BR112016021490B1 - TRANSMISSION AND SCHEDULING ASSIGNMENT CONTENT IN WIRELESS COMMUNICATIONS - Google Patents

Abstract

TRANSMISSION AND SCHEDULE ASSIGNMENT CONTENT IN WIRELESS COMMUNICATIONS These are methods, systems and devices for transmissions and retransmissions of schedule assignment (SA) information and for content of SA transmissions. SAs can be transmitted during an initial communications period, followed by data transmissions for a certain period of time. A device may monitor for transmissions during the SA period and then monitor for data transmissions during periods indicated in a received SA. The SAs may be retransmitted according to a retransmission standard that may provide time or frequency diversity standards so as to improve reception of the SAs at a receiving device. Retransmission patterns can be determined based on a resource from an SA resource group that is used for an initial SA transmission.

Description

CROSS REFERENCES

[0001] This Patent Application claims the priority of Patent Application No. U.S. 14/608,851 with Tavildar et al., entitled "Scheduling Assignment Content and Transmission in Wireless Communications", filed on January 29, 2015, and the Provisional Patent Application No. U.S. 61/955,674 with Tavildar et al, entitled "Scheduling Assignment Content and Transmission in Wireless Communications", filed on March 19, 2014; each of which is assigned to the assignee thereof.

BACKGROUND

[0002] Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be multiple access systems with the ability to 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) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, and division multiple access systems. orthogonal frequency control (OFDMA).

[0003] In general, a wireless multiple access communications system may include a number of base stations, each of which simultaneously supports communication to multiple mobile devices or other user equipment (UE) devices. Base stations can communicate with UEs on both downstream and upstream links. Each base station has a coverage range, which can be called the cell coverage area. Device-to-device (D2D) communications involve direct wireless communications between UEs both within and beyond the coverage area of a base station. D2D communications can be facilitated by scheduling transmissions from a base station if devices are within a coverage area. In some cases, D2D communications are used by public safety officials such as police, fire and rescue teams, etc.

[0004] In many situations, the UEs used in D2D communications are mobile devices that are battery operated. Consequently, energy savings in such devices is a significant consideration in device operation in order to provide an improved operational lifespan between charges of a battery. Additionally, wireless transmissions in D2D communications may encounter interference from various sources, including wireless network base stations and other UEs that may be about to transmit, for example. Thus, it would be desirable for D2D communications to provide improved power saving techniques as well as providing improved interference mitigation.

SHORT DESCRIPTION

[0005] The features described generally refer to one or more improved systems, methods or apparatus for transmissions and retransmissions of schedule assignment (SA) information and for content of SA transmissions. According to several examples, SAs may be transmitted during an initial communications period, followed by data transmissions for a certain period of time. A device may monitor for transmissions during the SA period and then monitor for data transmissions during periods indicated in a received SA. In certain examples, the SAs may be retransmitted in accordance with a retransmission standard that may provide time or frequency diversity standards so as to improve receipt of the SAs at a receiving device. Retransmission patterns can be determined, for example, based on a resource from an SA resource group that is used for an initial SA transmission. SAs may include information relating to, for example, times and frequencies for data transmissions, or retransmission patterns for data transmissions. In some examples, a base station may transmit a message to a device that indicates resources that should be used for the scheduling assignment resource group.

[0006] In a first set of illustrative examples, a wireless communications method may include transmitting a scheduling assignment (SA) to one or more devices, wherein the SA indicates capabilities for a subsequent transmission of data to the one or more devices; and retransmitting the SA according to a predetermined retransmission pattern. SA is transmitted, for example, in a device-to-device broadcast (D2D) transmission. In certain examples, the retransmission pattern may include a fixed frequency hopping pattern, a fixed time pattern, or a combination thereof. The fixed frequency hopping pattern may be, in examples, a fixed time pattern indicated in a system information block (SIB) or a predefined pattern.

[0007] In certain examples, the method may also include determining a first block of resources within a group of SA resources to transmit the SA; and the retransmission pattern may be based, at least in part, on the first resource block. In some examples, the retransmission pattern may identify one or more of: multiple time resources within the SA resource group; or miscellaneous frequency resources within the SA resource group. In other examples, the SA resource group may include a plurality of Long Term Evolution (LTE) subframes.

[0008] In some examples, the method may also include receiving a grant for transmitting the SA from a base station, and transmitting the SA may include determining a first block of resources for transmitting the SA based, at least in part, on the grant. In some examples, the grant may include downlink control information (DCI) that has an index that identifies the first block of resources within the SA resource group. Such an index may be included, for example, in a DCI resource block assignment field.

[0009] In certain examples, the SA may include one or more of: a modulation and coding scheme (MCS) and a redundancy version (RV) for subsequent data transmission(s); a frequency hopping pattern for subsequent data transmission; a target identification (ID) for subsequent data transmission, wherein the subsequent data transmission can be scrambled using the target ID; an offset for the first data transmission relative to the SA transmission; a cyclic redundancy check (CRC) scrambled by the target ID; or an indicator of a last SA transmission.

[0010] In a second set of illustrative examples, an apparatus for wireless communications may include means for transmitting a scheduling assignment (SA) to one or more devices, wherein the SA indicates capabilities for a subsequent transmission of data to the one or more devices. or more devices; and means for retransmitting the SA in accordance with a predetermined retransmission pattern.

[0011] In certain examples, the apparatus may implement one or more aspects of the first set of illustrative examples described above.

[0012] In a third set of illustrative examples, an apparatus for wireless communications may include a processor; memory in electronic communication with the processor; and instructions stored in memory. The instructions may be executable by the processor to: transmit a scheduling assignment (SA) to one or more devices, wherein the SA indicates resources for a subsequent transmission of data to the one or more devices; and retransmitting the SA according to a predetermined retransmission pattern.

[0013] In certain examples, instructions may be configured to cause the processor to implement one or more aspects of the first set of illustrative examples described above.

[0014] In a fourth set of illustrative examples, a non-transitory computer-readable medium that stores instructions executable by a processor for: transmitting a scheduling assignment (SA) to one or more devices, wherein the SA indicates resources for a transmission subsequent data transfer to the one or more devices; and retransmitting the SA according to a predetermined retransmission pattern.

[0015] In certain examples, instructions may be configured to cause the processor to implement one or more aspects of the first set of illustrative examples described above.

[0016] In a fifth set of illustrative examples, a wireless communications method may include receiving a message from a base station; determining a group of scheduling assignment (SA) resources based, at least in part, on the message; and identifying a first block of resources within the SA resource group that is to be used to transmit an SA to one or more receivers. In certain examples, the SA may indicate resources for a subsequent transmission of data to the one or more receivers. The SA can be transmitted, for example, in a device-to-device broadcast (D2D) transmission.

[0017] In some examples, the method may also include transmitting a first SA to the one or more receivers during the first block of resources, wherein the first SA indicates resources for a subsequent transmission of data to the one or more receivers; and retransmitting the first SA according to a predetermined retransmission pattern. The retransmission pattern may include a fixed frequency hopping pattern, a fixed time pattern, or a combination thereof, which may be indicated in a system information block (SIB) or may be a predefined pattern, for example. In some examples, the retransmission pattern may identify one or more of several time resources within the SA resource group; or miscellaneous frequency resources within the SA resource group. The SA resource group may include a plurality of Long Term Evolution (LTE) subframes. In some examples, the message may include downlink control information (DCI) that has an index that identifies the first block of resources in the SA resource group. The index can be included in a DCI resource block assignment field, for example.

[0018] In certain examples, the SA may include one or more of a modulation and coding scheme (MCS) and a redundancy version (RV) for subsequent data transmission; a frequency hopping pattern for subsequent data transmission; a target identification (ID) for subsequent data transmission, wherein the subsequent data transmission is scrambled using the target ID; or an offset for the first data transmission relative to the SA transmission.

[0019] In a sixth set of illustrative examples, an apparatus for wireless communications may include means for receiving a message from a base station; means for determining a group of scheduling assignment (SA) resources based, at least in part, on the message; and means for identifying a first block of resources within the SA resource group that is to be used to transmit an SA to one or more receivers.

[0020] In certain examples, the apparatus may implement one or more aspects of the fifth set of illustrative examples described above.

[0021] In a seventh set of illustrative examples, an apparatus for wireless communications may include a processor; memory in electronic communication with the processor; and instructions stored in memory. Instructions may be executable by the processor to receive a message from a base station; determining a group of scheduling assignment (SA) resources based, at least in part, on the message; and identifying a first block of resources within the SA resource group that is to be used to transmit an SA to one or more receivers.

[0022] In certain examples, instructions may be configured to cause the processor to implement one or more aspects of the fifth set of illustrative examples described above.

[0023] In an eighth set of illustrative examples, a non-transitory computer-readable medium that stores instructions executable by a processor for receiving a message from a base station; determining a group of scheduling assignment (SA) resources based, at least in part, on the message; and identifying a first block of resources within the SA resource group that is to be used to transmit an SA to one or more receivers.

[0024] In certain examples, instructions may be configured to cause the processor to implement one or more aspects of the fifth set of illustrative examples described above.

[0025] In a ninth set of illustrative examples, a wireless communications method may include receiving a schedule assignment (SA) transmission, wherein the SA indicates resources for receiving a subsequent transmission of data; and receiving at least one retransmission from the SA in accordance with a predetermined retransmission pattern. In some examples, the method may also include combining the SA transmission and retransmission(s) to determine the SA. SA is transmitted, for example, in a device-to-device broadcast (D2D) transmission.

[0026] In certain examples, the predetermined retransmission pattern may include a fixed frequency hopping pattern, a fixed time pattern, or a combination thereof. The fixed frequency hopping pattern, fixed time pattern, or combination thereof may be indicated, for example, in a system information block (SIB) received from a transmitting device, or may be a predefined pattern.

[0027] In some examples, the method may also include determining a first resource block in which the SA transmission is received; and the retransmission pattern may be based, at least in part, on the first resource block. The SA may include one or more of: a modulation and coding scheme (MCS) and a redundancy version (RV) for subsequent data transmission; a frequency hopping pattern for subsequent data transmission; a target identification (ID) for subsequent data transmission, and the subsequent data transmission may be scrambled using the target ID; a cyclic redundancy check (CRC) scrambled by the target ID; or an offset to the first data transmission relative to the SA resource group or SA transmission.

[0028] In a tenth set of illustrative examples, an apparatus for wireless communications may include means for receiving a schedule assignment (SA) transmission, wherein the SA indicates resources for receiving a subsequent transmission of data; and means for receiving at least one retransmission of the SA in accordance with a predetermined retransmission pattern.

[0029] In certain examples, the apparatus may implement one or more aspects of the ninth set of illustrative examples described above.

[0030] In an eleventh set of illustrative examples, an apparatus for wireless communications may include a processor; memory in electronic communication with the processor; and instructions stored in memory. Instructions may be executable by the processor to: receive a schedule assignment (SA) transmission, wherein the SA indicates resources to receive a subsequent transmission of data; and receiving at least one retransmission from the SA in accordance with a predetermined retransmission pattern.

[0031] In certain examples, instructions may be configured to cause the processor to implement one or more aspects of the ninth set of illustrative examples described above.

[0032] In a twelfth set of illustrative examples, a non-transitory computer-readable medium that stores instructions executable by a processor for: receiving a scheduling assignment (SA) transmission, wherein the SA indicates resources for receiving a subsequent transmission data; and receiving at least one retransmission from the SA in accordance with a predetermined retransmission pattern.

[0033] In certain examples, instructions may be configured to cause the processor to implement one or more aspects of the ninth set of illustrative examples described above.

[0034] The further scope of applicability of the described methods and apparatus will become apparent from the detailed description, claims and drawings that follow. The detailed description and specific examples are given by way of illustration only, as various changes and modifications within the spirit and scope of the description will become apparent to those skilled in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] A further understanding of the nature and advantages of the present disclosure can be seen by reference to the following drawings. In the attached Figures, similar components or features may have the same reference marking. Furthermore, several components of the same type can be distinguished by following the reference marking by a dash and a second marking that distinguishes between similar components. If only the first reference marking is used in the specification, the description is applicable to any of the similar components that have the same first reference marking regardless of the second reference marking.

[0036] Figure 1 illustrates an example of a wireless communications system, in accordance with various aspects of the present disclosure;

[0037] Figure 2 illustrates an example of SA and groups of data resources for transmissions of SAs and data, in accordance with various aspects of the present disclosure;

[0038] Figure 3A illustrates an example of SA resource group resources for SA transmissions, in accordance with various aspects of the present disclosure;

[0039] Figure 3B illustrates another example of SA resource group resources for SA transmissions, in accordance with various aspects of the present disclosure;

[0040] Figure 4A illustrates an example of a data transmission that follows an SA, in accordance with various aspects of the present disclosure;

[0041] Figure 4B illustrates an example of multiple data transmissions following an SA, in accordance with various aspects of the present disclosure;

[0042] Figure 4C illustrates an example of data transmissions that have time and frequency diversity that follows an SA, in accordance with various aspects of the present disclosure;

[0043] Figure 5 shows a block diagram of a device that deploys SAs in D2D communications, in accordance with various aspects of the present disclosure;

[0044] Figure 6 shows a block diagram of a device for SA transmissions and retransmissions, in accordance with various aspects of the present disclosure;

[0045] Figure 7 shows a block diagram of a device for SA transmissions and content determination for SA transmissions, in accordance with various aspects of the present disclosure;

[0046] Figure 8 shows a block diagram of a device for SA transmissions and content determination for SA transmissions, in accordance with various aspects of the present disclosure;

[0047] Figure 9 illustrates a block diagram of a UE in a system for implementing SA transmissions and retransmissions, in accordance with various aspects of the present disclosure;

[0048] Figure 10 illustrates a block diagram of a base station in a system for implementing SA transmissions and retransmissions, in accordance with various aspects of the present disclosure;

[0049] Figure 11 shows a flowchart illustrating a method for SA transmissions and retransmissions, in accordance with various aspects of the present disclosure;

[0050] Figure 12 shows another flowchart illustrating a method for SA transmissions and retransmissions, in accordance with various aspects of the present disclosure;

[0051] Figure 13 shows another flowchart illustrating a method for SA transmissions and retransmissions, in accordance with various aspects of the present disclosure; It is

[0052] Figure 14 shows another flowchart illustrating a method for SA transmissions and retransmissions in accordance with various aspects of the present disclosure.

DETAILED DESCRIPTION

[0053] Features that generally refer to one or more improved systems, methods or apparatus for scheduling assignment transmissions and retransmissions (SAs) are described. To provide power savings in D2D communications, user equipment (UEs) can be provided with an SA that indicates resources that can be used to transmit data to the UE. SA information may be transmitted during a predetermined period followed by data transmissions for a predetermined period, which allows a UE to monitor transmissions during the SA period and monitor transmissions for portions of the data transmission period indicated for the UE by an SA.

[0054] In certain examples, the SA may be transmitted using an initial resource from an SA resource group, and retransmitted using one or more other SA resources from the SA resource group. The SA may indicate, for example, capabilities for a subsequent data transmission, and may be retransmitted one or more times in accordance with a predetermined retransmission pattern, which may include a fixed frequency hopping pattern or a fixed time pattern. The retransmission pattern may be indicated in a system information block (SIB) or may be predefined according to a wireless communications standard, for example. In some examples, a base station may transmit a message to a device that indicates resources that should be used for the SA resource group.

[0055] A retransmission pattern for SA retransmissions can be determined based on a resource block within the SA resource group used to transmit the SA. A receiver may determine the resource block and then determine the SA retransmission pattern, where different resource blocks for the first transmission may indicate different numbers of retransmissions, timing for retransmissions, or frequency hopping for retransmissions. Such retransmissions may provide improved receipt of SAs by combining the original SA transmission and the one or more retransmissions. Additionally, devices may simply monitor the SA resource group, and may turn off receiver components during periods of data transmission when the device is not programmed in accordance with the SA. The SA may include information related to timing, scrambling, transmission schemes, or frequency hopping for subsequent data transmissions, for example.

[0056] The techniques described in this document can be used for various wireless communications systems such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA and other systems. The terms "system" and "network" are often used interchangeably. A CDMA system can implement a radio technology such as CDMA2000, Universal Terrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000, IS-95 and IS-856 standards. Releases 0 and A of IS-2000 are commonly called CDMA2000 IX, IX, etc. IS-856 (TIA-856) is commonly called lxEV-DO of CDMA2000, High Rate Packet Data (HRPD), etc. UTRA includes Broadband CDMA (WCDMA) and other CDMA variants. A TDMA system can implement a radio technology such as Global System for Mobile Communications (GSM). An OFDMA system can implement radio technology such as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA), IEEE 802.11, IEEE 802.16, IEEE 802.20, Flash-OFDM", etc. UTRA and E -UTRA are parts of the Universal Mobile Telecommunications System (UMTS). 3GPP Long Term Evolution (LTE) and LTE Advanced (LTE-A) are new releases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A and GSM are described in documents from an organization called the “Third Generation Partnership Project” (3GPP). CDMA2000 and UMB are described in documents from an organization called the "Third Generation Partnership Project 2" (3GPP2). The techniques described in this document can be used for the radio systems and technologies mentioned above as well as other radio systems and technologies. The description below, however, describes an LTE system for example purposes, and LTE terminology is used throughout much of the description below, although the techniques are applicable beyond LTE applications.

[0057] Therefore, the following description provides examples, and is not limiting the scope, applicability or configuration set out in the claims. Changes can be made to the function and arrangement of the elements discussed without departing from the spirit and scope of the revelation. Various examples may omit, replace, or add various procedures or components as appropriate. For example, the methods described may be performed in a different order than described, and several steps may be added, omitted, or combined. Additionally, features described in connection with certain examples may be combined in other examples. The following description uses the terms DTX and discontinuous transmission interchangeably. Figure 1 illustrates an example of a wireless communications system 100 in accordance with various aspects of the present disclosure. The wireless communications system 100 includes base stations 105, communication devices, also known as a user equipment (UE) 115, and a core network 130. The base stations 105 can communicate with the UEs 115 under the control of a base station controller (not shown), which may be part of the core network 130 or the base stations 105 in various examples. The base stations 105 may communicate control information or user data with the main network 130 via return traffic links. In the examples, base stations 105 may communicate, either directly or indirectly, with each other via return traffic links 134, which may be wired or wireless communication links. The wireless communications system 100 may support operation on multiple carriers (waveform signals of different frequencies). The wireless communication links 125 can be modulated according to various radio technologies. Each modulated signal can carry control information (e.g. reference signals, control channels, etc.), overload information, data, etc. Wireless communication links 125 may also be established between UEs 115 in a configuration known as D2D communication.

[0058] The base stations 105 may communicate wirelessly with the UEs 115 via one or more base station antennas. Each of the base station locations 105 may provide communications coverage for a respective geographic area (e.g., coverage area) 110. In some examples, the base stations 105 may be referred to as a base transceiver station, a radio base station, , an access point, a radio transceiver, a basic service set (BSS), an extended service set (ESS), a NodeB, eNodeB (eNB), Home Node, a Home eNode, or some other suitable terminology. The coverage area 110 for a base station can be divided into sectors that make up a portion of the coverage area. The wireless communications system 100 may include base stations 105 of different types (e.g., macro, micro, or peak base stations). There may be overlapping coverage areas for different technologies.

[0059] The wireless communications system 100 may be a heterogeneous LTE/LTE-A network in which different types of base stations provide coverage for various geographic regions. For example, each base station 105 may provide communications coverage for a macrocell, a picocell, a femtocell, or other cell types. A macrocell typically covers a relatively large geographic area (e.g., several kilometers in radius) and can allow unrestricted access by UEs with service subscriptions with the network provider. A picocell would generally cover a relatively smaller geographic area and may allow unrestricted access by UEs with service subscriptions with the network provider. A femtocell would also generally cover a relatively small geographic area (e.g., a residence) and, in addition to unrestricted access, may also provide restricted access by UEs that have an association with the femtocell.

[0060] The core network 130 may communicate with the base stations 105 via a return traffic link 132 (e.g., SI, etc.). The base stations 105 may also communicate with each other (e.g., directly or indirectly) via return traffic links 134 (e.g., X2, etc.) or via return traffic links 132 (e.g., via main network 130). The wireless communications system 100 may support synchronous or asynchronous operation. For synchronous operation, base stations can have similar frame timing, and transmissions from different base stations can be approximately aligned in time. For asynchronous operation, base stations may have different frame timing, and transmissions from different base stations may not be time aligned. The techniques described in this document can be used for both synchronous and asynchronous operations.

[0061] The UEs 115 are dispersed throughout the wireless communications system 100, and each UE may be stationary or mobile. A UE 115 may communicate with other UEs 115 using D2D communications. One or more of a group of UEs (e.g., a first UE 115-a-1) utilizing D2D communications may be within a coverage area 110-a of a cell. Other UEs (e.g., a second UE 115-a-2 and a third UE 115-a-3) in such a group may be outside the cell's coverage area 110-a or otherwise without the ability to receive transmissions. of a base station 105. Groups of UEs 115-a communicating via D2D communications may utilize a one-to-many (1:M) system in which each UE 115-a transmits to all other UEs 115-a in the group. In some cases, a base station 105 facilitates resource scheduling for D2D communications. In other cases, D2D communications are performed independently of a base station 105. In some cases, UEs 115-a involved in D2D communications may be located relatively closer together. In other circumstances, UEs 115-a may communicate with each other over long distances. As mentioned above, in some examples a transmitting UE may transmit an SA that indicates when data will be transmitted and may indicate other characteristics of the data communication (e.g., MCS/RV, frequency hopping pattern, etc.). An SA may be retransmitted one or more times in accordance with an SA retransmission pattern, which may provide improved receipt of SAs. Furthermore, a receiving UE 115 may not monitor communications for an entire data transmission period, thereby reducing power consumption.

[0062] A UE 115 may also be called, by those skilled in the art, a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communications device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client , a client, or some other suitable terminology. A UE 115 may be a cellular telephone, a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a tablet-type computer, a laptop-type computer, a cordless telephone , a wireless local loop station (WLL), or the like. A UE 15 may have the ability to communicate with macro-eNBs, pico-eNBs, femto-eNBs, relays and the like.

[0063] The wireless communication links 125 shown in the wireless communication system 100 may include uplink (UL) transmissions from a UE 115 to a base station 105, or downlink (DL) transmissions from a base station 105 to a UE 115 via DL carriers. They can also represent D2D communication links. Downlink transmissions can also be called forward link transmissions while uplink transmissions can also be called reverse link transmissions.

[0064] Figure 2 illustrates an example 200 of SA resource groups and data resource groups for transmissions of SAs and data, in accordance with various aspects of the present disclosure. Specifically, Figure 2 illustrates a first group of SA resources 205-a and a first group of data resources 210-a, and a second group of SA resources 205-b and a second group of data resources 210-b. Resource groups 205 and 210 can be used to transmit SAs and data between UEs, such as UEs 115 in Figure 1, in D2D communications, for example. In some examples, a transmitting UE may transmit a first SA to one or more receiving UEs using SA1 resources 215 from within the SA resource group 205-a. The first SA may indicate capabilities (e.g., different timing or frequency capabilities) for subsequent data transmissions to the one or more receiving UEs or devices. In the example of Figure 2, the first SA may indicate resources D1 220, D2 225, and D3 230 from within the group of data resources 210-a that may be used to transmit data to a receiving UE. The content of the first SA may indicate one or more items of information related to data transmissions, as will be described in greater detail below. According to certain examples, the first SA may be retransmitted one or more times using other resources within SA1 resources 215. Retransmissions of the first SA may be performed in accordance with a predetermined retransmission pattern, such as retransmissions in certain times or frequencies.

[0065] Following the data resource group 210-a in this example is a second SA resource group 205-b, which can be used to transmit a second SA using SA2 resources 235. Similarly As with the first SA, the second SA may be retransmitted one or more times using other resources of SA2 235, and may indicate resources D4 240, D5 245, and D6 250 from within the data resource group 210-b which can be used to transmit data to a receiving UE. D2D transmissions from a transmitting UE may be transmitted as broadcast transmissions to one or more receiving UEs. According to some examples, a receiving UE may monitor the SA resource group 205-a and receive the first SA. If the first SA indicates that the receiving UE should receive data in a subsequent data transmission, the receiving UE may monitor the data resource group 210-a for the time(s) indicated by the first SA and may, thereby saving power by monitoring the data resource group Dl 220, D2 225 and D3 230. Similarly, if a receiving UE determines that the first SA, or any other SA transmitted in the SA resource group 205 -a, does not indicate that the receiving UE is scheduled to receive data in the data resource group 210-a, the receiving UE may discontinue monitoring D2D transmissions until the second SA resource group 205-b.

[0066] As mentioned above, an SA may be retransmitted one or more times within an SA resource group. Now, with reference to Figure 3A, an example of a frame structure 300 for SA retransmissions within an SA resource group 205-c is described. The SA resource group 205-c can be used, for example, in D2D communications between UEs, such as UEs 115 in Figure 1. In this example, the SA resource group 205-c is a resource group of 4 ms that includes four subframes 310, 315, 320, and 325. In some examples, the 4ms SA resource group 205-c may be followed by a 160ms data resource group (e.g., data resource group 210 in Figure 2).

[0067] According to certain examples, each subframe 310 to 325 may include two consecutive time windows, window 0 and window 1, and may be illustrated as a resource grid representing two time windows. The resource grid may be divided into multiple resource elements 330. In LTE, a resource block 335 may contain 12 consecutive subcarriers in the frequency domain and, for a normal cyclic prefix in each OFDM symbol, 7 consecutive OFDM symbols in the time domain, or 84 feature elements 330. Some of the feature elements 330 may include one or more reference signals. The number of bits carried by each resource element 330 may depend on the modulation scheme. Thus, the more resource blocks a UE receives and the larger the modulation scheme is, the higher the data rate can be for the UE. A downlink control channel such as a physical downlink control channel (PDCCH) can be time division multiplexed with a shared physical downlink channel (PDSCH).

[0068] In the example of Figure 3A, resource block 335 in subframe 310 may be used to transmit an SA transmission. The SA may then be retransmitted using resource block 340 of subframe 320, in some examples. SA retransmission can provide transmission diversity to transmit multiple versions of the same data over multiple channels. Each of the channels can be defined according to one or more partitions into a time domain (e.g. time windows), frequency domain (e.g. subcarriers), coding domain (e.g. CDMA coding), or antenna/direction (e.g. different antenna ports). Thus, using the example frame structure 300 of Figure 3A, transmission diversity can be achieved by transmitting different versions of the SA using different resource elements. In other examples, transmission diversity can also be achieved by transmitting different versions of the data using the same resource elements and different coding, antennas, or direction. In this way, a receiving UE that receives interference corresponding to certain resource elements in a subframe can monitor other resources for retransmissions of the SA, and can combine two or more of the received versions of the SA to estimate and cancel the interference.

[0069] According to various examples, the retransmission pattern for retransmitting SAs may include a number of retransmissions, and specific resources that are used for the retransmissions. For example, the retransmission pattern may be a fixed frequency hopping pattern, a fixed time pattern, or a combination thereof. Figure 3B illustrates another example of a frame structure 300-a for SA retransmissions within an SA resource group 205-d. The SA resource group 205-d, similar to that described with respect to Figure 3A, can be used in D2D communications between UEs, such as UEs 115 in Figure 1. In this example, the SA resource group 205-d is a 4 ms resource group that includes four subframes 310-a, 315-a, 320-a, and 325-a. In this example, a first resource block 335-a of subframe 310-a may be used for an SA transmission and a second resource block 340-a of subframe 320-a may be used for an SA retransmission. In this example, the second resource block 340-a uses different frequency resources and different time resources than the first resource block 335-a.

[0070] The specific retransmission pattern for the one or more SA retransmissions may be determined, for example, by a fixed frequency hopping pattern, fixed time pattern, or combination thereof, which is indicated in a block of information. system (SIB). In other examples, the relay standard may be a predefined standard that is established by a specification or wireless communications standard. In some examples, a number of different retransmission patterns may be available, and a specific retransmission pattern may be determined based on the first resource block 335 within the SA resource group 205. The retransmission pattern may identify, e.g. , miscellaneous time resources within the SA resource group 205 or miscellaneous frequency resources within the SA resource group 205.

[0071] A transmitting UE, such as a UE 115 of Figure 1, may, in some examples, receive a message to transmit the SA from a base station or eNB, such as an eNB 105 of Figure 1. The message may include , for example, a base station resource grant that indicates resources for use in D2D communications. Based on the grant, the transmitting UE may determine an SA resource group and a data resource group which may be, for example, 4 ms and 160 ms resource groups, respectively. The transmitting UE may then determine the first block of resources to transmit the SA based, at least in part, on the grant. In some examples, the message received by the transmitting UE may include downlink control information (DCI) comprising an index identifying the first resource block. The index may be included, for example, in a DCI resource block assignment field, where resource block assignments may be mapped to resource blocks for use in transmitting SAs. As noted above, resources for SA retransmissions can then be determined based on the block of resources for the initial SA transmission.

[0072] The SA may include, as mentioned above, information relating to one or more subsequent data transmissions in the data resource group, such as data resource groups 210 of Figure 2, for example. The SA may include, for example, a modulation and coding scheme (MCS) and a redundancy version (RV) for subsequent data transmission. Additionally, the SA may include a frequency hopping pattern for subsequent data transmissions, wherein a first data transmission may use first frequency resources, and a second data transmission may use multiple frequency resources of the first data transmission. . The SA may additionally or alternatively include a pattern of time jumps that indicated time resources that may be used for one or more data transmissions. In some examples, the SA may include a time offset that indicates a time for the first data transmission relative to the transmission of the SA. In some deployments, a data transmission may have a fixed offset (e.g., 4 ms) from the SA, and the time offset may establish a time for the data transmission that is in excess of the 4 ms base offset, e.g. example. In other examples, the SA may include a target identification (ID) for subsequent data transmission, the subsequent data transmission may be scrambled using the target ID. Such scrambling can provide interference mitigation for transmitted data, for example. In some examples, the SA transmission may include a cyclic redundancy check (CRC) scrambled by the target ID.

[0073] As mentioned above, an SA may include information that indicates details for one or more data transmissions in a group of data resources. Now, with reference to Figure 4A, example 400 of SA resource groups and data resource groups for transmissions of SAs and data in accordance with various aspects of the present disclosure are described. In this example, a first group of SA resources 205-e is followed by a first group of data resources 210-c, and a second group of SA resources 205-f is followed by a second group of data resources 210- d. SA resource groups 205 and data resource groups 210 may be examples of the SA or data resource groups of Figures 2, 3A, or 3B, and may be used, for example, in D2D communications between UEs, such as the UEs 115 in Figure 1. In this example, the SA resource groups 205-e and 205-f are 4 ms resource groups that are each followed by 160 ms data resource groups 210-c and 210- d, respectively.

[0074] In the example of Figure 4A, a first SA is transmitted using first SA resources 410. The first SA resources 410 may include resources for the first SA transmission as well as one or more SA retransmissions, as per discussed above, and may include information related to a first data transmission 420. The first SA may include, for example, information related to a time offset 430, and the first data transmission 420 may be transmitted following the time offset. 430. Similarly, a second SA may be transmitted using second SA resources 415. The second SA resources 415, as with the first SA resources 410, may include resources for the second SA transmission as well as a or more SA retransmissions, as discussed above, and may include information relating to a second data transmission 425. The second SA may include, for example, information relating to a second time offset 435, and the second data transmission 425 may be transmitted following the second time offset 435. The time offsets 430 and 435 may be the same time offset, or may be different time offsets. In some examples, as mentioned above, a specific time offset 430, 435 may be mapped to a specific resource in the SA resource group 205 that is used for the first transmission of an SA. In some implementations, data transmissions 420, 425 may have a fixed offset (e.g., 4 ms) from the first resource block of the respective SA resources 410, 415, and the respective time offsets 430, 435 may be set as displacements in excess of the base displacement of 4 ms. In addition, or alternatively, to a time shift such as time offsets 430, 435, an SA may include, in some examples, a modulation and coding scheme (MCS) or a redundancy version (RV) for subsequent transmission. of data. In other examples, an SA may include a field or indicator that indicates the transmitter's last SA transmission, which a receiving device may use to determine when to turn off receiving components, which may then be turned back on based on when a data is expected, or for a subsequent SA transmission period (for example, a subsequent SA 4 ms resource group).

[0075] In some examples, an SA may include a timing offset pattern for subsequent data transmissions. Figure 4B illustrates an example 400-a of timing patterns for data transmissions in groups of data resources, in accordance with various aspects of the present disclosure. In this example, SA resource group 205-g is followed by a data resource group 210-e, and a second SA resource group 205-h is followed by a second data resource group 210-f. SA resource groups 205 and data resource groups 210 may be examples of the SA or data resource groups of Figures 2, 3A, or 3B, and may be used, for example, in D2D communications between UEs, such as the UEs 115 in Figure 1. In this example, three data transmissions 440, 445, 450 are transmitted in the data resource group 210-e that follows an SA transmission 410-a. Similarly, a second set of three data transmissions 455, 460, 465 is transmitted in the data resource group 210-f that follows the second SA transmission 415-a. Data transmissions 440 to 465 may be transmitted, according to various examples, according to a timing pattern that is indicated in the respective SA transmission 410-a or 415-a. In some examples, the SA may include a timing offset and an indication of a number of data transmissions. For example, the SA may include the offset for the first data transmission relative to the SA transmission, which in one example is determined as SA [(n + 4) + m * X - SA], where n is the time of the resource used for the initial SA transmission, m is the offset size and X is the number of offsets.

[0076] In some examples, the SA may also include downlink control information. For example, the contents of an eNB DCI can simply be transmitted as they are in SA. In other examples, SAs may be sent in a fixed MCS and retransmission scheme, but contain within them a different MCS/RV for subsequent data transmissions. SAs may also contain, in certain examples, a target ID. Such a target ID may be compressed in some examples, such as when a target ID exceeds a certain size. The target ID sent in the SA can be used to scramble subsequent data transmissions. Such scrambling can provide interference mitigation for transmitted data, for example. The receiving UE, once the SA is received, may then determine resources from the data resource group 210-e and 210-f that must be monitored in connection with receiving the data transmissions. In some examples, a single data transmission may be repeated a number of times using different resources to improve the probability of proper receipt of data transmissions 440 to 465.

[0077] Furthermore, according to certain examples, the SA may include a frequency hopping pattern for subsequent data transmissions, wherein a first data transmission may use first frequency resources, and a second data transmission may use various frequency features of the first data transmission. Figure 4C illustrates an example 400-b of frequency hopping patterns for data transmissions in groups of data resources, in accordance with various aspects of the present disclosure. In this example, the SA resource group 205-i is followed by a data resource group 210-g, and a second SA resource group 205-j is followed by a second data resource group 210-h. SA resource groups 205 and data resource groups 210 may be examples of the SA or data resource groups of Figures 2, 3A, or 3B, and may be used, for example, in D2D communications between UEs, such as the UEs 115 in Figure 1. In this example, three data transmissions 470, 475, 480 are transmitted in the data resource group 210-g that follows an SA transmission 410-b. Similarly, a second set of three data transmissions 485, 490, 495 is transmitted in the data resource group 210-h that follows the second SA transmission 415-b. Data transmissions 440 to 465 may be transmitted, according to various examples, in accordance with frequency hopping and timing pattern that is indicated in the respective SA transmission 410-b or 415-b.

[0078] In some examples, the SA may include a frequency hopping pattern, a timing offset, and an indication of a number of data transmissions. In certain examples, for data transmissions 470, 475 and 480, the frequency hopping pattern, timing pattern or number of data transmissions may be determined based on the resource in the SA resource group 205-i used to transmit the first transmission of SA 410-b. Likewise, data transmissions 485, 490, and 495 may have timing, frequency hopping, and a number of transmissions based on the resource in the resource group of SA 205-j used to transmit the second transmission of SA 415-b . The receiving UE may then determine resources from the data resource group 210-e and 210-f that must be monitored in connection with receiving the data transmissions. In other examples, the SA may include a target identification (ID) for subsequent data transmission, the subsequent data transmission may be scrambled using the target ID. Such scrambling can provide interference mitigation for transmitted data, for example.

[0079] Figure 5 shows a block diagram 500 of a UE 115-b for transmitting or receiving SA and data transmissions in accordance with various aspects of the present disclosure. The UE 115-b may be an example of one or more aspects of a UE 115 described with reference to Figure 1. The UE 115-b may include a receiver 505, an SA management module 510, or a transmitter 515. The UE 115-b may also include a processor. Each of these components can be in communication with each other.

[0080] The components of the UE 115-b may, individually or collectively, be implemented with one or more Application Specific Integrated Circuits (ASICs) adapted to perform some or all of the applicable hardware functions. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits may be used (e.g., Structured/Platform ASICs, Field Programmable Gate Arrays (FPGAs), and other semi-custom ICs), which may be programmed in any manner known in the art. The functions of each unit can also be implemented, in whole or in part, with instructions embedded in a memory, formatted to be executed by one or more general or application-specific processors.

[0081] Receiver 505 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, etc.). For example, receiver 505 may receive a message from a base station that indicates one or more resources to be used for SA or data transmissions. The base station message can be received, for example, in a SIB or in a DCI, for example. Information may be forwarded to the SA management module 510, and to other components of the UE 115-b.

[0082] The SA management module 510 may determine scheduling assignments for one or more data transmissions. If the UE 115-b is a D2D transmission device, for example, the SA(s) can be determined to receive UEs, and resources from an SA resource group can be determined for the transmission of the SA(s). Additionally, the SA management module 510 may determine a retransmission pattern for retransmissions from the SA(s), which may include one or both of a timing pattern and frequency hopping pattern for SA retransmissions, from similarly as discussed above. If the UE 115-b is a D2D receiving device, the SA management module 510 can monitor SA resources and determine whether an SA transmission or retransmission is received. Based on resources from the SA resource group used for SA(s) transmissions, the SA management module 510 may determine an SA relay pattern and resources that should be used for data transmissions, which may include one or both of a timing pattern and frequency hopping pattern, in a similar manner as discussed above.

[0083] The transmitter 515 may transmit the one or more signals received from other components of the UE 115-b. For example, transmitter 515 may transmit SA and data transmissions to one or more receiving UEs in D2D transmissions. In some examples, the transmitter 515 may be co-located with the receiver 505 in a transceiver module. Transmitter 515 may include a single antenna, or it may include a plurality of antennas.

[0084] Figure 6 shows a block diagram 600 of a UE 115-c for transmitting or receiving SA and data transmissions in accordance with various aspects of the present disclosure. The UE 115-c may be an example of one or more aspects of a UE 115 described with reference to Figures 1 or 5. The UE 115-c may include a receiver 505-a, an SA management module 510-a, or a 515-a transmitter. The UE 115-c may also include a processor. Each of these components can be in communication with each other. The SA management module 510-a may also include an SA transmission module 605 and an SA relay module 610.

[0085] The components of the UE 115-c may, individually or collectively, be implemented with one or more Application Specific Integrated Circuits (ASICs) adapted to perform some or all of the applicable hardware functions. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits may be used (e.g., Structured/Platform ASICs, Field Programmable Gate Arrays (FPGAs), and other semi-custom ICs), which may be programmed in any manner known in the art. The functions of each unit can also be implemented, in whole or in part, with instructions embedded in a memory, formatted to be executed by one or more general or application-specific processors.

[0086] The receiver 505-a may receive information that may be forwarded to the SA management module 510-a, and to other components of the UE 115-c as described above with reference to Figure 5. The SA management module 510-a may be configured to perform the operations described above with reference to Figure 5. The transmitter 515-a may transmit the one or more signals received from other components of the UE 115-c. For example, in cases where the UE 115-c is a D2D transmitting device, it may transmit SA and data transmissions using D2D communications to one or more receiving UEs.

[0087] The SA transmission module 605 may be configured to determine SAs and resources from a group of SA resources for use in SA transmissions, in a similar manner as discussed above in relation to Figures 2, 3A, 3B, 4A , 4B or 4C. The SA retransmission module 610 may be configured to determine SA retransmission patterns, in a similar manner as discussed above in relation to Figures 2, 3A, 3B, 4A, 4B or 4C.

[0088] Figure 7 shows a block diagram 700 of a UE 115-d for transmitting or receiving SA and data transmissions in accordance with various aspects of the present disclosure. The UE 115-d may be an example of one or more aspects of a UE 115 described with reference to Figures 1, 5 or 6. The UE 115-d may include a receiver 505-b, an SA management module 510- b or a 515-b transmitter. The UE 115-d may also include a processor. Each of these components can be in communication with each other. The SA management module 510-b may also include a control information index module 705 and a displacement determination module 710.

[0089] The components of the UE 115-d may, individually or collectively, be implemented with one or more Application Specific Integrated Circuits (ASICs) adapted to perform some or all of the applicable hardware functions. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits may be used (e.g., Structured/Platform ASICs, Field Programmable Gate Arrays (FPGAs), and other semi-custom ICs), which may be programmed in any manner known in the art. The functions of each unit can also be implemented, in whole or in part, with instructions embedded in a memory, formatted to be executed by one or more general or application-specific processors.

[0090] The receiver 505-b, in this example, may receive information from a base station that indicates a group of SA resources that may be forwarded to the SA management module 510-b, and to other components of the UE 115-b. d. The SA management module 510-b may also be configured to perform the operations described above with reference to Figures 5 or 6. The transmitter 515-b may transmit the one or more signals received from other components of the UE 115-d. For example, in cases where the UE 115-d is a D2D transmitting device, it may transmit SA and data transmissions using D2D communications to one or more receiving UEs.

[0091] The control information index module 705 may be configured to receive a message from a base station that indicates a group of SA resources for use in SA transmissions and retransmissions, in a similar manner as discussed above in relation to Figures 2, 3 A, 3B, 4A, 4B or 4C. The message may be received, for example, in DCI received by the UE 115-d. In other examples, the message may be received in a SIB by UE 115-d. The offset determination module 710 may be configured to determine timing offsets for the transmission of SA transmissions and data in D2D communications, as described with respect to Figures 2, 3A, 3B, 4A, 4B, or 4C, by example.

[0092] Figure 8 shows a block diagram 800 of a UE 115-e for transmitting or receiving SA and data transmissions in accordance with various aspects of the present disclosure. The UE 115-e may be an example of one or more aspects of a UE 115 described with reference to Figures 1, 5, 6 or 7. The UE 115-e may include a receiver 505-c, an SA management module 510-c, or a 515-c transmitter. The UE 115-e may also include a processor. Each of these components can be in communication with each other. The SA management module 510-c may also include an MCS/RV determination module 805, a frequency hopping determination module 810, an offset and timing determination module 815, and a target ID module 820.

[0093] The components of the UE 115-e may, individually or collectively, be implemented with one or more Application Specific Integrated Circuits (ASICs) adapted to perform some or all of the applicable hardware functions. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits may be used (e.g., Structured/Platform ASICs, Field Programmable Gate Arrays (FPGAs), and other semi-custom ICs), which may be programmed in any manner known in the art. The functions of each unit can also be implemented, in whole or in part, with instructions embedded in a memory, formatted to be executed by one or more general or application-specific processors.

[0094] The receiver 505-c can receive information that can be forwarded to the SA management module 510-c, and to other components of the UE 115-e as described above with reference to Figures 5, 6 or 7. The module SA management system 510-c can be configured to perform the operations described above with reference to Figures 5, 6 or 7. The transmitter 515-c can transmit the one or more signals received from other components of the UE 115-e. For example, in cases where the UE 115-e is a D2D transmitting device, it may transmit SA and data transmissions using D2D communications to one or more receiving UEs.

[0095] The MCS/RV determination module 805 may be configured to determine MCS/RV for subsequent data transmissions that follow an SA transmission, in a similar manner as discussed above in relation to Figure 4B, for example. The frequency hopping determination module 810 may be configured to determine SA retransmission frequency hopping patterns in a similar manner as discussed above in relation to Figures 2, 3A, 3B, 4A, 4B or 4C. The offset and timing determination module 815 may be configured to determine SA transmission, SA retransmission, and data transmission timing in a similar manner as discussed above in connection with Figures 2, 3A, 3B, 4A, 4B, or 4C. The target ID module 820 may be configured to determine a target ID, compress the target ID if necessary, and scramble data transmissions based on the target ID, in a similar manner as discussed above in connection with Figures 2, 3A, 3B. 4A, 4B or 4C. The target ID module 820 may also be configured to decode scrambled data transmissions received in the UE 115-e based on information received in an SA, in a similar manner as discussed above.

[0096] Figure 9 shows a diagram of a system 900 for transmitting or receiving SA transmissions and data in accordance with various aspects of the present disclosure. System 900 may include a UE 115-f, which may be an example of a UE 115 with reference to Figures 1, 5, 6, 7 or 8. The UE 115-f may generally include components for two-way voice and data communications. which include components for transmitting communications and components for receiving communications.

[0097] The UE 115-f may include antenna(s) 940, a transceiver module 935, a processor module 905, and memory 915 (including software (SW) 920), which each may communicate, directly or indirectly, a with each other (e.g., via one or more 945 buses). The transceiver module 935 may be configured to communicate bidirectionally, through the antenna(s) 940 or one or more wired or wireless links, with one or more networks, as described above. For example, transceiver module 935 may be configured to communicate bidirectionally with a base station 105. Transceiver module 935 may include a modem configured to modulate packets and deliver the modulated packets to the antenna(s). ) 940 for transmission, and to demodulate packets received from the antenna(s) 940. Although the UE 115-f may include a single antenna 940, the UE 115-f may also have multiple antennas 940 capable of transmitting or receiving ,simultaneously, multiple wireless transmissions. The transceiver module 935 may also have the ability to communicate simultaneously with one or more base stations 105.

[0098] Memory 915 may include Random Access Memory (RAM) and Read-Only Memory (ROM). Memory 915 may store executable and computer-readable software/firmware code 920 that contains instructions that are configured so that, when executed, they cause processor module 905 to perform various functions described herein (e.g., call processing , database management, carrier mode indicator processing, reporting CSI, etc.). Alternatively, software/firmware code 920 may not be directly executable by processor module 905 but be configured to cause a computer (e.g., when compiled and executed) to perform functions described herein. The processor module 905 may include an intelligent hardware device, e.g., a central processing unit (CPU), a microcontroller, an Application Specific Integrated Circuit (ASIC), etc. may include Random Access Memory (RAM) and Read-Only Memory (ROM).

[0099] Memory 915 may store executable and computer-readable software/firmware code 920 that contains instructions that are configured so that, when executed, they cause processor module 905 to perform various functions described herein (e.g., call processing, database management, carrier mode indicator processing, reporting CSI, etc.). Alternatively, software/firmware code 920 may not be directly executable by processor module 905 but be configured to cause a computer (e.g., when compiled and executed) to perform functions described herein. The processor module 905 may include an intelligent hardware device (e.g., a central processing unit (CPU), a microcontroller, an Application Specific Integrated Circuit (ASIC), etc.). The base station communications module 925 may perform operations related to communications with one or more base stations.

[0100] The SA management module 910 may be configured to determine scheduling assignments for one or more data transmissions and perform operations related to SA and data transmissions as discussed above with respect to Figures 2, 3A, 3B, 4A, 4B, 4C, 5, 6, 7 or 8. If the UE 115-f is a D2D transmission device, for example, the SA(s) may be determined to receive UEs, and resources from an SA resource group can be determined for transmission of the SA(s). Additionally, the SA management module 910 may determine a retransmission pattern for retransmissions from the SA(s), which may include one or both of a timing pattern and a frequency hopping pattern for SA retransmissions, from similarly as discussed above. If the UE 115-f is a D2D receiving device, the SA management module 910 can monitor SA resources and determine whether an SA transmission or retransmission is received. Based on the resources from the SA resource group used for SA(s) transmissions, the SA management module 910 may determine an SA retransmission pattern and resources that should be used for data transmissions, which may include one or both of a timing pattern and frequency hopping pattern, in a similar manner as discussed above.

[0101] Figure 10 shows a block diagram of a communications system 1000 that can be configured for use in receiving and transmitting D2D communications, in accordance with various aspects of the present disclosure. The communications system 1000 may be an example of aspects of the wireless communications systems 100, or 900 depicted in Figures 1 or 9, respectively. The communications system 1000 may include a base station 105-c. Base station 105-c may include base station antenna(s) 1045, a base station transceiver module 1050, base station memory 1080, and a base station processor module 1070, each of which may be in communication, either direct or indirectly, with each other (for example, through one or more buses). The base station transceiver module 1050 may be configured to communicate bidirectionally, via the base station antenna(s) 1045, with a UE 115-g, which may be an example of a UE 115 of Figures 1 , 5, 6, 7, 8, or 9. The base station transceiver module 1050 (or other components of the base station 105-c) may also be configured to communicate bidirectionally with one or more networks. In some cases, the base station 105-c may communicate with the main network 130-a or controller 1020 via the network communications module 1075. The base station 105-c may be an example of the base stations 105 of Figures 1 or 9. The controller 1020 may be integrated into the base station 105-c in some cases, such as with an eNodeB base station.

[0102] The base station 105-c can also communicate with other base stations 105, such as the base station 105-m and the base station 105-n. Each of the base stations 105 can communicate with the user device 115-g using different wireless communications technologies, such as different Radio Access Technologies. In some cases, the base station 105-c may communicate with other base stations such as 105-m or 105-n that utilize the base station communication module 1065. In some examples, the base station communication module 1065 may provide an The.

[0103] Base station memory 1080 may include Random Access Memory (RAM) and Read-Only Memory (ROM). The base station memory 1080 may also store executable and computer-readable software code 1085 that contains instructions that are configured so that, when executed, they cause the base station processor module 1070 to perform various functions described herein (e.g. example, receiving and transmitting D2D communications, and providing resource grants, timing information, and offset information for D2D communications). Alternatively, the software code 1085 may not be directly executable by the base station processor module 1070 but be configured to cause the computer, for example, when compiled and executed, to perform the functions described herein. The base station processor module 1070 may include an intelligent hardware device (e.g., a central processing unit (CPU), a microcontroller, an Application Specific Integrated Circuit (ASIC), etc.).

[0104] The base station transceiver module 1050 may include a modem configured to modulate packets and provide the modulated packets to the base station antenna(s) 1045 for transmission and to demodulate packets received from the antenna(s). s) of base station 1045. Although some examples of base station 105-c may include a single base station antenna 1045, base station 105-c may include multiple base station antennas 1045 for multiple links that may support carrier aggregation. For example, one or more links may be used to support macrocommunications with the user device 115-g.

[0105] In accordance with the architecture of Figure 10, the base station 105-c may additionally include a management communications module 1060. The management communications module 1060 may manage communications with other base stations 105. As an example, the management communications module 1060 may facilitate the transmission of D2D information, such as grants for D2D transmission devices, etc., as discussed above. By way of example, the management communications module 1060 may be a component of the base station 105-c communicating with some or all of the other components of the base station 105-c via a bus. Alternatively, the functionality of the management communications module 1060 may be implemented as a component of the base station transceiver module 1050, as a computer-readable medium, or as one or more controller elements of the base station processor module 1070.

[0106] Base station components 105-c may be configured to implement aspects discussed above in relation to Figures 2, 3A, 3B, 4A, 4B, 4C, 5, 6, 7, 8 or 9, which are not to be repeated here for the sake of brevity. For example, base station 105-d may include a base station D2D module 1067. Base station D2D module 1067 may include a D2D SA resource group module 1070 and D2D resource management module 1075 , which may be configured to perform or control any or all of the base station-related features or functions described with reference to Figures 1, 2, 3A, 3B, 4A, 4B, 4C, 5, 6, 7, 8 or 9. base station D2D module 1067, or portions thereof, may include a processor, or some or all of the functions of the base station D2D module 1067 may be performed by the base station processor module 1070 or in connection with the base station D2D module 1067. base station processor 1070. Additionally, the base station D2D module 1067, or portions thereof, may include a memory, or some or all of the functions of the base station D2D module 1067 may use base station memory 1080 or be used in connection with the base station memory 1080.

[0107] Figure 11 shows a flowchart 1100 that illustrates a method for SA transmission and retransmissions in accordance with various aspects of the present disclosure. Flowchart functions 1100 may be implemented by a transmission device, such as a UE 115 or components thereof as described with reference to Figures 1, 5, 6, 7, 8, 9 or 10. In some examples, a device, such as one of the UEs 115, may execute one or more sets of codes to control the functional elements of the device to perform the functions described below.

[0108] In block 1105, an SA is transmitted to one or more devices, wherein the SA indicates resources for a subsequent transmission of data to the one or more devices. For example, a transmitting UE may transmit an SA in a broadcast D2D transmission to one or more receiving UEs. In block 1110, the SA is retransmitted according to a predetermined retransmission pattern. The predefined retransmission pattern can be a time-based repeat pattern for a number or retransmissions (for example, three retransmissions every 4 ms that follow the immediate previous transmission). The predefined retransmission pattern can also be a frequency hopping pattern, where one or more retransmissions use different frequency resources. Such retransmissions can improve the probability of successful receipt of the SA at the receiving device.

[0109] It should be noted that the flowchart method 1100 is only one implementation and that the method operations and steps may be arranged or otherwise modified in such a way that other implementations are possible.

[0110] Figure 12 shows a flowchart 1200 that illustrates a method for SA transmission and retransmissions in accordance with various aspects of the present disclosure. Flowchart functions 1200 may be implemented by a transmission device, such as a UE 115 or components thereof as described with reference to Figures 1, 5, 6, 7, 8, 9 or 10. In some examples, a device, such as one of the UEs 115, may execute one or more sets of codes to control the functional elements of the device to perform the functions described below.

[0111] In block 1205, a first block of resources within an SA resource group for transmitting an SA is determined. In block 1210, the SA is transmitted to the one or more devices, wherein the SA indicates resources for a subsequent transmission of data to the one or more devices. At block 1215, the SA is retransmitted according to a predetermined retransmission pattern that is based, at least in part, on the first resource block. In this way, different predefined retransmission patterns can be associated with different resource blocks within the SA resource group. Such patterns can be transmitted, for example, in a SIB or can be defined in a standard, to name two exemplary options for defining retransmission standards. Such retransmissions can improve the probability of successful receipt of the SA at the receiving device.

[0112] It should be noted that the flowchart method 1200 is only one implementation and that the method operations and steps may be arranged or otherwise modified in such a way that other implementations are possible.

[0113] Figure 13 shows a flowchart 1300 that illustrates a method for SA transmission and retransmissions in accordance with various aspects of the present disclosure. Flowchart functions 1300 may be implemented by a receiving device, such as a UE 115 or components thereof as described with reference to Figures 1, 5, 6, 7, 8, 9 or 10. In some examples, a device, such as one of the UEs 115, may execute one or more sets of codes to control the functional elements of the device to perform the functions described below.

[0114] In block 1305, an SA transmission is received, wherein the SA indicates resources to receive a subsequent data transmission. In block 1310, at least one retransmission of the SA is received according to a predetermined retransmission pattern. The predefined retransmission pattern can be a time-based repeat pattern for a number or retransmissions (for example, three retransmissions every 4 ms that follow the immediate previous transmission). The predefined retransmission pattern can also be a frequency hopping pattern, where one or more retransmissions use different frequency resources. Such retransmissions can improve the probability of successful receipt of the SA.

[0115] It should be noted that the flowchart method 1300 is only one implementation and that the method operations and steps may be arranged or otherwise modified in such a way that other implementations are possible.

[0116] Figure 14 shows a flowchart 1400 that illustrates a method for SA transmission and retransmissions in accordance with various aspects of the present disclosure. Flowchart functions 1400 may be implemented by a transmission device, such as a UE 115 or components thereof as described with reference to Figures 1, 5, 6, 7, 8, 9 or 10. In some examples, a device, such as one of the UEs 115, may execute one or more sets of codes to control the functional elements of the device to perform the functions described below.

[0117] In block 1405, a message is received from a base station. The message may be received in, for example, a DCI or SIB transmission. In block 1410, a group of SA resources is determined based, at least in part, on the message. For example, a SIB can provide an indication of resources that should be used for SA transmissions and retransmissions. Such a SIB may also indicate capabilities for data transmission. At block 1415, a first resource block within the SA resource group is identified, wherein the first resource block is used to transmit an SA to one or more receivers. In some examples, different predefined retransmission patterns may be associated with different resource blocks within the SA resource group.

[0118] It should be noted that the flowchart method 1400 is only one implementation and that the method operations and steps may be arranged or otherwise modified in such a way that other implementations are possible.

[0119] The detailed description set forth above in connection with the attached drawings describes exemplary examples and does not represent only those examples that can be implemented or that are within the scope of the claims. The term "exemplary" used throughout this description means "serving as an example, occurrence, or illustration," not "preferred" or "advantaged over other examples." The detailed description includes specific details for the purpose of providing an understanding of the set of procedures described. This set of procedures, however, can be practiced without these specific details. In some examples, known structures and devices are shown in block diagram form in order to avoid obscuring concepts in the examples described.

[0120] Information and signals can be represented using any of a variety of different technologies and sets of procedures. For example, data, instructions, commands, information, signals, bits, symbols, and integrated circuits that may be referenced throughout the above description may be represented by voltages, electrical currents, electromagnetic waves, magnetic particles or fields, optical particles or fields or any combination thereof.

[0121] The various illustrative blocks and modules described together in connection with the disclosure herein may be implemented or realized with 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, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but alternatively, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be deployed as a combination of computing devices, for example, 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.

[0122] The functions described in this document can be implemented in hardware, software, firmware, or any combination thereof. If implemented in software running through a processor, functions can be stored, or transmitted, as one or more instructions or code in a computer-readable medium. Other examples and implementations are within the scope and spirit of the disclosure and appended claims. For example, due to the nature of software, the functions described above may be implemented using software running through a processor, hardware, firmware, wired connection, or combinations of any of these. Resource deployment functions may also be physically located in various positions that include distribution thereof, such that portions of the functions are deployed in different physical locations. Additionally, as used herein, including in the claims, "or" as used in a list of items (e.g., a list of items preceded by a phrase such as "at least one of" or "one or more of" ), indicates a disjunctive list such that, for example, a list of "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 ).

[0123] Computer readable media includes both the computer storage medium and the communication medium which includes any medium that can be enabled to transfer a computer program from one location to another. A storage medium can be any available medium that can be accessed by a general-purpose or specific-purpose computer. By way of example, and without limitation, a computer-readable medium or processor-readable medium may comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to load or store desired program code in the form of instructions or data structures and that can be accessed by a computer or processor. Furthermore, any connection can properly be called a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscription line (DSL), or wireless technologies such as infrared, radio and microwave, then coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Magnetic disc and optical disc, as used herein, include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk, and Blu-ray disc, where magnetic discs often reproduce data in a magnetic, while optical discs reproduce data optically with lasers. Combinations of the foregoing are also included within the scope of computer-readable media.

[0124] The foregoing description of the disclosed embodiments is provided to enable any individual skilled in the art to produce or use the present invention. Various modifications in such embodiments will be immediately apparent to those skilled in the art and the generic principles defined herein may be applied to other variations without departing from the spirit or scope of the disclosure. Throughout this disclosure, the terms "example" or "exemplary" indicate an example or an occurrence and do not imply or require any preference for the observed example. Accordingly, the present disclosure is not intended to be limited to the embodiments shown in this document, but is intended to be compatible with the broadest scope consistent with the particulars and innovative principles disclosed in this document.

Claims (15)

1. Method (1200) of wireless communications characterized by the fact that it comprises: determining (1205) a first block of resources within a group of scheduling assignment resources, SA, to transmit an SA, wherein the SA indicates resources for data transmissions to be sent in a data resource group that follows the SA resource group; transmitting (1210) the SA to one or more devices using the first resource block; and retransmitting (1215) the SA using a second resource block within the SA resource group in accordance with a predetermined retransmission pattern, wherein the predetermined retransmission pattern specifies the use of different frequency or time resources to retransmit the SA based, at least in part, on the first block of resources. 2. Method according to claim 1, characterized by the fact that the SA is transmitted in a device-to-device broadcast transmission, D2D. 3. Method according to claim 1, characterized by the fact that the retransmission pattern comprises a fixed frequency hopping pattern, a fixed time pattern or a combination thereof, wherein the fixed frequency hopping pattern, fixed time pattern or combination thereof is indicated in a system information block, SIB, or is a predefined pattern. 4. Method, according to claim 1, characterized by the fact that the retransmission pattern identifies one or more of: diverse time resources within the SA resource group; or miscellaneous frequency resources within the SA resource group. 5. The method of claim 1, wherein the SA resource group comprises a plurality of Long Term Evolution, LTE subframes. 6. The method of claim 1, further comprising: receiving a grant to transmit the SA from a base station. 7. The method of claim 6, wherein transmitting the SA comprises: determining the first block of resources to transmit the SA based, at least in part, on the grant, and wherein the grant comprises information from downlink control, DCI, which comprise an index that identifies the first resource block within the SA resource group in which the index is included in a resource block assignment field of the DCI. 8. Method, according to claim 1, characterized by the fact that the SA comprises one or more of: a modulation and coding scheme, MCS, and a redundancy version, RV, for data transmissions, a frequency hopping for the data transmissions, an identification, ID, target for the data transmissions, and wherein the data transmissions are scrambled using the target ID; an offset for a first data transmission relative to the SA transmission; a cyclic redundancy check, CRC, scrambled by an identification, ID, target and an indicator of a last SA transmission. 9. Apparatus for wireless communications, characterized in that it comprises: means for determining a first block of resources within a group of scheduling assignment resources, SA, to transmit an SA, wherein the SA indicates resources for which transmissions data is sent in a data resource group that follows the SA resource group; means for transmitting the SA to one or more devices using the first resource block; and means for retransmitting the SA using a second block of resources within the SA resource group in accordance with a predetermined retransmission pattern, wherein the predetermined retransmission pattern specifies the use of different frequency or time resources to retransmit the SA based, at least in part, on the first block of resources. 10. A wireless communications method comprising: receiving (1305) a scheduling assignment transmission, SA, comprising an SA; determine a first resource block within an SA resource group where the SA transmission is received, the SA indicative resources for receiving data transmission to be sent in a data resource group that follows the SA resource group ; and receiving (1310) at least one retransmission of the SA in a second resource block within the SA resource group in accordance with a predetermined retransmission pattern, wherein the predetermined retransmission pattern specifies the use of different frequency or time resources to retransmit the SA based, at least in part, on the first resource block. 11. Method according to claim 10, characterized by the fact that it further comprises: combining the transmission and retransmission(s) of SA to determine the SA. 12. The method of claim 10, wherein the predetermined retransmission pattern comprises a fixed frequency hopping pattern, a fixed time pattern, or a combination thereof. 13. Method according to claim 12, characterized by the fact that the fixed frequency hopping pattern, the fixed time pattern or combination thereof is indicated in a system information block, SIB, received from a transmission device or is a predefined pattern. 14. The method of claim 10, wherein the SA comprises an offset to a first data transmission with respect to the SA resource group or the SA transmission. 15. An apparatus for wireless communications characterized by the fact that it comprises: means for receiving a scheduling assignment transmission, SA, comprising an SA; means for determining a first block of resources within an SA resource group where the SA transmission is received, the SA indicative resources for receiving data transmissions to be sent in an SA resource group that follows the resource group from SA; and means for receiving at least one retransmission of the SA on a second resource block within the SA resource group in accordance with a predetermined retransmission pattern, wherein the predetermined retransmission pattern specifies the use of different frequency or time resources for SA retransmission based, at least in part, on the first block of resources.