursts based on dynamic conditions). Examples of communications using eCC can include 5G NR deployed in licensed, unlicensed, or shared spectrum, or using sub-6 GHz radio frequency (RF) bands or millimeter-wave (mmW) RF bands.

[0045] UE 115, attempting to access a wireless network, can perform an initial cell search by detecting the Primary Synchronization Signal (PSS) from base station 105. The PSS enables time slot timing synchronization and indicates the PHY layer identification value. UE 115 can then receive the Secondary Synchronization Signal (SSS). The SSS enables radio frame synchronization and provides a Cell Identifier (CID) value, which can be combined with the PHY layer identification value to identify the cell. The SSS also enables detection of duplex mode and cyclic prefix (CP) length. Some systems (e.g., TDD systems) may transmit the SSS instead of the PSS. The PSS and SSS can be located in the center 62 and 72 subcarriers, respectively. After receiving the PSS and SSS, UE 115 can receive the MIB, which can be transmitted on the Physical Broadcast Channel (PBCH). The MIB may contain system bandwidth information, the System Frame Number (SFN), and the Physical Hybrid Automatic Repeat Request Indicator Channel (PHICH) configuration.

[0046] After decoding the MIB, UE 115 can receive one or more SIBs. For example, SIB1 may contain cell access parameters and scheduling information for other SIBs. Decoding SIB1 enables UE 115 to receive SIB2. SIB2 may contain Radio Resource Control (RRC) configuration information related to the Random Access Channel (RACH) procedure, paging, Physical Uplink Control Channel (PUCCH), Physical Uplink Shared Channel (PUSCH), power control, Sounding Reference Signal (SRS), and cell prohibition. After initial cell synchronization is completed, UE 115 can decode the MIB, SIB1, and SIB2 before accessing the network. The MIB can be transmitted on the PBCH and can use the first four OFDMA symbols of the second time slot of the first subframe of each radio frame. It can use the middle six RBs (i.e., 72 subcarriers) in the frequency domain.

[0047] The MIB carries information for initial UE access, including, for example, the DL channel bandwidth with respect to the RB, PHICH configuration (e.g., duration and resource allocation), and SFN. A new MIB can be broadcast every fourth radio frame (i.e., SFN mod 4 = 0) and replayed every frame (e.g., every 10 ms). Each repetition is scrambled with a different scrambling code. After reading the MIB (e.g., a new version or copy), the UE 115 can then try different phases of the scrambling code until it achieves a successful Cyclic Redundancy Check (CRC). The phase of the scrambling code (e.g., 0, 1, 2, or 3) allows the UE 115 to identify which of the four repetitions has been received. Therefore, the UE 115 can determine the current SFN by reading the decoded SFN in the transmission and adding the scrambling code phase.

[0048] After receiving the MIB, UE 115 can receive one or more SIBs. Different SIBs can be defined depending on the type of system information being conveyed. A new SIB1 can be transmitted in the fifth subframe of every eighth frame (i.e., SFN mod8 = 0) and replayed every other frame (e.g., every 20 ms). SIB1 can include access information, which may include cell identification information, and it can also indicate whether UE 115 is allowed to camp on base station 105. SIB1 can also include cell selection information or may include cell selection parameters. In addition, SIB1 can include scheduling information for other SIBs. SIB2 can be dynamically scheduled based on the information in SIB1 and can include access information and parameters related to common and shared channels. The periodicity of SIB2 can be set to 8, 16, 32, 64, 128, 256, or 512 radio frames. In some cases (e.g., in systems supporting eCC operation), the combination of synchronization signals, system information signals, and reference signals can be collectively referred to as DRS. eCC DRS can use some aspects of the corresponding non-eCC signals, but the aspects based on eCC operation can also be different.

[0049] Therefore, base station 105 can transmit DRS in the narrowband region of the primary channel of the carrier. DRS can have a first PHY configuration based on a first Orthogonal Frequency Division Multiplexing (OFDM) symbol duration and tone interval. The secondary channel of the carrier can support communication using a second PHY configuration based on a second OFDM symbol duration and tone interval. The primary channel of the carrier outside of DRS transmission can support communication using either a first or second PHY configuration based on either the first or second OFDM symbol duration and tone interval. In some cases, base station 105 can use the first PHY configuration to transmit a first System Information (SI) message and then use the second PHY configuration to transmit a second SI message to support different groups of UEs 115. Different system information messages can be transmitted at different times or on different channels (e.g., system information with a second PHY configuration can be transmitted on a secondary channel).

[0050] Figure 2 An example of a wireless communication system 200 for eCC DRS according to aspects of this disclosure is shown. The wireless communication system 200 may include a base station 105-a and a UE 115-a, which may be a reference... Figure 1 Examples of corresponding devices are described. Wireless communication system 200 can use eCC to improve throughput, latency, and reliability. UE 115-a can rely on DRS to discover cells such as base station 105-a. Wireless communication system 200 can support multi-channel coexistence between eCC and non-eCC communication using a combined DRS configuration.

[0051] In some examples, eCC is characterized by short symbol duration (e.g., 16.67 μs compared to 66.7 μs), wide tone spacing (e.g., 75 kHz compared to 15 kHz), short subframe duration (e.g., 200 μs), operation in contention-based spectrum, or wide bandwidth (e.g., 80 MHz, 100 MHz, etc.). For example, eCC using contention-based or unlicensed RF bands can employ a Listen-After-Speak (LBT) process. Therefore, due to efficient PHY layer / Media Access Control (MAC) design, eCC-based communication can also allow for design features that enable low-cost implementations compared to other communication systems (e.g., an 80 MHz deployment compared to multiple 20 MHz non-eCC carriers).

[0052] In some cases, eCC can be used as an evolution of shared access systems, such as standalone deployment on unlicensed spectrum, or in LAA systems using secondary carriers (e.g., SCells) in the unlicensed spectrum and primary carriers in the licensed spectrum within a CA configuration. eCC communication can also occur on licensed frequency bands (e.g., radio spectrum bands licensed for specific purposes) and can be associated with licensed shared access, such as adaptive vertical sharing between the incumbent Priority Access Licensee (PAL) and General Licensed Access (GAA).

[0053] DRS can be used for initial acquisition, neighbor cell acquisition, and measurements of serving and neighboring cells. DRS can include synchronization and / or reference signals (e.g., PSS, SSS, Cell-Specific Reference Signal (CRS), etc.), system information signals, and reference signals (e.g., CRS, Channel State Information Reference Signal (CSI-RS), etc.). DRS can be transmitted quasi-periodically, and a DRS Measurement Timing Configuration (DMTC) window can be defined periodically (e.g., every 80 ms). In some cases, DRS can be transmitted within a DMTC window upon successful CCA, and multiple DRS transmission opportunities can exist within a single DMTC window. In some cases, DRS can be transmitted by a base station 105 that cannot communicate using eCC (i.e., a non-eCC base station 105).

[0054] In some cases, eCC synchronization signals such as PSS and SSS can be carried on the central six RBs (e.g., 1.08 MHz), allowing cell search with narrowband waveforms and at lower sampling rates (i.e., compared to the non-eCC sampling rate and eCC sampling rate used for data transmission on 20 MHz). In some cases, the synchronization signal may be scattered across the channel. In some cases, synchronization signal sequences can be transmitted via interleaved tones, and new eCC synchronization signal sequences can be defined. Although in some instances, this may introduce search complexity due to fine time resolution. In other examples, synchronization signal sequences can be transmitted in the center of a frequency band with mathematical numbers associated with eCC (e.g., eCC symbol duration, frequency gap, etc.). For example, with a 75 kHz eCC subcarrier spacing and transmitted on 72 tones, the synchronization signal can occupy approximately 5 MHz. In some examples, waveforms containing synchronization signals can be transmitted using non-eCC mathematical numbers (e.g., a 15 kHz subcarrier spacing, where PSS / SSS occupies the central 1 MHz). Alternatively, a new sequence can be sent to UE 115-a to determine the timing, and once UE 115-a knows the timing, the synchronization signal can be used.

[0055] For example, base station 105-a can support both non-eCC and eCC communication. Therefore, base station 105-a can transmit both non-eCC DRS and eCC DRS to accommodate various types of UE 115. Compared to a non-eCC carrier, which may have a relatively small bandwidth (e.g., a single 20MHz band), eCC can have a relatively wide system bandwidth (e.g., 80MHz that may include multiple 20MHz channels). An eCC carrier may include one or more channels (e.g., four 20MHz channels). In some cases, a non-eCC UE 115 may be served on a primary channel (e.g., a primary 20MHz channel), and as a result, non-eCC DRS may be transmitted only on the primary channel. One or more primary channels may exist to serve UE 115.

[0056] For example, when transmitting waveforms containing synchronization signals using non-eCC features, the central N resource blocks (e.g., where N=6) can contain synchronization signals such as PSS / SSS. The central N resource blocks can also contain eMIBs conveying system information, CRS, and CSI-RS. DRS transmitted outside the central N RBs can contain eSIB1s to convey additional system information, as well as associated reference signals and control channel information.

[0057] In some cases, hybrid mathematical numbering can be used for eCC DRS. DRS in the center band can use non-eCC mathematical numbering (e.g., 15kHz tone interval), while areas outside the DRS within the channel can use eCC mathematical numbering (e.g., 75kHz tone interval). In some cases, guard bands can be used to reduce inter-carrier interference. Additionally, UE 115-a can have two parallel hardware branches, such as a main data branch for processing received symbols in the 75kHz tone interval (i.e., for processing received eCC data) and a narrowband or cell searcher branch for receiving DRS in the center band in the 15kHz tone interval.

[0058] For both transmission-compatible eCC and non-eCC communication, there are several different options for DRS, including: transmitting a shared DRS only on the primary channel (e.g., as...). Figure 3A As shown), send separate DRS on all channels (e.g., as shown). Figure 3B As shown), and transmit a shared DRS on all channels (e.g., as shown). Figure 3C (As shown).

[0059] When a shared DRS is transmitted on the main channel, a separate eCC DRS transmission may not be necessary. However, in some cases, an eCC SIB1 containing different information or indicating a difference relative to the previous SIB1 may be transmitted. The eCC SIB1 may use a 75kHz tone interval. As a result, a non-eCC UE 115 may only recognize the non-eCC DRS portion. In some cases, the non-eCC DRS and eCC SIB1 may be transmitted as a new combined DRS. Alternatively, the DRS may contain only the non-eCC DRS, and the eCC SIB1 may be transmitted in a separate time / frequency configuration.

[0060] In some examples of the initial acquisition process of DRS being transmitted on the main channel, and as referenced below. Figure 3A Further described, the cell searcher branch can detect synchronization signals, and UE 115-a can detect SIB1. eCC acquisition can then be performed, where the main hardware branch can read eCC SIB1 on the main channel and determine the bandwidth. As a result, the main data branch can open up the system bandwidth.

[0061] Alternatively, the cell searcher branch can search for synchronization signals, and the main data branch can read eCC SIB1 on the main channel and determine the bandwidth. The main data branch can then open up the system bandwidth. In some cases, UE 115-a may not know during initial acquisition whether base station 105-a supports non-eCC or eCC. To address this, information about eCC service can be carried in the eMIB, SIB1, or conveyed through other means within the DRS or through successful decoding of eCC SIB1.

[0062] When base station 105-a requests measurement results from neighboring cells, UE 115-a can perform DRS measurements on the neighboring cells. In some cases, the measurement results may not inform UE 115-a of the neighboring cell type (e.g., eCC or non-eCC) or the bandwidth associated with that cell. However, base station 105-a can use the obtained information through other means (e.g., X2 interface between eNBs, measurement result history, etc.) and interpret the measurement information obtained by UE 115-a accordingly, implicitly determining the cell type. In some cases, base station 105-a may request UE 115-a to perform readings of neighboring eMIBs and / or SIB1s and report the returned neighboring cell information.

[0063] In some examples, base station 105-a may fail all CCA attempts on the primary channel, and as a result, base station 105-a may not send a DRS within a given DMTC window. Alternatively, a DRS can be sent on a non-primary channel where CCA attempts have been successful. If a DRS is sent on a non-primary channel, further ambiguity may exist between different types of UE 115 regarding which channel to use. In other words, some UE 115 may determine that a non-primary channel carries non-eCC service or that the non-primary channel is an eCC channel. To resolve this potential ambiguity, base station 105-a can communicate in the eMIB or SIB1 that a non-eCC service does not exist on the channel, and that the channel is a non-primary channel with an eCC carrier.

[0064] When the DRS transmission is separate and spans all channels, the DRS can exist on all channels, where the separate eCC DRS uses non-eCC mathematical numbering on the center 6 RBs. Some examples of the initial acquisition process where the DRS transmission is separate and spans all channels are provided below, as referenced. Figure 3B Further described, the cell searcher branch can search for synchronization signals on any channel, and the main data branch can read eCC SIB1 on the channel and determine the bandwidth. The main data branch can then open up the system bandwidth.

[0065] If DRS transmissions are segmented and span all channels, there may be ambiguity regarding which UE 115 is supported. For example, on the primary channel, there may be ambiguity regarding non-eCC UE 115 that can detect valid eCC PSS / SSS, but locating SIB1 may be problematic. Several steps may be needed to resolve this. For example, base station 105-a could convey information in the eMIB to indicate the presence of non-eCC service. Similarly, on non-primary channels, steps can be taken to avoid ambiguity regarding UE 115 that detects valid PSS / SSS. Therefore, information may again be conveyed in the eMIB to indicate that no available non-eCC service exists.

[0066] In some examples, a determination can be made regarding the eCC support capability of base station 105. For example, information about the availability of eCC service can be carried in the eMIB, SIB1, or otherwise conveyed within the DRS. For example, different phase shift values ​​can be used to carry the information between two antenna ports (e.g., between the CRS and CSI-RS ports). Alternatively, successful decoding of eCCSIB1 can indicate eCC service. Additionally, for base station 105-a to obtain neighboring cell measurement results, UE 115-a can know the type of neighboring cells and report the cell measurement results in the frequency band (e.g., 20MHz).

[0067] In other cases, and as referenced below Figure 3C To further explain, shared DRS transmissions across all channels are possible. In other words, shared eCC DRS can be transmitted using non-eCC mathematical notations on the central 6 RBs. It may be appropriate for UE 115-a to use the central 6 RBs to determine the primary frequency band from the non-primary band. In some cases, the relative positions of the synchronization signals with each other (e.g., different positions of SSS relative to SSS) can be used, including the relative positions of the synchronization signals within the DRS. Alternatively, information about the primary or non-primary frequency band can be included in the eMIB, or different phase shift values ​​can be used for the primary and non-primary frequency bands between the two antenna ports.

[0068] In some cases, if UE 115-a detects base station 105-a on a non-primary channel, base station 105-a can communicate in the eMIB or SIB1 that there is no non-eCC service on the channel and that the channel is a non-primary channel of an eCC carrier. Furthermore, UE 115-a can determine that the channel is part of eCC communication and search for neighboring channels using known timings to establish it as the primary channel.

[0069] In some examples, UE 115-a can determine during initial acquisition whether base station 105-a supports non-eCC or eCC. This information can be conveyed in the eCC service indication carried in the eMIB, SIB1, or along with another DRS indication. For example, different phase shifts can be used on the CSI-RS to signal eCC capability. Alternatively, if UE 115-a first detects a non-primary channel, it can determine that base station 105-a supports eCC, and if UE 115-a first detects a primary channel, it can attempt to detect adjacent non-primary channels (e.g., assuming no 20MHz eCC system bandwidth). For neighboring cell measurements when transmitting a shared DRS across all channels, UE 115-a can report measurements every 20MHz because it knows the type of neighboring cells.

[0070] In some examples, power scaling of the transmission can be adapted to maintain a constant PSD for DRS transmission (e.g., for accurate measurements and to avoid interruptions in ongoing data transmission). In some cases, base station 105-a can use a fixed PSD on the central six RBs, regardless of the transmission bandwidth. For example, in a 20MHz transmission with 23dBm transmission power, base station 105-a can use 10dBm / MHz for the central six RBs. In the case of an 80MHz transmission with 23dBm transmission power, although the flattened PSD could be converted to 4dBm / MHz, power can be boosted in the central six RBs, and 10dBm / MHz can still be used. As a result, the power on other RBs may have to be reduced (e.g., depressurized) to meet the overall 23dBm transmission power.

[0071] Figure 3A An example of a DRS configuration 301 supporting eCC DRS according to aspects of this disclosure is shown. In some cases, DRS configuration 301 may represent as described in reference... Figure 1-2 The description covers aspects of the technology performed by UE115 or base station 105. DRS configuration 301 can represent an example where shared DRS is used only for the primary channel. The primary channel can support both eCC and non-eCC communication, and the secondary channel can support only eCC UEs.

[0072] In some cases, a carrier supporting eCC may include multiple frequency bands. For example, an 80MHz eCC carrier may include four 20MHz channels, such as channel 305-a. When operating in contention-based spectrum, the base station may perform an LBT procedure (e.g., CCA) before communicating on each channel. In some cases, multiple DRS attempts may exist after an LBT procedure within a DMTC window 330-a. The base station may avoid sending a DRS after an unsuccessful CCA 310-a. However, a successful CCA 315-a after a subsequent LBT procedure on the same channel 305-a may enable the DRS to be sent. DRS period 320-a may include combined DRS transmissions (e.g., DRS supporting both eCC and non-eCC UE 115). For example, DRS areas 335-a, SIB1 340-a, and eCC SIB1 345-a may all be transmitted within DRS period 320-a.

[0073] In some cases, when a shared DRS transmission is carried on the primary channel, a separate eCC DRS transmission may not be necessary. For example, DRS period 320-a may include non-eCC SIB1 340-a in a portion of the spectrum bordering DRS area 335-a. DRS area 335-a may include DRS such as synchronization signals PSS and SSS. eCC SIB1 345-a may follow a DRS and may be a standalone SI message or may indicate any change or difference relative to the previous SIB1 340-a. In some cases, a non-eCC UE 115 may not recognize eCC SIB1 345-a, but may only recognize the non-eCC DRS portion of DRS period 320-a, such as 335-a and SIB1 340-a.

[0074] As described above, in some examples where shared DRS is transmitted on the main channel, for example, the cell searcher branch of UE 115 operating at a 15kHz tone interval and in narrowband can detect the synchronization signal. UE 115 can then use the main hardware branch operating at a 15kHz tone interval to detect SIB1 340-a. Afterwards, the main data branch can switch to a 75kHz tone interval, and eCC capture can occur. The main hardware branch operating at a 75kHz tone interval can read eCC SIB1 345-a on the main channel (e.g., one of channels 305-a) and determine the bandwidth. As a result, the main data branch can be opened to the system bandwidth. In an alternative example of system capture with shared DRS on the main channel, the cell searcher branch operating at a 15kHz tone interval and in narrowband can search for the synchronization signal in DRS area 335-a, and the main data branch operating at a 75kHz tone interval can read eCC SIB1 345-a and determine the bandwidth. As a result, the main data branch can be opened to the system bandwidth. In some cases, the eCC UE 115 may not know during initial acquisition whether base station 105 supports non-eCC or eCC. To address this, information about eCC services can be carried in the eMIB, SIB1, or conveyed through other means within DRS period 320-a or through successful decoding of eCC SIB1 345-a.

[0075] Figure 3B An example of a DRS configuration 302 supporting eCC DRS according to aspects of this disclosure is shown. In some cases, DRS configuration 302 may represent as described in reference... Figure 1-2 The description covers aspects of the technology performed by UE115 or base station 105. DRS configuration 302 can represent an example where a separate DRS is used on all channels. The primary channel can support both eCC and non-eCC communication, and the secondary channel can support only eCC UEs.

[0076] In some cases, multiple DRS attempts may occur within a DMTC window 330-b covering all channels (e.g., channel 305-b) of the eCC carrier. In some cases, an unsuccessful CCA 310-b may prevent the transmission of a DRS. However, after a subsequent LBT process on channel 305-b, a successful CCA 315-b may allow the DRS to be transmitted on the corresponding channel. In one case, the DRS period 320-b and / or the eCC DRS period 325-b may occur after a successful CCA 315-b.

[0077] DRS period 320-b may include non-eCC SIB1 340-b in the portion of the spectrum bordering DRS region 335-b (e.g., the central 6 RBs), where DRS region 335-b can be used for DRS transmission. In some cases, eCC DRS period 325-b may also include DRS region 335-c bordered by eCC SIB1 345-b. In some examples, eCC DRS period 325-b may also include a guard band 350 between DRS region 335-c and eCC SIB1 345-b.

[0078] In an example where DRS transmissions for eCC and non-eCC are separated and the initial acquisition process spans all channels, the UE 115's cell searcher branch can search for synchronization signals on any channel, and the main data branch can read the eCC SIB1345-b and determine the bandwidth on the channel where eCC DRS transmissions exist. The main data branch can then open up the system bandwidth.

[0079] Figure 3C An example of a DRS configuration 303 supporting eCC DRS according to aspects of this disclosure is shown. In some cases, DRS configuration 303 may represent as described in reference... Figure 1-2 The description covers aspects of the technology performed by UE115 or base station 105. DRS configuration 303 can represent an example where shared DRS is used on all channels. The primary channel can support both eCC and non-eCC communication, and the secondary channel can support only eCC UEs.

[0080] In DRS configuration 303, multiple DRS attempts can exist within a single DMTC window 330-c during transmission across all channels (e.g., channel 305-c). In some cases, an unsuccessful CCA 310-c may prevent the transmission of a DRS on each channel. However, a successful CCA 315-c during a subsequent LBT process on channel 305-c may allow the DRS to be transmitted on the appropriate channel. A DRS period 320-c or an eCC DRS period 325-c may follow a successful CCA 315-c. In some examples, a DRS period 320-c or a separate eCC DRS period 325-c may exist on each channel.

[0081] In some examples, DRS period 320-c may include: DRS region 335-d, and SIB1 340-c occupying the spectrum bordering DRS region 335-d, and subsequent eCC SIB1 345-c. eCC DRS period 325-c may include DRS region 335-e bounded by data 355. In some examples, eCC DRS period 325-c may also include guard band 360 between DRS region 335-e and data region 355.

[0082] Figure 4 An example of process flow 400 in a system supporting eCC DRS according to various aspects of this disclosure is shown. Process flow 400 may include base station 105-b and UE 115-b, which may be a reference Figure 1-2 Examples of the corresponding devices described. Process flow 400 may represent a technique for DRS transmission in a system supporting a first group of devices capable of communicating with a first OFDM symbol duration and tone interval, and a second group of devices supporting communication with a second OFDM symbol duration and tone interval.

[0083] In some cases, the second set of devices may also be capable of communicating using the first OFDM symbol duration and tone interval. In some cases, process flow 400 may be based on a carrier with multiple channels. Some channels, which may be referred to as primary channels, may support communication between base station 105-b and the two sets of devices. Other channels, which may be referred to as non-primary channels or secondary channels, may support communication with the second set of devices.

[0084] At step 405, base station 105-b may perform CCA to clear the channel used for communication. In some cases, base station 105-b may determine that multiple CCA attempts on the primary channel are unsuccessful during the transmission window and avoid transmitting DRS during the transmission window. In some cases, base station 105-b may: determine that at least one first CCA attempt on the primary channel of the carrier is unsuccessful, determine that a second CCA attempt on a non-primary channel of the carrier is successful, and transmit one or more DRSs on the non-primary channel based on determining that at least one first CCA attempt is unsuccessful and determining that the second CCA attempt is successful. The non-primary channel may include a narrowband region of the carrier.

[0085] In some cases, UE 115-b can monitor the channel for one or more signals (e.g., DRS) transmitted by base station 105-b. For example, base station 105-b can determine the location of one or more DRSs (e.g., a narrowband area of ​​the carrier) and map the DRSs to a set of resources (e.g., resources within a first OFDM symbol duration, resources with a first tone interval, etc.). Then, at step 410, base station 105-b can transmit one or more DRSs to UE 105-b. UE 115-b can accordingly identify the presence of one or more DRSs based on the monitoring and can receive the DRSs transmitted from base station 105-a at step 410. Thus, UE 115-b and base station 105-b can identify DRSs in a narrowband area of ​​the carrier, and the DRSs can use a first OFDM symbol duration and a first tone interval. In some examples, DRSs include PSS, SSS, MIB, CRS, CSI-RS, other signals or transmissions, or combinations thereof.

[0086] In some examples, base station 105-b can determine the duration of communication with UE 115-b, such as a second region of a carrier. Base station 105-b can then identify and allocate resources within the second region of the carrier for communication. In this case, UE 115-b can monitor and identify the communication resources allocated within the second region of the carrier for which communication takes place. Accordingly, base station 105-b and UE 115-b can identify a second region of the carrier, which may support a second OFDM symbol duration and a second tone interval.

[0087] In some cases, a first receiver (e.g., a cell searcher branch) operating according to the first OFDM symbol duration and a first tone interval is used to identify DRS in a narrowband area of ​​the carrier. Communication in a second area of ​​the carrier can be performed using a second receiver (e.g., a main hardware branch) operating according to the second OFDM symbol duration and a second tone interval. In some cases, UE 115-b can use the first receiver to perform cell search or measurement procedures; DRS can be identified based on the cell search or measurement procedures.

[0088] In some cases, at step 415, base station 105-b can transmit and UE 115-b can receive non-eCC SIB1. For example, base station 105-b can transmit DRS and first SI messages during a first time period using a first OFDM symbol duration and a first tone interval. In some cases, the second SI message includes differences relative to the first SI message.

[0089] At step 420, base station 105-b can transmit and UE 115-b can receive eCCSIB1. In other words, base station 105-b can transmit a second SI message during a second time period using the second OFDM symbol duration and the second tone interval. In some cases, base station 105-b can transmit DRS and first SI messages in a first channel of the carrier during a first time period, the first channel supporting communication with both the first and second groups of devices; and can transmit additional DRS and second SI messages in either the first or second channel of the carrier, or both the first and second channels, during a second time period, the second channel supporting communication with the second group of devices. In some cases, additional DRS and SI messages can also be transmitted in the first channel. In some cases, the first channel can be the main channel of the carrier. In other words, the first channel can support both the first and second groups of devices.

[0090] At step 425, base station 105-b and UE 115-b can transmit and receive data using eCC. For example, base station 105-b and UE 115-b can communicate in a second region of the carrier using the second OFDM symbol duration and the second tone interval. In some cases, base station 105-b can receive a measurement report from UE 115-b and determine, based on the measurement report, whether the neighboring base station 105 supports communication using the second OFDM symbol duration and the second tone interval, or whether the neighboring base station does not support the second OFDM symbol duration and the second tone interval. In some cases, the measurement report includes information for each channel having a DRS used by the neighboring base station 105.

[0091] In some cases, base station 105-b can also determine the number of channels in the system bandwidth used by neighboring base stations based on measurement reports. For example, base station 105-b can determine that the system bandwidth of a neighboring base station comprises a single channel or multiple channels. In some cases, measurements are performed on each channel containing the DRS (e.g., on each 20MHz channel of the carrier), and the measurement report may include information for each channel including the DRS used by the neighboring base station.

[0092] Figure 5 A block diagram of a wireless device 500 supporting eCC DRS according to various aspects of this disclosure is shown. The wireless device 500 may be a reference. Figure 1 and Figure 2 Examples of aspects of the described UE 115 or base station 105. Wireless device 500 may include a receiver 505, an eCCDRS module 510, and a transmitter 515. Wireless device 500 may also include a processor. Each of these components can communicate with each other.

[0093] Receiver 505 can receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to eCC DRS). This information can be transmitted to other components of the device. Receiver 505 can serve as a reference. Figure 8 The transceiver 825 described or referenced Figure 9 Examples of aspects of the transceiver 925 described.

[0094] The eCC DRS module 510 can identify DRS (e.g., one or more DRSs) in a narrowband region of a carrier. In some cases, a second region (e.g., a region where eCC data is transmitted) is identified by the UE detecting eCC transmissions. The DRS can use a first OFDM symbol duration and a first tone interval, and the second region can support a second OFDM symbol duration and a second tone interval. For example, the eCC DRS module 510, combined with a receiver or transmitter, can communicate in a second region of the carrier using a second OFDM symbol duration and a second tone interval. The eCC DRS module 510 can also be a reference Figure 8 The eCC DRS module 805 described or referenced Figure 9 Examples of aspects of the described eCC DRS module 905.

[0095] Transmitter 515 can transmit signals received from other components of wireless device 500. In some examples, transmitter 515 can be co-located with receiver in transceiver module. For example, transmitter 515 can be a reference... Figure 8 The transceiver 825 described or referenced Figure 9 Examples of aspects of the transceiver 925 described. Transmitter 515 may include a single antenna, or it may include multiple antennas.

[0096] Figure 6 A block diagram of a wireless device 600 supporting eCC DRS according to various aspects of this disclosure is shown. The wireless device 600 may be a reference. Figure 1 , Figure 2 and Figure 5 Examples of aspects of the described wireless device 500, UE 115, or base station 105. Wireless device 600 may include a receiver 605, an eCCDRS module 610, and a transmitter 630. Wireless device 600 may also include a processor. Each of these components can communicate with each other.

[0097] Receiver 605 can receive information, which can be transmitted to other components of the device. Receiver 605 can also perform reference operations. Figure 5 The receiver 505 is described in terms of its function. Receiver 605 may be referenced. Figure 8The transceiver 825 described or referenced Figure 9 Examples of aspects of the transceiver 925 described herein. Receiver 605 may also include or represent multiple receiver branches, such as cell searcher branch 607 and main data branch 609. Cell searcher branch 607 may operate at a first tone interval (e.g., a 15 kHz tone interval over narrowband) (i.e., monitoring and operation using the first tone interval), and main data branch 609 may operate at a second tone interval (e.g., a 75 kHz tone interval over wideband) (i.e., monitoring and operation using the second tone interval), as described herein.

[0098] eCC DRS module 610 can be used as a reference. Figure 5 Examples of aspects of the described eCC DRS module 510. The eCC DRS module 610 may include a DRS identification component 615 and an eCC area communication component 625. The eCC DRS module 610 may be a reference... Figure 8 The eCC DRS module 805 described or referenced Figure 9 Examples of aspects of the described eCC DRS module 905.

[0099] DRS identification component 615 can identify DRS in a narrowband region of a carrier. DRS can use a first OFDM symbol duration and a first tone interval. In some cases, DRS includes PSS, SSS, MIB, CRS, CSI-RS, or a combination of these signals. In some cases, DRS is directed to a first group of devices and a second group of devices. The narrowband region of the carrier can include, for example, six or eight center RBs of the carrier's channel. In some cases, when the narrowband region is frequency-division multiplexed with a second region, the narrowband region is defined by a first guard band and a second guard band.

[0100] In some cases, the second region can support a second OFDM symbol duration and a second tone interval. In some cases, the first OFDM symbol duration is greater than the second OFDM symbol duration, and the first tone interval is less than the second tone interval. In some cases, a first receiver operating according to the first OFDM symbol duration and the first tone interval can be used to identify the DRS in the narrowband region of the carrier, and communication in the second region of the carrier can be performed using a second receiver operating according to the second OFDM symbol duration and the second tone interval. The eCC region communication component 625 can communicate in the second region of the carrier using the second OFDM symbol duration and the second tone interval.

[0101] Transmitter 630 can transmit signals received from other components of wireless device 600. In some examples, transmitter 630 can be co-located with receiver in transceiver module. For example, transmitter 630 can be a reference... Figure 8 The transceiver 825 described or referenced Figure 9 Examples of aspects of the transceiver 925 described. The transmitter 630 may use a single antenna, or it may use multiple antennas.

[0102] Figure 7 A block diagram of an eCC DRS module 700 according to an aspect of this disclosure is shown, which may be an example of a corresponding component of wireless device 500 or wireless device 600, which may represent an aspect of UE 115 or base station 105. In other words, the eCC DRS module 700 may be a reference... Figure 5 and Figure 6 Examples of aspects of the described eCC DRS module 510 or eCC DRS module 610. eCC DRS module 700 may also be a reference. Figure 8 The eCC DRS module 805 described or referenced Figure 9 Examples of aspects of the described eCC DRS module 905.

[0103] The eCC DRS module 700 may include: a DRS identification component 705, an eCC area identification component 710, an eCC area communication component 715, a cell search component 720, a DRS component 725, a system information component 730, a measurement reporting component 735, a neighbor support determination component 740, a CCA component 745, a primary channel determination component 750, a transmission power level component 755, and a bandwidth identification component 760. Each of these modules may communicate directly or indirectly with each other (e.g., via one or more buses). In some cases, the eCC DRS module 700 may include some of the components described, but others may be excluded.

[0104] DRS identification component 705 can identify a DRS in a narrowband area of ​​a carrier, the DRS using a first OFDM symbol duration and a first tone interval. As described above, DRS identification component 705 can be part of a cell seeker branch of a radio device. In some cases, DRS includes PSS, SSS, MIB, CRS, CSI-RS, etc. In some cases, DRS is directed to a first group of devices and a second group of devices.

[0105] In some cases, the second OFDM symbol duration and the second tone interval are specified. As described above, the eCC area identification component 710 can be part of the main data branch of a wireless device. In some cases, the first OFDM symbol duration is greater than the second OFDM symbol duration, and the first tone interval is less than the second tone interval. In some cases, a first receiver operating according to the first OFDM symbol duration and the first tone interval is used to identify DRS in a narrowband area of ​​the carrier. Communication in a second area of ​​the carrier can be performed using a second receiver operating according to the second OFDM symbol duration and the second tone interval. The eCC area communication component 715 can communicate in a second area of ​​the carrier using the second OFDM symbol duration and the second tone interval. The cell search component 720 can perform a cell search or measurement procedure using the first receiver and can identify DRS based on the cell search or measurement procedure.

[0106] DRS component 725 can be combined with other components or modules of a wireless communication device (e.g., reference...). Figure 5 and Figure 6 The transmitter 515 or 630 described herein performs various operations. The DRS component 725 can transmit DRS and a first SI message in a first channel of the carrier during a first time period, and transmit additional DRS and second SI messages in the first channel or the second channel of the carrier, or both, during a second time period. The first channel can support communication with both first and second groups of devices, and the second channel can support communication with the second group of devices. The DRS component 725 can transmit DRS on a non-primary channel based, for example, determining that a first CCA attempt failed and that a second CCA attempt succeeded. The non-primary channel may include a narrowband region of the carrier. The DRS component 725 can also transmit DRS in a non-primary channel of the carrier. In some cases, the DRS component 725 can use a first OFDM symbol duration and a first tone interval to transmit DRS and the first SI message during the first time period.

[0107] In some cases, depending on the various operations of the wireless device (e.g., UE 115 or base station 105), a DRS, a first SI message, and a second SI message are transmitted on a first channel that supports communication with the first group of devices and the second group of devices. In some cases, the DRS includes an indication of whether the channel, which includes a narrowband area, supports communication using a first OFDM symbol duration and a first tone interval.

[0108] System information component 730 can, in conjunction with transmitter 515 or 630, transmit a second SI message during a second time period using a second OFDM symbol duration and a second tone interval. In some cases, the second SI message includes differences relative to the first SI message. Measurement reporting component 735 can, in conjunction with a reference... Figure 6 The receiver 605 described receives measurement reports from user equipment.

[0109] The neighbor support determination component 740 can determine, based on a measurement report, the number of system bandwidth channels used by the neighboring base station, whether the neighboring base station supports communication using the second OFDM symbol duration and the second tone interval, or whether the second OFDM symbol duration and the second tone interval are not supported by the neighboring base station. In some examples, the neighbor support determination component 740 can determine the number of channels using the system bandwidth by the neighboring base station based on a received measurement report. The measurement report may include information for each channel that includes a DRS used by the neighboring base station.

[0110] CCA component 745 can: determine that multiple CCA attempts on the primary channel fail during the transmission window, thus avoiding the transmission of DRS during the transmission window; determine that the first CCA attempt on the primary channel of the carrier fails; and determine that the second CCA attempt on a non-primary channel of the carrier succeeds.

[0111] The main channel determination component 750 can determine whether the channel supports communication using the first OFDM symbol duration and the first tone interval based on the DRS, SI message, phase shift between DRS, or successful decoding attempt of the SI message.

[0112] The transmission power level component 755 can identify: a first transmission power level for one or more DRSs, and a second transmission power level for the carrier adjusted based on the first transmission power level for the one or more DRSs, the total transmission power for the carrier, and the bandwidth of the carrier. For example, the first transmission power level can be independent of the bandwidth used to transmit the DRS. The bandwidth identification component 760 can identify the bandwidth used for the carrier.

[0113] Figure 8 A diagram is shown of a wireless communication system 800 including devices supporting eCC DRS according to various aspects of this disclosure. For example, the wireless communication system 800 may include a UE 115-c, which may be as described in reference... Figure 1 , Figure 2 and Figures 5 to 7 Examples of wireless devices 500, 600, or UE 115 described.

[0114] UE 115-c may also include an eCC DRS module 805, a processor 810, a memory 815, a transceiver 825, an antenna 830, and an eCC module 835. Each of these modules can communicate directly or indirectly with each other (e.g., via one or more buses). The eCC DRS module 805 may be as described in the reference. Figures 5 to 7 An example of the eCC DRS module described.

[0115] Processor 810 may include intelligent hardware devices (e.g., central processing unit (CPU), microcontroller, application-specific integrated circuit (ASIC), etc.). Memory 815 may include random access memory (RAM) and read-only memory (ROM). Memory 815 may store computer-readable, computer-executable software including instructions that, when executed, cause the processor and thus the UE115-c to perform the various functions described herein (e.g., eCC DRS, etc.). In some cases, software 820 may not be directly executable by the processor, but may enable the computer (e.g., when compiled and executed) to perform the functions described herein.

[0116] As described above, transceiver 825 can communicate bidirectionally with one or more networks via one or more antennas, wired or wireless links. For example, transceiver 825 can communicate bidirectionally with a base station or UE. Transceiver 825 may also include a modem to modulate packets and provide the modulated packets to the antenna for transmission and demodulate packets received from the antenna. In some cases, the wireless device may include a single antenna 830. However, in some cases, the device may have more than one antenna 830, which may be capable of transmitting or receiving multiple wireless transmissions simultaneously. As described herein, transceiver 825 may include parallel branches (e.g., a cell search branch and a main data branch).

[0117] The eCC module 835 can use eCC to enable operations such as communication using shared or unlicensed spectrum, using reduced TTI or subframe duration, or using a large number of component carriers (CC).

[0118] Figure 9 A diagram of a wireless system 900 including devices supporting eCC DRS is shown according to various aspects of this disclosure. For example, the wireless system 900 may include base stations 105-e and 105-f, which may be as described in reference... Figure 1 , Figure 2 and Figures 5 to 7 Examples of described wireless devices 500, 600, or base station 105. Base stations 105-e and 105-f may also include components for bidirectional voice and data communication, including components for transmitting communication and components for receiving communication. For example, base stations 105-e and 105-f may communicate bidirectionally with one or more UEs (UE115-d, 115-e).

[0119] Base stations 105-e and 105-f may further include an eCC DRS module 905, a processor 910, a memory 915, a transceiver 925, an antenna 930, a base station communication module 935, and a network communication module 940. Each of these modules can communicate directly or indirectly with each other (e.g., via one or more buses). The eCC DRS module 905 may be as described in the reference. Figures 5 to 7 An example of the eCC DRS module described.

[0120] Processor 910 may include intelligent hardware devices (e.g., CPU, microcontroller, ASIC, etc.). Memory 915 may include RAM and ROM. Memory 915 may store computer-readable, computer-executable software including instructions that, when executed, cause the processor and thus the base stations 105-e and 105-f to perform the various functions described herein (e.g., eCC DRS, etc.). In some cases, software 920 may not be directly executable by the processor, but may enable a computer (e.g., when compiled and executed) to perform the functions described herein.

[0121] As described above, transceiver 925 can communicate bidirectionally with one or more networks via one or more antennas, wired or wireless links. For example, transceiver 925 can communicate bidirectionally with a base station or UE. Transceiver 925 may also include a modem to modulate packets and provide the modulated packets to the antenna for transmission, and demodulate packets received from the antenna. In some cases, the wireless device may include a single antenna 930. However, in some cases, the device may have more than one antenna 930, which may be capable of transmitting or receiving multiple wireless transmissions simultaneously.

[0122] The base station communication module 935 can manage communication with other base stations and may include a controller or scheduler for controlling communication of UEs cooperating with other base stations. For example, the base station communication module 935 can coordinate the scheduling of transmissions to the UE for various interference mitigation techniques (e.g., beamforming or joint transmission). In some examples, the base station communication module 935 may provide an X2 interface within LTE / LTE-A wireless communication network technology to facilitate communication between base stations 105.

[0123] The network communication module 940 can manage communication with the core network 130-A (e.g., via one or more wired backhaul links). For example, the network communication module 940 can manage the transmission of data communication for client devices (e.g., one or more UEs).

[0124] Figure 10A flowchart illustrating a method 1000 for eCC DRS is shown according to various aspects of this disclosure. The operation of method 1000 can be performed by, as referenced... Figure 1 and Figure 2 The UE 115 or base station 105 or its components are described. For example, the operation of method 1000 may be performed by an eCC DRS module as described herein. In some examples, the UE 115 or base station 105 may execute a set of codes for controlling the functional elements of the device to perform the functions described below. Alternatively or additionally, the UE 115 or base station 105 may use dedicated hardware to perform aspects of the functions described below.

[0125] At box 1005, UE 115 or base station 105 can identify one or more DRSs in a narrowband region of the carrier, wherein the one or more DRSs use the above reference. Figures 2 to 4 The description includes the duration of the first OFDM symbol and the first tone interval. In some examples, the operation of box 1005 can be determined by reference, etc. Figure 7 The described DRS identification component is executed.

[0126] At box 1010, UE 115 or base station 105 can identify a second region of the carrier, wherein the second region supports the above reference. Figures 2 to 4 The description refers to the duration of the second OFDM symbol and the second tone interval. In some examples, the operation of box 1010 can be determined by, as in the reference... Figure 6 The eCC DRS module described is executed.

[0127] At box 1015, UE 115 or base station 105 can use the above reference. Figures 2 to 4 The second OFDM symbol duration and the second tone interval are described for communication. This communication can take place, for example, in a second region of the carrier. In some examples, the operation of box 1015 can be determined by, as in reference... Figure 7 The eCC area communication component described is executed.

[0128] Figure 11 A flowchart of a method 1100 for eCC DRS according to various aspects of this disclosure is shown. The operation of method 1100 can be performed by, as referenced... Figure 1 and Figure 2 The UE 115 or base station 105 or its components are described. For example, the operation of method 1100 may be performed by an eCC DRS module as described herein. In some examples, the UE 115 or base station 105 may execute a set of codes for controlling the functional elements of the device to perform the functions described below. Alternatively or additionally, the UE 115 or base station 105 may use dedicated hardware to perform aspects of the functions described below.

[0129] At box 1105, UE 115 or base station 105 can identify one or more DRSs in a narrowband region of the carrier, wherein the one or more DRSs use the reference above. Figures 2 to 4 The first OFDM symbol duration and the first tone interval are described. In some examples, the operation of box 1105 can be determined by, as in reference... Figure 7 The described DRS identification component is executed.

[0130] At box 1110, UE 115 or base station 105 can identify a second region of the carrier, wherein the second region supports the above reference. Figures 2 to 4 The description refers to the duration of the second OFDM symbol and the second tone interval. In some examples, the operation of box 1110 can be determined by, as in the reference... Figure 6 The eCC DRS module described is executed.

[0131] At box 1115, UE 115 or base station 105 can use the above reference. Figures 2 to 4 The first OFDM symbol duration and the first tone interval described herein are used to transmit one or more DRS and first SI messages during the first time period. In some examples, the operation of box 1115 can be performed by, as referenced Figure 7 The DRS component described is executed.

[0132] At box 1120, UE 115 or base station 105 can use the above reference. Figures 2 to 4 The second OFDM symbol duration and the second tone interval, as described, are used to send the second SI message during the second time period. In some examples, the operation of box 1120 can be determined by, as referenced... Figure 7 The system information components described are executed.

[0133] At box 1125, UE 115 or base station 105 can use the above reference. Figures 2 to 4 The second OFDM symbol duration and the second tone interval described herein communicate in a second region of the carrier. In some examples, the operation of box 1125 can be determined by reference to [reference needed]. Figure 7 The eCC area communication component described is executed.

[0134] Figure 12 A flowchart illustrating a method 1200 for eCC DRS is shown according to various aspects of this disclosure. The operation of method 1200 can be performed by, as referenced... Figure 1 and Figure 2The UE 115 or base station 105 or its components are described. For example, the operation of method 1200 can be performed by an eCC DRS module as described herein. In some examples, the UE 115 or base station 105 can execute a set of codes for controlling the functional elements of the device to perform the functions described below. Alternatively or additionally, the UE 115 or base station 105 can use dedicated hardware to perform aspects of the functions described below.

[0135] At box 1205, UE 115 or base station 105 can identify one or more DRSs in the narrowband region of the carrier, wherein the one or more DRSs use the above reference. Figures 2 to 4 The first OFDM symbol duration and the first tone interval are described. In some examples, the operation of box 1205 can be determined by, as in the reference... Figure 7 The described DRS identification component is executed.

[0136] At box 1210, UE 115 or base station 105 can identify a second region of the carrier, wherein the second region supports the above reference. Figures 2 to 4 The description refers to the duration of the second OFDM symbol and the second tone interval. In some examples, the operation of box 1210 can be determined by, as in the reference... Figure 6 The eCC DRS module described is executed.

[0137] At box 1215, UE 115 or base station 105 can use the above reference. Figures 2 to 4 The first OFDM symbol duration and first tone interval described herein are used to transmit one or more DRS and first SI messages during a first time period. In some examples, the operation of box 1215 can be determined by reference to [reference needed]. Figure 7 The description refers to the discovery of reference signal components for execution.

[0138] At box 1220, UE 115 or base station 105 can use the above reference. Figures 2 to 4 The second OFDM symbol duration and the second tone interval described herein are used to transmit the second SI message during the second time period. In some cases, one or more DRS, the first SI message, and the second SI message are transmitted on a first channel that supports communication with the first group of devices and the second group of devices. In some examples, the operation of block 1220 may be as described in reference Figure 7 The system information components described are executed.

[0139] At box 1225, UE 115 or base station 105 may transmit one or more additional DRSs in a second channel using a first OFDM symbol duration and a first tone interval, wherein the second channel supports [the above reference]. Figures 2 to 4 The second group of devices described communicates. In some examples, the operation of box 1225 can be performed by, as referenced... Figure 7 The DRS component described is executed.

[0140] At box 1230, UE 115 or base station 105 can use the above reference. Figures 2 to 4 The second OFDM symbol duration and the second tone interval described herein communicate in a second region of the carrier. In some examples, the operation of box 1230 can be determined by reference to [reference needed]. Figure 7 The eCC area communication component described is executed.

[0141] Figure 13 A flowchart illustrating method 1300 for eCC DRS is shown according to various aspects of this disclosure. The operation of method 1300 can be performed by, as referenced... Figure 1 and Figure 2 The UE 115, base station 105, or components thereof are described. For example, the operation of method 1300 may be performed by an eCC DRS module as described herein. In some examples, the UE 115 or base station 105 may execute a set of codes for controlling the functional elements of the device to perform the functions described below. Alternatively or additionally, the UE 115 or base station 105 may use dedicated hardware to perform aspects of the functions described below.

[0142] At box 1305, UE 115 or base station 105 can identify one or more DRSs in a narrowband region of the carrier, wherein the one or more DRSs use the reference above. Figures 2 to 4 The first OFDM symbol duration and the first tone interval are described. In some examples, the operation of box 1305 can be determined by, as in reference... Figure 7 The described discovery reference signal recognition component is executed.

[0143] At box 1310, UE 115 or base station 105 can identify a second region of the carrier, wherein the second region supports the above reference. Figures 2 to 4 The description refers to the duration of the second OFDM symbol and the second tone interval. In some examples, the operation of box 1310 can be determined by, as in reference... Figure 6 The eCC DRS module described is executed.

[0144] At box 1315, UE 115 or base station 105 may transmit one or more DRS and first SI messages in a first channel of a carrier during a first time period, wherein the first channel supports [the above reference]. Figures 2 to 4 The first group of devices and the second group of devices described communicate with each other. In some examples, the operation of box 1315 can be performed by, as referenced... Figure 7 The DRS component described is executed.

[0145] At box 1320, UE 115 or base station 105 may transmit one or more additional DRS and second SI messages in the first and second channels of the carrier during the second time period, wherein the second channel supports [the above reference]. Figures 2 to 4 The second group of devices described communicates. In some examples, the operation of box 1320 can be performed by, as in reference... Figure 7 The DRS component described is executed.

[0146] At box 1325, UE 115 or base station 105 can use the above reference. Figures 2 to 4 The second OFDM symbol duration and the second tone interval described herein communicate in a second region of the carrier. In some examples, the operation of box 1325 may be as described in reference [reference]. Figure 7 The eCC area communication component described is executed.

[0147] It should be noted that these methods describe possible implementations, and the operations and steps can be rearranged or otherwise modified to make other implementations possible. In some examples, aspects of two or more methods from methods 1000, 1100, 1200, or 1300, which are referenced... Figure 10 , 11 The methods 1000, 1100, 1200, and 1300 are described in 1, 12, or 13. It should be noted that methods 1000, 1100, 1200, and 1300 are merely exemplary embodiments, and the operation of methods 1000, 1100, 1200, and 1300 can be arranged or otherwise modified to make other embodiments possible. For example, aspects of each of methods 1000, 1100, 1200, or 1300 may include steps or aspects of other methods, or other steps or techniques described herein. Therefore, aspects of this disclosure can provide eCC DRS.

[0148] The description herein is provided to enable those skilled in the art to implement or use the present disclosure. Various modifications to the present disclosure will be apparent to those skilled in the art, and the general principles defined herein can be applied to other variations without departing from the scope of the disclosure. Therefore, the present disclosure is not limited to the examples and designs described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0149] As used herein, the phrase “based on” should not be interpreted as a reference to a closed set of conditions. For example, an exemplary step described as “based on condition A” may be based on both condition A and condition B without departing from the scope of this disclosure. In other words, as used herein, the phrase “based on” should be interpreted in the same manner as the phrase “at least partially based on”.

[0150] The functions described herein can be implemented using hardware, software executed by a processor, firmware, or any combination thereof. If implemented using software executed by a processor, the functions can be stored on or transmitted on a computer-readable medium as one or more instructions or code. Other examples and implementations are within the scope of this disclosure and the appended claims. For example, due to the nature of software, the above-described functions can be implemented using software executed by a processor, hardware, firmware, hardwired, or any combination of these. Features implementing the functions can also be physically located in various locations, including being distributed such that portions of the functions are implemented in different physical locations. As used herein (including in the claims), the term “and / or” when used in a list of two or more items means that any one of the listed items can be used alone, or any combination of two or more of the listed items can be used. For example, if a combination is described as containing components A, B, and / or C, then the combination can contain only A; contain only B; contain only C; contain a combination of A and B; contain a combination of A and C; contain a combination of B and C; or contain a combination of A, B, and C. Additionally, as used herein (including in the claims), the word “or” used in a list of items (e.g., a list of items described by phrases such as “…at least one” or “one or more…”) indicates an inclusive list, such that a list such as “at least one of A, B or C” means A or B or C or AB or AC or BC or ABC (i.e., A and B and C).

[0151] Computer-readable media includes both non-transitory computer storage media and communication media, wherein the communication media includes any medium that facilitates the transfer of a computer program from one place to another. Non-transitory storage media can be any available medium accessible by a general-purpose or special-purpose computer. By way of example, and not limitation, non-transitory computer-readable media can include RAM, ROM, electrically erasable programmable read-only memory (EEPROM), compressed optical disc (CD) ROM or other optical disc storage devices, magnetic disk storage devices, or other magnetic storage devices, or any other non-transitory medium that can be used to carry or store desired units of program code having instructions or data structures and that can be accessed by a general-purpose or special-purpose computer or a general-purpose or special-purpose processor. Furthermore, any connection is appropriately referred to as computer-readable media. For example, if software is transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, these are all included in the definition of media. As used in this article, disks and optical discs include CDs, laser discs, optical discs, digital multifunction discs (DVDs), floppy disks, and Blu-ray discs. Disks typically copy data magnetically, while optical discs copy data optically using lasers. Combinations of these are also included within the scope of computer-readable media.

[0152] The techniques described in this article can be used in various wireless communication systems, such as CDMA, TDMA, FDMA, OFDMA, Single-Carrier Frequency Division Multiple Access (SC-FDMA), and others. The terms "system" and "network" are often used interchangeably. CDMA systems can implement wireless technologies such as CDMA2000 and Universal Terrestrial Radio Access (UTRA). CDMA2000 covers the IS-2000, IS-95, and IS-856 standards. IS-2000 versions 0 and A are commonly referred to as CDMA2000 1X, 1X, etc. IS-856 (TIA-856) is commonly referred to as CDMA2000 1xEV-DO, High-Speed ​​Packet Data (HRPD), etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. TDMA systems can implement wireless technologies such as Global System for Mobile Communications (GSM). OFDMA systems can implement wireless technologies such as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, and Flash-OFDM. UTRA and E-UTRA are part of the Universal Mobile Telecommunications System (UMTS). 3GPP LTE and Advanced LTE (LTE-A) are newer versions of UMTS using E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, and GSM are described in documents from an organization called the 3rd Generation Partnership Project (3GPP). CDMA2000 and UMB are described in documents from an organization called the 3rd Generation Partnership Project 2 (3GPP2). The technologies described herein can be used in the aforementioned systems and wireless technologies, as well as in other systems and wireless technologies. However, the description herein is for illustrative purposes regarding LTE systems, and LTE terminology is used extensively in the above descriptions; however, these technologies can be applied beyond LTE applications.

[0153] In LTE / LTE-A networks (including those described herein), the term Evolved Node B (eNB) can be used broadly to describe a base station. The wireless communication systems or systems described herein may include heterogeneous LTE / LTE-A networks in which different types of eNBs provide coverage for various geographic areas. For example, each eNB or base station may provide communication coverage for macro cells, small cells, or other types of cells. The term "cell" is a 3GPP term and, depending on the context, can be used to describe a base station, a carrier or component carrier (CC) associated with a base station, or the coverage area of ​​a carrier or base station (e.g., a sector, etc.).

[0154] A base station may include, or may be referred to by those skilled in the art, as a base station transceiver, wireless base station, access point (AP), wireless transceiver, node B, eNB, home node B, home eNB, or some other suitable term. The geographical coverage area of ​​a base station may be divided into sectors that constitute only a portion of the coverage area. The wireless communication system or system described herein may include different types of base stations (e.g., macro or small cell base stations). The UE described herein may be capable of communicating with various types of base stations and network devices, including macro eNBs, small cell eNBs, relay base stations, etc. Overlapping geographical coverage areas may exist for different technologies.

[0155] Macro cells typically cover a relatively large geographic area (e.g., a radius of several kilometers) and allow unrestricted access for UEs with service subscriptions to network providers. Compared to macro cells, small cells are lower-power base stations that can operate in the same or different (e.g., licensed, unlicensed, etc.) frequency bands as macro cells. Depending on the examples, small cells can include pico cells, femto cells, and microcells. For example, a pico cell can cover a small geographic area and allow unrestricted access for UEs with service subscriptions to network providers. A femto cell can also cover a small geographic area (e.g., a home) and can provide restricted access for UEs associated with the femto cell (e.g., UEs in a Closed Subscriber Group (CSG), UEs for users in a home, etc.). An eNB used for a macro cell can be referred to as a macro eNB. An eNB used for a small cell can be referred to as a small cell eNB, pico eNB, femto eNB, or home eNB. An eNB can support one or more (e.g., two, three, four, etc.) cells (e.g., CCs). The UE can communicate with various types of base stations and network devices, including macro eNBs, small cell eNBs, and relay base stations.

[0156] The wireless communication system or system described herein can support synchronous or asynchronous operation. For synchronous operation, base stations can have similar frame timings, and transmissions from different base stations can be approximately time-aligned. For asynchronous operation, base stations can have different frame timings, and transmissions from different base stations can be time-disaligned. The techniques described herein can be used for both synchronous and asynchronous operation.

[0157] The DL transmission described in this article can also be referred to as a forward link transmission, while the UL transmission can also be referred to as a reverse link transmission. Each communication link described in this article (including, for example) Figure 1 and Figure 2The wireless communication systems 100 and 200 described herein may include one or more carriers, wherein each carrier may be a signal composed of multiple subcarriers (e.g., waveform signals of different frequencies). Each modulated signal may be transmitted on a different subcarrier and may carry control information (e.g., reference signals, control channels, etc.), overhead information, user data, etc. The communication link described herein (e.g., Figure 1 The communication link 125 can use frequency division duplex (FDD) (e.g., using paired spectrum resources) or TDD operation (e.g., using unpaired spectrum resources) to send bidirectional communication. The frame structure can be defined for FDD (e.g., frame structure type 1) and for TDD (e.g., frame structure type 2).

[0158] Therefore, aspects of this disclosure can provide eCC DRS. It should be noted that these methods describe possible implementations, and the operations and steps can be rearranged or otherwise modified to make other implementations possible. In some examples, aspects from two or more methods can be combined.

[0159] The various illustrative boxes and modules described in conjunction with the disclosure herein can be implemented or performed using a general-purpose processor, digital signal processor (DSP), ASIC, field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware component, or any combination thereof, designed to perform the functions described herein. The general-purpose processor can be a microprocessor, but alternatively, the processor can be any conventional processor, controller, microcontroller, or state machine. The processor can also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, a combination of one or more microprocessors with a DSP core, or any other such configuration). Therefore, the functions described herein can be performed by one or more other processing units (or cores) on at least one integrated circuit (IC). In the various examples, different types of ICs (e.g., structured / platform ASICs, FPGAs, or other half-custom ICs) can be used, which can be programmed in any manner known in the art. The functionality of each unit can also be implemented, wholly or partially, using instructions embodied in memory and formatted for execution by one or more general-purpose or special-purpose processors.

[0160] In the accompanying drawings, similar components or features may have the same reference label. Furthermore, components of the same type can be distinguished by adding a dash after the reference label and a second label to differentiate them among similar components. If only the first reference label is used in the specification, the description applies to any similar component having the same first reference label, regardless of the second reference label.

Claims

1. A method for wireless communication in a system, the system supporting communication with a first group of devices using a first OFDM symbol duration associated with a first tone interval and communication with a second group of devices using a second OFDM symbol duration associated with a second tone interval, the method comprising: One or more discovery reference signals (DRS) are identified in a narrow band region of a carrier, wherein the one or more DRS use the first OFDM symbol duration and the first tone interval; Identify a second region of the carrier, wherein the second region supports the second OFDM symbol duration and the second tone interval, and wherein the first OFDM symbol duration is greater than the second OFDM symbol duration and the first tone interval is less than the second tone interval; and Communication is performed in the second region of the carrier using the second OFDM symbol duration and the second tone interval.

2. The method according to claim 1, wherein, The one or more DRS in the narrowband region of the carrier are identified using a first receiver operating according to the first OFDM symbol duration and the first tone interval, and wherein the communication in the second region of the carrier is using a second receiver operating according to the second OFDM symbol duration and the second tone interval.

3. The method according to claim 2, further comprising: The first receiver is used to perform a cell search or measurement procedure, wherein the one or more DRSs are identified at least in part based on the cell search or measurement procedure.

4. The method according to claim 1, further comprising: The one or more DRS and first system information SI messages are transmitted during a first time period using the first OFDM symbol duration and the first tone interval; as well as The second SI message is sent during the second time period using the second OFDM symbol duration and the second tone interval.

5. The method according to claim 4, wherein, The second SI message includes differences relative to the first SI message.

6. The method according to claim 4, further comprising: One or more additional DRSs are transmitted in a second channel using the first OFDM symbol duration and the first tone interval, wherein the second channel supports communication with the second group of devices.

7. The method according to claim 1, further comprising: During a first time period, one or more DRS and first system information (SI) messages are transmitted in a first channel of the carrier, wherein the first channel supports communication with the first group of devices and the second group of devices; and During the second time period, one or more additional DRS and second SI messages are transmitted in the first and second channels of the carrier, wherein the second channel supports communication with the second group of devices.

8. The method according to claim 1, further comprising: Receive measurement reports from user equipment (UE); as well as Based at least in part on the measurement report, determine the number of system bandwidth channels for neighboring base stations, determine whether the neighboring base station supports communication using the second OFDM symbol duration and the second tone interval, or determine whether the second OFDM symbol duration and the second tone interval are not supported by the neighboring base station.

9. The method according to claim 1, further comprising: Receive measurement reports from user equipment (UE); as well as The number of channels using system bandwidth by neighboring base stations is determined at least in part based on the measurement reports.

10. The method according to claim 9, wherein, The measurement report includes information about each channel, including the DRS used by the neighboring base station.

11. The method according to claim 1, further comprising: Multiple idle channel assessment (CCA) attempts on the main channel during the transmission window were unsuccessful. as well as Avoid sending the one or more DRSs during the transmission window.

12. The method according to claim 1, further comprising: It was determined that the first CCA attempt on the main channel of the carrier was unsuccessful; It was determined that the second CCA attempt on the non-primary channel of the carrier was successful; as well as The one or more DRSs are transmitted on the non-primary channel, at least in part, based on determining that the first CCA attempt is unsuccessful and determining that the second CCA attempt is successful, wherein the non-primary channel includes the narrowband region of the carrier.

13. The method according to claim 1, wherein, The one or more DRSs include an indication of whether communication using the first OFDM symbol duration and the first tone interval is supported by a channel including the narrowband region.

14. The method according to claim 1, further comprising: Whether a channel supports communication using the first OFDM symbol duration and the first tone interval is determined at least in part based on the following: the one or more DRS, SI messages, phase shifts between different pilots within the one or more DRS, the relative position of the secondary synchronization signal (SSS) within the DRS relative to the primary synchronization signal (PSS), or a successful decoding attempt of the SI message.

15. The method according to claim 1, further comprising: Identify a first transmission power level for the one or more DRSs, wherein the first transmission power level is independent of the bandwidth occupied by the transmission including the one or more DRSs; Identify the bandwidth of the carrier; and The second transmission power level for the area outside the bandwidth occupied by the transmission containing the one or more DRSs is adjusted at least in part based on the following: the first transmission power level for the one or more DRSs, the total transmission power for the carrier, or the bandwidth occupied by the transmission containing the one or more DRSs, or a combination thereof.

16. The method according to claim 1, wherein, The one or more DRSs include: primary synchronization signal (PSS), secondary synchronization signal (SSS), primary information block (MIB), cell-specific reference signal (CRS), channel state information reference signal (CSI-RS), or any combination thereof.

17. The method according to claim 1, wherein, The one or more DRSs are directed to the first group of devices and the second group of devices.

18. The method according to claim 1, wherein, The narrowband region of the carrier includes six or eight central resource blocks (RBs) of the carrier's channel.

19. The method according to claim 1, wherein, When the narrowband region is frequency-division multiplexed with the second region of the carrier, the narrowband region is defined by a first guard band and a second guard band.

20. An apparatus for wireless communication in a system, the system supporting communication with a first group of devices using a first OFDM symbol duration associated with a first tone interval and communication with a second group of devices using a second OFDM symbol duration associated with a second tone interval, the apparatus comprising: A unit for identifying one or more discovery reference signals (DRS) in a narrowband region of a carrier, wherein the one or more DRSs use the first OFDM symbol duration and the first tone interval; A unit for identifying a second region of the carrier, wherein the second region supports the second OFDM symbol duration and the second tone interval, and wherein the first OFDM symbol duration is greater than the second OFDM symbol duration and the first tone interval is less than the second tone interval; and A unit for communicating in the second region of the carrier using the second OFDM symbol duration and the second tone interval.

21. The apparatus according to claim 20, wherein, The unit for identifying one or more DRSs in the narrowband region of the carrier includes: a first receiver operating according to the first OFDM symbol duration and the first tone interval, and wherein the unit for communicating in the second region of the carrier includes: a second receiver operating according to the second OFDM symbol duration and the second tone interval.

22. The apparatus of claim 21, further comprising: A unit for performing a cell search or measurement process using the first receiver, wherein the unit for identifying the one or more DRSs is operable at least in part based on the cell search or measurement process.

23. The apparatus of claim 20, further comprising: A unit for transmitting one or more DRS and first system information SI messages during a first time period using the first OFDM symbol duration and the first tone interval; as well as A unit for transmitting a second SI message during a second time period using the second OFDM symbol duration and the second tone interval.

24. The apparatus according to claim 23, wherein, The second SI message contains differences relative to the first SI message.

25. The apparatus of claim 23, further comprising: A unit for transmitting one or more additional DRSs in a second channel using the first OFDM symbol duration and the first tone interval, wherein the second channel supports communication with the second group of devices.

26. The apparatus of claim 20, further comprising: A unit for transmitting one or more DRS and first system information (SI) messages in a first channel of the carrier during a first time period, wherein the first channel supports communication with the first group of devices and the second group of devices; and A unit for transmitting one or more additional DRS and second SI messages in the first and second channels of the carrier during a second time period, wherein the second channel supports communication with the second group of devices.

27. The apparatus of claim 20, further comprising: A unit for receiving measurement reports from user equipment (UE); as well as Units for determining, at least in part, the number of system bandwidth channels for a neighboring base station based on the measurement report, determining that the neighboring base station supports communication using the second OFDM symbol duration and the second tone interval, or determining that the second OFDM symbol duration and the second tone interval are not supported by the neighboring base station.

28. An apparatus for wireless communication in a system, the system supporting communication with a first group of devices using a first OFDM symbol duration associated with a first tone interval and communication with a second group of devices using a second OFDM symbol duration associated with a second tone interval, the system comprising: processor; Memory that is in electrical communication with the processor; as well as Instructions, which are stored in the memory and are operable when executed by the processor, to cause the device to: One or more discovery reference signals (DRS) are identified in a narrow band region of a carrier, wherein the one or more DRS use the first OFDM symbol duration and the first tone interval; Identify a second region of the carrier, wherein the second region supports the second OFDM symbol duration and the second tone interval, and wherein the first OFDM symbol duration is greater than the second OFDM symbol duration and the first tone interval is less than the second tone interval; and Communication is performed in the second region of the carrier using the second OFDM symbol duration and the second tone interval.

29. A non-transitory computer-readable medium storing code for wireless communication in a system supporting communication with a first group of devices using a first OFDM symbol duration associated with a first tone interval and communication with a second group of devices using a second OFDM symbol duration associated with a second tone interval, the code comprising instructions executable to: One or more discovery reference signals (DRS) are identified in a narrow band region of the carrier, wherein, The one or more DRSs use the first OFDM symbol duration and the first tone interval; Identify a second region of the carrier, wherein the second region supports the second OFDM symbol duration and the second tone interval, and wherein the first OFDM symbol duration is greater than the second OFDM symbol duration and the first tone interval is less than the second tone interval; and Communication is performed in the second region of the carrier using the second OFDM symbol duration and the second tone interval.

Images