US20140153509A1

US20140153509A1 - Method and apparatus for establishing proximity service communication in a wireless communication system

Info

Publication number: US20140153509A1
Application number: US14/092,684
Authority: US
Inventors: Yu-Hsuan Guo
Original assignee: Innovative Sonic Corp
Current assignee: Innovative Sonic Corp
Priority date: 2012-11-30
Filing date: 2013-11-27
Publication date: 2014-06-05
Also published as: TW201422044A; US20140153538A1; US9615361B2

Abstract

Methods and apparatuses are disclosed to establish proximity service communication between a first user equipment (UE) and a second UE. The method includes receiving, by the first UE, a signaling transmitted by an evolved Node B (eNB) to provide a radio resource for the first UE to transmit data directly to the second UE, wherein an indication of a Radio Network Temporary Identifier (RNTI) is included in the signaling. The method further includes transmitting, by the first UE, data via the radio resource to the second UE, wherein the data is scrambled by the RNTI.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/731,712 filed on Nov. 30, 2012, the entire disclosure of which is incorporated herein by reference.

FIELD

This disclosure generally relates to wireless communication networks, and more particularly, to methods and apparatuses for establishing proximity service communication in a wireless communication system.

BACKGROUND

With the rapid rise in demand for communication of large amounts of data to and from mobile communication devices, traditional mobile voice communication networks are evolving into networks that communicate with Internet Protocol (IP) data packets. Such IP data packet communication can provide users of mobile communication devices with voice over IP, multimedia, multicast and on-demand communication services.
An exemplary network structure for which standardization is currently taking place is an Evolved Universal Terrestrial Radio Access Network (E-UTRAN). The E-UTRAN system can provide high data throughput in order to realize the above-noted voice over IP and multimedia services. The E-UTRAN system's standardization work is currently being performed by the 3GPP standards organization. Accordingly, changes to the current body of 3GPP standard are currently being submitted and considered to evolve and finalize the 3GPP standard.

SUMMARY

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a diagram of a wireless communication system according to one exemplary embodiment.

FIG. 2 is a block diagram of a transmitter system (also known as access network) and a receiver system (also known as user equipment or UE) according to one exemplary embodiment.

FIG. 3 is a functional block diagram of a communication system according to one exemplary embodiment.

FIG. 4 is a functional block diagram of the program code of FIG. 3 according to one exemplary embodiment.

FIG. 5 is a block diagram of a direct mode data path in the Evolved Packet System (EPS) for communication between two UEs.

FIG. 6 is a block diagram of a locally-routed data path in the EPS for communication between two UEs when the UEs are served by the same evolved Node B (eNB).

FIG. 7 is an exemplary block diagram of a control path for network supported ProSe communication for UEs served by the same eNB.

FIG. 8 is another exemplary block diagram of a control path for network supported ProSe Communication for UEs served by different eNBs.

FIG. 9 is another exemplary block diagram of a control path for Public Safety ProSe Communication for UEs without network support.

FIG. 10 is a signaling flow diagram according to one exemplary embodiment.

FIG. 11 is a signaling flow diagram according to one exemplary embodiment.

FIG. 12 is a signaling flow diagram according to one exemplary embodiment.

FIG. 13 is a signaling flow diagram according to one exemplary embodiment.

DETAILED DESCRIPTION

The exemplary wireless communication systems and devices described below employ a wireless communication system, supporting a broadcast service. Wireless communication systems are widely deployed to provide various types of communication such as voice, data, and so on. These systems may be based on code division multiple access (CDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), 3GPP LTE (Long Term Evolution) wireless access, 3GPP LTE-A or LTE-Advanced (Long Term Evolution Advanced), 3GPP2 UMB (Ultra Mobile Broadband), WiMax, or some other modulation techniques.
In particular, the exemplary wireless communication systems devices described below may be designed to support one or more standards such as the standard offered by a consortium named “3rd Generation Partnership Project” referred to herein as 3GPP, including Document Nos. RP-121435, “Study on LTE Device to Device Proximity Discovery”; TR 22.803 V1.0.0, “Feasibility Study for Proximity Services (ProSe)”; TS 36.331 V11.1.0, “E-UTRA RRC protocol specification”; TS 36.321 V11.0.0, “E-UTRA MAC protocol specification”; and TS 36.213 V11.0.0, “E-UTRA Physical layer procedures”. The standards and documents listed above are hereby expressly incorporated herein.
FIG. 1 shows a multiple access wireless communication system according to one embodiment of the invention. An access network 100 (AN) includes multiple antenna groups, one including 104 and 106, another including 108 and 110, and an additional including 112 and 114. In FIG. 1, only two antennas are shown for each antenna group, however, more or fewer antennas may be utilized for each antenna group. Access terminal 116 (AT) is in communication with antennas 112 and 114, where antennas 112 and 114 transmit information to access terminal 116 over forward link 120 and receive information from access terminal 116 over reverse link 118. Access terminal (AT) 122 is in communication with antennas 106 and 108, where antennas 106 and 108 transmit information to access terminal (AT) 122 over forward link 126 and receive information from access terminal (AT) 122 over reverse link 124. In a FDD system, communication links 118, 120, 124 and 126 may use different frequency for communication. For example, forward link 120 may use a different frequency then that used by reverse link 118.
Each group of antennas and/or the area in which they are designed to communicate is often referred to as a sector of the access network. In the embodiment, antenna groups each are designed to communicate to access terminals in a sector of the areas covered by access network 100.
In communication over forward links 120 and 126, the transmitting antennas of access network 100 may utilize beamforming in order to improve the signal-to-noise ratio of forward links for the different access terminals 116 and 122. Also, an access network using beamforming to transmit to access terminals scattered randomly through its coverage causes less interference to access terminals in neighboring cells than an access network transmitting through a single antenna to all its access terminals.
An access network (AN) may be a fixed station or base station used for communicating with the terminals and may also be referred to as an access point, a Node B, a base station, an enhanced base station, an eNodeB, or some other terminology. An access terminal (AT) may also be called user equipment (UE), a wireless communication device, terminal, access terminal or some other terminology.
FIG. 2 is a simplified block diagram of an embodiment of a transmitter system 210 (also known as the access network) and a receiver system 250 (also known as access terminal (AT) or user equipment (UE)) in a MIMO system 200. At the transmitter system 210, traffic data for a number of data streams is provided from a data source 212 to a transmit (TX) data processor 214.
In one embodiment, each data stream is transmitted over a respective transmit antenna. TX data processor 214 formats, codes, and interleaves the traffic data for each data stream based on a particular coding scheme selected for that data stream to provide coded data.
The coded data for each data stream may be multiplexed with pilot data using OFDM techniques. The pilot data is typically a known data pattern that is processed in a known manner and may be used at the receiver system to estimate the channel response. The multiplexed pilot and coded data for each data stream is then modulated (i.e., symbol mapped) based on a particular modulation scheme (e.g., BPSK, QPSK, M-PSK, or M-QAM) selected for that data stream to provide modulation symbols. The data rate, coding, and modulation for each data stream may be determined by instructions performed by processor 230.
The modulation symbols for all data streams are then provided to a TX MIMO processor 220, which may further process the modulation symbols (e.g., for OFDM). TX MIMO processor 220 then provides N_Tmodulation symbol streams to N_Ttransmitters (TMTR) 222 a through 222 t. In certain embodiments, TX MIMO processor 220 applies beamforming weights to the symbols of the data streams and to the antenna from which the symbol is being transmitted.
Each transmitter 222 receives and processes a respective symbol stream to provide one or more analog signals, and further conditions (e.g., amplifies, filters, and upconverts) the analog signals to provide a modulated signal suitable for transmission over the MIMO channel. N_Tmodulated signals from transmitters 222 a through 222 t are then transmitted from N_Tantennas 224 a through 224 t, respectively.
At receiver system 250, the transmitted modulated signals are received by N_Rantennas 252 a through 252 r and the received signal from each antenna 252 is provided to a respective receiver (RCVR) 254 a through 254 r. Each receiver 254 conditions (e.g., filters, amplifies, and downconverts) a respective received signal, digitizes the conditioned signal to provide samples, and further processes the samples to provide a corresponding “received” symbol stream.
An RX data processor 260 then receives and processes the N_Rreceived symbol streams from N_Rreceivers 254 based on a particular receiver processing technique to provide N_T“detected” symbol streams. The RX data processor 260 then demodulates, deinterleaves, and decodes each detected symbol stream to recover the traffic data for the data stream. The processing by RX data processor 260 is complementary to that performed by TX MIMO processor 220 and TX data processor 214 at transmitter system 210.
A processor 270 periodically determines which pre-coding matrix to use (discussed below). Processor 270 formulates a reverse link message comprising a matrix index portion and a rank value portion.
The reverse link message may comprise various types of information regarding the communication link and/or the received data stream. The reverse link message is then processed by a TX data processor 238, which also receives traffic data for a number of data streams from a data source 236, modulated by a modulator 280, conditioned by transmitters 254 a through 254 r, and transmitted back to transmitter system 210.
At transmitter system 210, the modulated signals from receiver system 250 are received by antennas 224, conditioned by receivers 222, demodulated by a demodulator 240, and processed by a RX data processor 242 to extract the reserve link message transmitted by the receiver system 250. Processor 230 then determines which pre-coding matrix to use for determining the beamforming weights then processes the extracted message.
Turning to FIG. 3, this figure shows an alternative simplified functional block diagram of a communication device according to one embodiment of the invention. As shown in FIG. 3, the communication device 300 in a wireless communication system can be utilized for realizing the UEs (or ATs) 116 and 122 in FIG. 1, and the wireless communications system is preferably the LTE system. The communication device 300 may include an input device 302, an output device 304, a control circuit 306, a central processing unit (CPU) 308, a memory 310, a program code 312, and a transceiver 314. The control circuit 306 executes the program code 312 in the memory 310 through the CPU 308, thereby controlling an operation of the communications device 300. The communications device 300 can receive signals input by a user through the input device 302, such as a keyboard or keypad, and can output images and sounds through the output device 304, such as a monitor or speakers. The transceiver 314 is used to receive and transmit wireless signals, delivering received signals to the control circuit 306, and outputting signals generated by the control circuit 306 wirelessly.
FIG. 4 is a simplified block diagram of the program code 312 shown in FIG. 3 in accordance with one embodiment of the invention. In this embodiment, the program code 312 includes an application layer 400, a Layer 3 portion 402, and a Layer 2 portion 404, and is coupled to a Layer 1 portion 406. The Layer 3 portion 402 generally performs radio resource control. The Layer 2 portion 404 generally performs link control. The Layer 1 portion 406 generally performs physical connections.
For LTE or LTE-A systems, the Layer 2 portion may include a Radio Link Control (RLC) layer and a Medium Access Control (MAC) layer. The Layer 3 portion may include a Radio Resource Control (RRC) layer.
Device to device discovery (as discussed in RP-121435) and communication for proximity services are expected to be an important feature for LTE in future, e.g. in Rel-12. The discussion on the feasibility study for Proximity Services (ProSe) is ongoing and is discussed in 3GPP TR 22.803 V1.0.0. The objective of the study is quoted below:

- The objective is to study use cases and identify potential requirements for operator network controlled discovery and communications between UEs that are in proximity, under continuous network control, and are under 3GPP network coverage, for:
  - 1. Commercial/social use
  - 2. Network offloading
  - 3. Public Safety
  - 4. Integration of current infrastructure services, to assure the consistency of the user experience including reachability and mobility aspects
- Additionally, the study item will study use cases and identify potential requirements for
  - 5. Public Safety, in case of absence of EUTRAN coverage (subject to regional regulation and operator policy, and limited to specific public-safety designated frequency bands and terminals)

As discussed in 3GPP TR 22.803 V1.0.0, ProSe includes two main functions: ProSe Discovery and ProSe Communication. ProSe Discovery is a process that identifies that a UE is in proximity of another UE using Evolved Universal Terrestrial Radio Access (E-UTRA). ProSe Discovery shall support a minimum of three range classes—for example short, medium and maximum range. ProSe Communication is a communication between two UEs in proximity by means of a communication path established between the UEs. For example, the communication path could be established directly between the UEs or routed via local evolved Node B(s) (eNB(s)).
A UE that supports ProSe Discovery and/or ProSe Communication is called a ProSe-enabled UE.
ProSe Discovery may be either Open ProSe Discovery or Restricted ProSe Discovery. Open ProSe Discovery does not need explicit permission from the UE being discovered. Restricted ProSe Discovery needs explicit permission from the UE being discovered.
FIGS. 5 and 6 illustrate possible data paths for ProSe Communications. FIG. 5 illustrates a direct mode data path in the Evolved Packet System (EPS) for communication between two UEs 510, 520 in a system 500 is composed of two UEs 510, 520, two evolved Node B's (eNBs) 540, 550 and a serving gateway and/or packet data network gateway (SGW/PGW) 560. FIG. 6 illustrates a locally-routed data path in the EPS for communication between two UEs 510, 520 when the UEs are served by the same eNB 540. In FIG. 6, the system 600 may be composed of two UEs 510, 520, two eNBs 540, 550, and a SGW/PGW 560.
FIGS. 7-9 illustrate possible control paths for ProSe Communications. FIG. 7 is an exemplary block diagram of a control path for network supported ProSe communication for UEs 510, 520 served by the same eNB 540. As shown in FIG. 7, the UEs 510, 520 communicate with the same eNB 540, which in turn communicates with an Evolved Packet Core (EPC) 710. FIG. 8 is another exemplary block diagram of a control path for network supported ProSe Communication for UEs 510, 520 served by different eNBs 540, 550. As shown in FIG. 8, a first UE 510 communicates with a first eNB 540, and the second UE 520 communicated with a second eNB 550. Each of the eNBs 540, 550 then communicates with the EPC 710. FIG. 9 is another exemplary block diagram of a control path for Public Safety ProSe Communication for UEs 510, 520 without network support. As shown in FIG. 9, the UEs 510, 520 communicate with a Public Safety Radio Resource Controller 910. Alternatively, for public safety purposes, a Public Safety UE can relay the radio resource management control information for other Public Safety UEs that do not have network coverage.
As discussed in 3GPP TR 22.803 V1.0.0 provides some ProSe Communication requirements as quoted below:
5.1.6.5 Potential Requirements
Requirements for E-UTRA ProSe Communications

- The system shall be capable of establishing a new user traffic session with an E-UTRA ProSe Communication path, and maintaining both of the E-UTRA ProSe Communication path and the infrastructure path simultaneously, when the UEs are determined to be in range allowing ProSe Communication.
  - Note: ProSe specifications should take into account the relative speed of ProSe-enabled UEs.
- The system shall be capable of moving a user traffic session from the infrastructure path to an E-UTRA ProSe Communication path, when the ProSe-enabled UEs are determined to be in range allowing ProSe Communication.
- The system shall be capable of monitoring the communication characteristics (e.g. channel condition, QoS of the path, volume of the traffic etc.) on the E-UTRA ProSe communication path, regardless of whether there is data transferred via infrastructure path.
- The system shall be capable of moving a user traffic session from an E-UTRA ProSe communication path to an infrastructure path. At a minimum, this functionality shall support the case when the E-UTRA ProSe Communication path is no longer feasible. The user shall not perceive the switching of user traffic sessions between the E-UTRA ProSe Communication and infrastructure paths.
- The system shall be capable of switching each flow it is aware of between the E-UTRA ProSe Communication and the infrastructure paths, independently.
- The establishment of a user traffic session on the E-UTRA ProSe Communication path and the switching of user traffic between an E-UTRA Prose Communication path and an infrastructure path are under control of the network.
- The Radio Access Network shall control the radio resources associated with the E-UTRA ProSe Communication path.
- The ProSe mechanism shall allow the operator to change the communication path of a user traffic session without affecting the QoS of the session.
- The ProSe mechanism shall allow the operator to change the communication path of one user traffic session of a UE without affecting the communication paths of other ongoing user traffic sessions.
- The ProSe mechanism shall allow the operator to change the communication path of a user traffic session according to decisions based upon the QoS requirements of the session and the QoS requirements of other ongoing sessions.
- The system shall be capable of selecting the most appropriate communications path, according to operator preferences. The criteria for evaluation may include the following, although not restricted to:
  - System-specific conditions: backhaul link, supporting links or core node (EPC) performance;
  - Cell-specific conditions: cell loading;
  - UE to UE conditions: communication range, channel conditions and achievable QoS;
  - UE to eNB conditions: communication range, channel conditions and achievable QoS;
  - Service-type conditions: APN, service discriminator.

6.2 Additional Operational Requirements

- ProSe services are available to ProSe-enabled UEs that are registered to a PLMN, and are under coverage of the E-UTRAN of said PLMN, potentially served by different eNBs. In this case E-UTRAN resources involved in ProSe services will be under real time 3GPP network control.
- Subject to operator policy and user consent, a ProSe-enabled UE should be capable of establishing the E-UTRAN infrastructure path and ProSe communication path concurrently.
- The network should be able to collect Discovery information regarding which ProSe-enabled UEs are discovered to be in proximity of a given UE. Restrictions from contracts and regulation on data collection apply.
- ProSe services are not available to ProSe-enabled UEs out of E-UTRAN coverage except in the following case:
- ProSe-enabled public safety UEs can use ProSe services when operating on public safety spectrum dedicated to ProSe services even when not under E-UTRAN coverage. In this case, at least a one-time pre-authorization to use ProSe services is needed.
- Re-authorization and specific configurations, including spectrum configurations, of public safety UEs shall be subject to public safety operator policy.
- When Operating ProSe, the EPS shall be able to support regional or national regulatory requirements, (e.g. lawful interception, PWS).

6.3 Additional Charging Requirements

- When a ProSe-enabled UE uses ProSe Communication, the operator shall be able to collect accounting data for ProSe communication including:
  - activation/deactivation of the ProSe Communication feature
  - ProSe Communication initiation/termination
  - ProSe Communication duration, and amount of data transferred
- The above requirements do not apply to public safety communications outside network coverage.

In the wireless communication technology, there are methods for transmission and reception of proximity detection signal for peer discovery. In one method, peer discovery is a UE performs peer discovery with the assistance from the network. The network may send a notification to the UE of a match for the UE seeking a peer. Additionally, the notification may also convey resources and/or other parameters to use for peer discovery. Upon receiving the notification, the UE may then perform peer discovery using proximity detection signals. In one design, the proximity detection signal is based on the Physical Uplink Shared Channel (PUSCH), which includes a proximity detection reference signal and a data portion. The data portion of the proximity detection signal may include information such as identity of the UE transmitting the proximity detection signal, services requested by the UE, services offered by the UE, and/or location information for the UE.
In the wireless communication technology, methods for indicating wireless network resources for communicating peer discovery signals are known. These methods provide exemplary time structures and channels that may be utilized for peer-to-peer discovery and communication. The time structures may have varying levels of frames of time, in which each lower frame level is further subdivided into different periods of time. Similarly, the channels for peer discovery may be subdivided into subchannels, in which each of the subchannels may be composed of a plurality of blocks for communicating peer discovery information. For example, a peer discovery channel may include subchannels such as a long range peer discovery channel, medium range peer discovery channel, or a short range peer discovery channel.
When a UE is turned on, the UE listens to the peer discovery channel and selects a set of blocks from a subchannel. Depending upon the character of the subchannel, the UE may transmit peer discovery signals or listen for peer discovery signals sent from other UEs.
Currently, only use cases and requirements for ProSe Communication are specified in 3GPP TR 22.803 V1.0.0. Methods to realize ProSe Communication and fulfil those requirements are not yet designed. One main difference compared to the existing peer to peer connection technologies, such as Bluetooth, WiFi ad hoc, WiFi Direct, or the like, is that LTE network should be in control of the ProSe Communication functions. For example, the LTE network should be in control of establishing of a new user traffic session with an E-UTRA ProSe Communication path; moving a user traffic session between infrastructure path and E-UTRA ProSe Communication path; real time control for the radio resources associated with the E-UTRA ProSe Communication path; and/or collecting accounting data including activation/deactivation of the ProSe Communication feature, ProSe Communication initiation/termination, and ProSe Communication duration, and amount of data transferred.
In order to realize ProSe Communication with involvement of network control, new signaling is required. According to various embodiments, the content of the signaling and the signaling flow is designed to fulfil requirements for ProSe Communication as set forth in 3GPP TR 22.803 V1.0.0. Additionally, the various embodiments disclosed herein provide ProSe Communication based on existing mechanisms, e.g. procedures, channels, or etc., as many as possible to reduce the complexity of introducing ProSe Communication into LTE.
Signaling
In one embodiment, UE1 and UE2 connect to eNB(s). When UE1 communicates with UE2 via ProSe Communication, one or multiple signaling described below ((a)-(h)) may be used, for example, to support dynamic scheduling, Semi-Persistent scheduling, or retransmission.
(a) A Signaling Transmitted by eNB Provides Radio Resource, e.g. Uplink Grant, for UE1 to Transmit Data Directly to UE2.
In one embodiment, the signaling can be a Physical Downlink Control Channel (PDCCH) or Enhanced Physical Downlink Control Channel (EPDCCH) signaling (as described in 3GPP TS 36.321 V11.0.0 and 3GPP TS 36.213 V11.0.0).
In one embodiment, the signaling may be addressed to a (pre-configured) Radio Network Temporary Identifier (RNTI) for ProSe Communication, UE1's Cell Radio Network Temporary Identifier (C-RNTI) (as described in 3GPP TS 36.321 V11.0.0), or Semi-Persistent Scheduling Radio Network Temporary Identifier (SPS-RNTI) (as described in 3GPP TS 36.321 V11.0.0).
In embodiment, the signaling may include an indication to indicate that (1) the radio resource is for ProSe Communication; (2) the RNTI, e.g. a (pre-configured) RNTI for ProSe Communication or UE1's C-RNTI or UE2's C-RNTI or SPS-RNTI, be used to scramble data transmitted via the radio resource; (3) the power (setting) to be used to transmit data via the radio resource, e.g. using power (setting) corresponding to ProSe Communication; (4) the radio resource is used to carry data from a specific Radio Bearer (RB) (as described in 3GPP TS 36.331 V11.1.0); or (5) the RB for which its data can be carry by the radio resource.
Based on the indication, UE1 may use a different calculation method (i.e., comparing with uplink grant allocation signaling for infrastructure path) to derive the radio resource from the signaling.
(b) A Signaling Transmitted by eNB Indicates UE2 to Receive a Data Transmission Directly from UE1, e.g., See (c) Below.
In one embodiment, the signaling can be a PDCCH or EPDCCH signaling, e.g. for downlink assignment.
In one embodiment, the signaling may be addressed to a (pre-configured) RNTI for ProSe Communication, UE2's C-RNTI, or SPS-RNTI.
In one embodiment, the signaling may include an indication to indicate that (1) the data transmission is ProSe Communication; (2) the RNTI, e.g. a (pre-configured) RNTI for ProSe Communication or UE1's C-RNTI or UE2's C-RNTI or SPS-RNTI, to be used to de-scramble the data; (3) the power (setting) to be used to transmit an acknowledgement for reception of the data, e.g. using power (setting) corresponding to ProSe Communication; or (4) the key(s) and/or algorithm(s) (as described in 3GPP TS 36.331 V11.1.0) to be used to decipher the data and/or check the integrity of the data.
Based on the indication, UE2 may use different calculation method (comparing with downlink assignment signaling for infrastructure path) to derive the radio resource used to transmit the data from the signaling.
In an alternate embodiment, the signaling may not always be required for a data transmission if Semi-Persistent Scheduling (as described in 3GPP TS 36.321 V11.0.0) is used.
(c) Data Directly Transmitted from UE1 to UE2 Via the Received Radio Resource.
In one embodiment, the radio resource (only) carries data from a (preconfigured) specific RB(s). The data from those RB(s) may not be (allowed to be) carried by radio resource not for ProSe Communication.
In one embodiment, the radio resource does not carry one or more of the following: the Buffer Status Report (BSR) (as described in 3GPP TS 36.321 V11.0.0), Power Headroom Report (PHR) (as described in 3GPP TS 36.321 V11.0.0), Channel Quality Indicator (CQI), and/or Channel State Information (CSI).
In one embodiment, UE1 may use PUSCH or a channel for ProSe Communication to transmit the data.
In one embodiment, the data may be scrambled by a (pre-configured) RNTI for ProSe Communication or UE1's C-RNTI or UE2's C-RNTI or SPS-RNTI.
In one embodiment, UE2 may receive (b) and (c), as described above, in the same TTI.
In one embodiment, UE2 may receive (g) as described below and (c) as described above in the same TTI.
(d) Providing an Acknowledgement, e.g. Hybrid Automatic Repeat Request Acknowledgement (HARQ ACK) or Negative Acknowledgement (NACK) (as Described in 3GPP TS 36.321 V11.0.0), by UE2 to Indicate Whether the Reception of the Data is Successful or not.
In one embodiment, the acknowledgement can be transmitted via Physical Uplink Control Channel (PUCCH).
In one embodiment, UE1 and/or eNB may receive the acknowledgement.
In one embodiment, UE1 may use different calculation method (comparing with reception of PHICH) to derive the radio resource used to transmit the acknowledgement from (a), as described above.
In one embodiment, the radio resource used to transmit the acknowledgement may be pre-configured.
In one embodiment, the interval between (a) and (d) (as described herein) may be eight (8) subframes (Frequency Division Duplex (FDD)) or k+4 subframes (Time Division Duplex (TDD)) (as described in 3GPP TS 36.213 V11.0.0).
(e) A Signaling Transmitted by eNB Indicates to UE2 to Receive a Retransmission of the Data Directly from UE1, e.g., See (f) as Described Below.
In one embodiment, the signaling may be addressed to a (pre-configured) RNTI for ProSe Communication, UE2's C-RNTI, or SPS-RNTI.
In one embodiment, the signaling may be transmitted if an acknowledgement with NACK was received, for example as described in (d) above.
(f) Data Directly Retransmitted from UE1 to UE2.
In one embodiment, UE1 may use PUSCH or a channel for ProSe Communication to retransmit the data.
In one embodiment, the data may be scrambled by a (pre-configured) RNTI for ProSe Communication or UE1's C-RNTI or UE2's C-RNTI or SPS-RNTI.
In one embodiment, the retransmission may be transmitted if an acknowledgement with NACK was received, as described in (d) above.
In one embodiment, the interval between (c) as described above and (f) described herein may be eight (8) subframes (FDD) or k+4 subframes (TDD).
In one embodiment, UE2 may receive (e) as described above and (f) as described herein in the same TTI.
In one embodiment, UE2 may receive (h) as describe below and (f) as described herein in the same TTI.
(g) A Signaling Transmitted by UE1 Indicates UE2 to Receive a Data Transmission Directly from UE1, e.g., See (c) as Described Above.
In one embodiment, the signaling can be a Physical Downlink Control Channel (PDCCH) signaling or Enhanced Physical Downlink Control Channel (EPDCCH) signaling or a signaling transmitted via a control channel for ProSe Communication, e.g. for downlink assignment.
In one embodiment, the signaling may be addressed to a (pre-configured) RNTI for ProSe Communication, UE2's C-RNTI, or SPS-RNTI.
In one embodiment, the signaling may include an indication to indicate: (1) the data transmission is ProSe Communication; (2) the RNTI, e.g. a (pre-configured) RNTI for ProSe Communication or UE1's C-RNTI [4] or UE2's C-RNTI [4] or SPS-RNTI [4], to be used to de-scramble the data; (3) the power (setting) to be used to transmit an acknowledgement for reception of the data, e.g. using power (setting) corresponding to ProSe Communication; or (4) the key(s) and/or algorithm(s) to be used to decipher the data and/or check the integrity of the data.
Based on the indication, UE2 may use different calculation method (comparing with downlink assignment signaling for infrastructure path) to derive the radio resource used to transmit the data from the signaling.
In some embodiments, the signaling may not always be required for a data transmission if Semi-Persistent Scheduling is used.
(h) a Signaling Transmitted by UE1 Indicates UE2 to Receive a Retransmission of the Data Directly from UE1, e.g., See (f) as Described Above.
In one embodiment, the signaling may be addressed to a (pre-configured) RNTI for ProSe Communication, UE2's C-RNTI, or SPS-RNTI.
In one embodiment, the signaling may be transmitted if an acknowledgement with NACK was received, e.g. see (d) as described above.
In one embodiment, UE1 and UE2 may connect to different eNBs, for example, UE1 is connected to eNB1 and UE2 is connected to eNB2. Accordingly, signaling as described in (a) and (b) may be transmitted by different eNBs. By way of example and not of limitation, signal (a) is transmitted by a first eNB and signal (b) is transmitted by a second eNB.
In one embodiment, the UE transmission power used for ProSe Communication is controlled by eNB. In one embodiment, eNB may be based on the channel condition report, e.g. CQI/CSI report, for ProSe Communication received from the UE to change the transmission power. For example, but not of limitation, UE2 may provide a report to eNB based on the measurement of the channel condition between UE1 and UE2. Then, eNB adjusts the transmission power of UE1 based on the received report.
In one embodiment, the ProSe Communication mentioned above can be E-UTRA ProSe Communication. In some embodiments, the ProSe Communication described above uses a path directly between UEs.
Signaling Flow.
FIGS. 10-13 illustrate various embodiments of signaling flow to realize ProSe Communication. In FIG. 10, eNB 1030 provides a radio resource 1040, e.g. via PDCCH, for UE1 1020 to transmit data to UE2 1010. As shown in FIG. 10, eNB 1030 transmits a signaling 1050, e.g. via PDCCH, to inform UE2 1010 to receive a new data transmission, and UE1 1020 transmits data 1060 via the received radio resource to UE2 1010. UE2 1010 responds with an acknowledgement 1070, e.g. via PUCCH, to indicate whether the data is received correctly or not. As shown in FIG. 10, UE1 1020 and eNB 1030 may decide whether to perform retransmission 1080, 1090 based on the received acknowledgement 1070.
In FIG. 11, eNB 1030 provides a radio resource 1040, e.g. via PDCCH, for UE1 1020 to transmit data to UE2 1010. As shown in FIG. 11, UE1 1020 transmits a signaling 1120 to inform UE2 1010 to receive a new data transmission, and UE1 transmits data 1060 via the received radio resource to UE2. UE2 1010 responds with an acknowledgement 1070, e.g. via PUCCH, to indicate whether the data is received correctly or not. UE1 1020 may decide whether to transmit an indication of data retransmission 1090 and perform retransmission 1130 based on the received acknowledgement 1070. Optionally, eNB may monitor the acknowledgement 1110 to evaluate channel quality or QoS.
In FIG. 12, the eNB 1030 provides a radio resource 1040, e.g. via PDCCH, for UE1 1020 to transmit data to UE2 1010. As shown in FIG. 12, eNB 1030 transmits a signaling 1050, e.g. via PDCCH, to inform UE2 1010 to receive a new data transmission, and UE1 1020 transmits data 1060 via the received radio resource to UE2 1010. UE2 1010 responds with an acknowledgement 1070, e.g. via PUCCH, to indicate whether the data is received correctly or not. UE1 1020 may decide whether to perform retransmission 1090 in a fixed timing based on the received acknowledgement. Since the retransmission timing is known by UE2 1010, no signaling to inform a retransmission is required. Optionally, eNB 1030 may monitor the acknowledgement 1110 to evaluate channel quality or QoS.
In FIG. 13, eNB 1030 provides a radio resource 1040, e.g. via PDCCH, for UE1 1020 to transmit data to UE2 1010. As shown in FIG. 13, UE1 1020 transmits a signaling 1120 to inform UE2 1010 to receive a new data transmission, and UE1 transmits data 1060 via the received radio resource to UE2. UE2 1010 responds with an acknowledgement 1070, e.g. via PUCCH, to indicate whether the data is received correctly or not. UE1 1020 may decide whether to perform retransmission 1090 in a fixed timing based on the received acknowledgement. Since the retransmission timing is known by UE2 1010, no signaling to inform a retransmission is required. Optionally, eNB 1030 may monitor the acknowledgement 1110 to evaluate channel quality or QoS.
Referring back to FIGS. 3 and 4, the device 300 includes a program code 312 stored in memory 310. In one embodiment, the CPU 308 could execute the program code 312 (i) to receive, by the first UE, a signaling transmitted by a eNB to provide radio resource for the first UE to transmit data directly to the second UE, wherein an indication of a RNTI is included in the signaling, and (ii) to transmit, by the first UE, data via the radio resource to the second UE, wherein the data is scrambled by the RNTI. In another embodiment, the CPU 308 could execute the program code 312 (i) to receive, by the first UE, a first signaling transmitted by a eNB to provide radio resource for the first UE to transmit data directly to the second UE, (ii) to transmit, by the first UE, a second signaling to the second UE to inform the second UE to receive data directly transmitted from the first UE, and (iii) to transmit, by the first UE, the data via the radio resource to the second UE.
In addition, the CPU 308 can execute the program code 312 to perform all of the above-described actions and steps or others described herein.
Various aspects of the disclosure have been described above. It should be apparent that the teachings herein may be embodied in a wide variety of forms and that any specific structure, function, or both being disclosed herein is merely representative. Based on the teachings herein one skilled in the art should appreciate that an aspect disclosed herein may be implemented independently of any other aspects and that two or more of these aspects may be combined in various ways. For example, an apparatus may be implemented or a method may be practiced using any number of the aspects set forth herein. In addition, such an apparatus may be implemented or such a method may be practiced using other structure, functionality, or structure and functionality in addition to or other than one or more of the aspects set forth herein. As an example of some of the above concepts, in some aspects concurrent channels may be established based on pulse repetition frequencies. In some aspects concurrent channels may be established based on pulse position or offsets. In some aspects concurrent channels may be established based on time hopping sequences. In some aspects concurrent channels may be established based on pulse repetition frequencies, pulse positions or offsets, and time hopping sequences.
Those of skill in the art would understand that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.
Those of skill would further appreciate that the various illustrative logical blocks, modules, processors, means, circuits, and algorithm steps described in connection with the aspects disclosed herein may be implemented as electronic hardware (e.g., a digital implementation, an analog implementation, or a combination of the two, which may be designed using source coding or some other technique), various forms of program or design code incorporating instructions (which may be referred to herein, for convenience, as “software” or a “software module”), or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure.
In addition, the various illustrative logical blocks, modules, and circuits described in connection with the aspects disclosed herein may be implemented within or performed by an integrated circuit (“IC”), an access terminal, or an access point. The IC may comprise a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, electrical components, optical components, mechanical components, or any combination thereof designed to perform the functions described herein, and may execute codes or instructions that reside within the IC, outside of the IC, or both. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.
It is understood that any specific order or hierarchy of steps in any disclosed process is an example of a sample approach. Based upon design preferences, it is understood that the specific order or hierarchy of steps in the processes may be rearranged while remaining within the scope of the present disclosure. The accompanying method claims present elements of the various steps in a sample order, and are not meant to be limited to the specific order or hierarchy presented.
The steps of a method or algorithm described in connection with the aspects disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module (e.g., including executable instructions and related data) and other data may reside in a data memory such as RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a hard disk, a removable disk, a CD-ROM, or any other form of computer-readable storage medium known in the art. A sample storage medium may be coupled to a machine such as, for example, a computer/processor (which may be referred to herein, for convenience, as a “processor”) such the processor can read information (e.g., code) from and write information to the storage medium. A sample storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in user equipment. In the alternative, the processor and the storage medium may reside as discrete components in user equipment. Moreover, in some aspects any suitable computer-program product may comprise a computer-readable medium comprising codes relating to one or more of the aspects of the disclosure. In some aspects a computer program product may comprise packaging materials.
While the invention has been described in connection with various aspects, it will be understood that the invention is capable of further modifications. This application is intended to cover any variations, uses or adaptation of the invention following, in general, the principles of the invention, and including such departures from the present disclosure as come within the known and customary practice within the art to which the invention pertains.

Claims

1. A method for establishing proximity service communication between a first user equipment (UE) and a second UE, the method comprising:

receiving, by the first UE, a signaling transmitted by an evolved Node B (eNB) to provide a radio resource for the first UE to transmit data directly to the second UE, wherein an indication of a Radio Network Temporary Identifier (RNTI) is included in the signaling; and

transmitting, by the first UE, data via the radio resource to the second UE, wherein the data is scrambled by the RNTI.

2. The method of claim 1, wherein the signaling is a Physical Downlink Control Channel (PDCCH) or Enhanced Physical Downlink Control Channel (EPDCCH) signaling.

3. The method of claim 1, wherein an indication about the radio resource is for the proximity service communication is included in the signaling.

4. The method of claim 1, wherein an indication of power to be used to transmit the data is included in the signaling.

5. The method of claim 1, wherein an indication of a radio bearer, whose data to be carried by the radio resource, is included in the signaling.

6. A communication device for establishing proximity service communication between the communication device and a user equipment (UE), the communication device comprising:

a control circuit;

a processor installed in the control circuit;

a memory installed in the control circuit and operatively coupled to the processor;

wherein the processor is configured to execute a program code stored in memory to establish the proximity service communication by:

receiving a signaling transmitted by an evolved Node B (eNB) to provide a radio resource for the communication device to transmit data directly to the UE, wherein an indication of a Radio Network Temporary Identifier (RNTI) is included in the signaling; and

transmitting data via the radio resource to the UE, wherein the data is scrambled by the RNTI.

7. The communication device of claim 6, wherein the signaling is a Physical Downlink Control Channel (PDCCH) or Enhanced Physical Downlink Control Channel (EPDCCH) signaling.

8. The communication device of claim 6, wherein an indication about the radio resource is for the proximity service communication is included in the signaling.

9. The communication device of claim 6, wherein an indication of power to be used to transmit the data is included in the signaling.

10. The communication device of claim 6, wherein an indication of a radio bearer, whose data to be carried by the radio resource, is included in the signaling.

11. A method for establishing proximity service communication between a first user equipment (UE) and a second UE, the method comprising:

receiving, by the first UE, a first signaling transmitted by an evolved Node B (eNB) to provide a radio resource for the first UE to transmit data directly to the second UE;

transmitting, by the first UE, a second signaling to the second UE to inform the second UE to receive data directly transmitted from the first UE; and

transmitting, by the first UE, the data via the radio resource to the second UE.

12. The method of claim 11, wherein the second signaling is a Physical Downlink Control Channel (PDCCH) or Enhanced Physical Downlink Control Channel (EPDCCH) signaling or a signaling transmitted via a control channel for the proximity service communication.

13. The method of claim 11, wherein an indication of a Radio Network Temporary Identifier (RNTI) to be used to de-scramble the data is included in the second signaling.

14. The method of claim 11, wherein an indication of power to be used to transmit an acknowledgement for reception of the data is included in the second signaling.

15. The method of claim 11, wherein an indication of a key and/or an algorithm to be used to decipher the data and/or check the integrity of the data is included in the second signaling.

16. A communication device for establishing proximity service communication between the communication device and a user equipment (UE), the communication device comprising:

a control circuit;

a processor installed in the control circuit;

receiving a first signaling transmitted by an evolved Node B (eNB) to provide a radio resource for the communication device to transmit data directly to the UE;

transmitting a second signaling to the UE to inform the UE to receive data directly transmitted from the communication device; and

transmitting the data via the radio resource to the UE.

17. The communication device of claim 16, wherein the second signaling is a Physical Downlink Control Channel (PDCCH) or Enhanced Physical Downlink Control Channel (EPDCCH) signaling or a signaling transmitted via a control channel for the proximity service communication.

18. The communication device of claim 16, wherein an indication of a Radio Network Temporary Identifier (RNTI) to be used to de-scramble the data is included in the second signaling.

19. The communication device of claim 16, wherein an indication of power to be used to transmit an acknowledgement for reception of the data is included in the second signaling.

20. The communication device of claim 16, wherein an indication of a key and/or an algorithm to be used to decipher the data and/or check the integrity of the data is included in the second signaling.