WO2014110804A1

WO2014110804A1 - Enhanced broadcast channel for low cost machine type communication with coverage enhancement

Info

Publication number: WO2014110804A1
Application number: PCT/CN2013/070707
Authority: WO
Inventors: Erlin Zeng; Wei Bai; Chunyan Gao; Na WEI; Shuang TAN; Haiming Wang
Original assignee: Broadcom Corporation
Priority date: 2013-01-18
Filing date: 2013-01-18
Publication date: 2014-07-24

Abstract

A process, apparatus, and computer program product for enhancing coverage enhancement for network node signals targeted to machine type communication (MTC) devices such as automated wireless meters for water, electric and gas usage measurement. Two enhanced master information block (MIB) formats are defined. A first format contains all critical system information for common user equipment (UE) while the second format contains the critical system information plus the system information specific to MTC users. The second format provides sufficient system information necessary for MTC user equipment to initialize random access channel procedure. UE determines the eMIB format based on the detected primary synchronization signal/secondary synchronization signal (PSS/SSS) scheme and decodes the eMIB accordingly.

Description

ENHANCED BROADCAST CHANNEL FOR LOW COST

MACHINE TYPE COMMUNICATION WITH COVERAGE ENHANCEMENT

TECHNOLOGICAL FIELD

The various embodiments relate to the field of wireless mobile network communications, and particularly to channel control and quality protocols in such networks.

BACKGROUND

An effort to improve system coverage in wireless networks is anticipated with a target of a 20dB improvement in coverage compared to defined Long Term Evolution (LTE) cell coverage for normal LTE user equipment (UE). The 20 dB coverage improvement should target low cost machine type communication (MTC) UEs using very low rate traffic with relaxed latency (e.g. size of the order of 100 bytes/message in uplink (UL) and 20 bytes/message in downlink (DL), and allowing latency of up to 10 seconds for DL and up to 1 hour in UL, which excludes voice communication). The coverage enhancement is intended to improve communication with machines such as industrial meters (e.g., electric, water, gas) often located deep within buildings.

For a 20dB improvement target for the worst channel, all of the DL/UL channels have to be enhanced, including shared channel (SCH), broadcast channel (BCH) and physical downlink control channel (PDCCH). Methods for each channel enhancement to get coverage improvement have been considered. Repetition had been considered as one potential solution.

The primary broadcast channel (PBCH) needs to support coverage enhancement since low cost MTC users need to acquire the necessary system information. Once the user equipment (UE) is synchronized to a cell and has obtained its physical layer identity, the UE needs to acquire system information broadcasted by the cell. The critical master information block (MIB) is transmitted on PBCH with a 40-ms transmission time interval (TTI) every 40 ms. The PBCH is mapped to four symbols in each frame on the 72 center subcarriers. Decoding delay can be traded for coverage by accumulating several TTIs coherently. The PBCH can also be power boosted for better coverage. Another possibility is to increase the resources allocated to PBCH.

BRIEF SUMMARY

A first embodiment is a method comprising causing one of at least first and second predefined enhanced master information block (eMIB) formats to be sent; and selecting a transmission scheme suited to the one of the eMIB formats being sent. The method may further comprise switching between the at least first and second eMIB formats according to whether receiving devices require coverage enhancement, and causing system information not signaled in the at least first and second eMIB formats to be sent via common search space of the physical control channel (PDCCH) with the system information-radio network temporary identifier (SI-RNTI). It is a method wherein the first eMIB format contains all critical system information for all normal UEs, and the second eMIB format contains all critical system information for normal UEs plus system information specific to machine type communication (MTC) UEs.

In one embodiment, the selected transmission scheme for the first eMIB format is the standard MIB information sent according to the physical broadcast channel (PBCH) scheme, and the selected transmission scheme for the second eMIB format is targeted to MTC UEs and employs primary synchronization signal/secondary synchronization signal (PSS/SSS) repetition and/or power boosting. In the method the choice between said first and second eMIB formats may be determined by the existence of MTC users with a coverage enhancement requirement, and the choice between said first and second eMIB formats may be based on a predefined time period such as a predefined quiet time period.

A related method comprises causing a primary synchronization signal/secondary synchronization signal (PSS/SSS) transmission scheme to be received and detected; and causing an enhanced master information block (eMIB) format to be decoded. This method further comprises determining if the PSS/SSS transmission scheme uses extra repetitions, and in the instance that PSS/SSS is received without extra repetitions, determining that a first eMIB format is received, and in the instance that PSS/SSS is received with extra repetitions, determining that a second eMIB format is received. In this embodiment, the first eMIB format is targeted to and contains all critical system information for all normal UEs, while the second eMIB format is targeted to and contains all critical system information for low cost machine type communication (MTC) UEs.

Another embodiment is an apparatus comprising at least a processor, a memory in communicating relation with the processor and having stored computer coded instructions within it, said instructions when executed by the processor causing the apparatus to perform: causing one of at least first and second predefined enhanced master information block (eMIB) formats to be sent, and selecting a transmission scheme suited to the one of the eMIB formats being sent. The apparatus may further comprise instructions causing the apparatus to perform switching between the at least first and second eMIB formats according to whether receiving devices require coverage enhancement, and causing system information not signaled in the at least first and second eMIB formats to be sent via common search space of the physical control channel (PDCCH) with the system information-radio network temporary identifier (SI-RNTI). In one embodiment, the first eMIB format contains all critical system information for all normal UEs, while the second eMIB format contains all critical system information for normal UEs plus system information specific to machine type communication (MTC) UEs. In the apparatus the selected transmission scheme for the first eMIB format may be the standard MIB information sent according to the physical broadcast channel (PBCH) scheme, and the selected transmission scheme for the second eMIB format may be targeted to MTC UEs and employs primary synchronization signal/secondary synchronization signal (PSS/SSS) repetition and/or power boosting. The selection between said first and second eMIB formats may be determined by the existence of MTC users with a coverage enhancement requirement, while the selection between said first and second eMIB formats may be based on a predefined time period such as a predefined quiet time period. This apparatus may be an enhanced node B, a network access point, or a base station.

In a related apparatus embodiment is a memory in communicating relation with the processor and having stored computer coded instructions within it, said instructions when executed by the processor causing the apparatus to perform: causing a primary synchronization signal/secondary synchronization signal (PSS/SSS) transmission scheme to be received and detected, and causing an enhanced master information block (eMIB) format to be decoded. Further instructions may cause the apparatus to perform determining if the PSS/SSS transmission scheme uses extra repetitions, and in the instance that PSS/SSS is received without extra repetitions, determining that a first eMIB format is received, or in the instance that PSS/SSS is received with extra repetitions, determining that a second eMIB format is received. In one embodiment, the first eMIB format is targeted to and contains all critical system information for all normal UEs, and the second eMIB format is targeted to and contains all critical system information for machine type communication (MTC) UEs. This apparatus may be a mobile phone, or a machine type communication device.

Another embodiment may be a computer program product comprising a non- transitory computer readable medium having stored computer coded instructions, said instructions when executed by a processor causing an apparatus to perform causing one of at least first and second predefined enhanced master information block (eMIB) formats to be sent; and selecting a transmission scheme suited to the one of the eMIB formats being sent. The instructions may further comprise switching between the at least first and second eMIB formats according to whether receiving devices require coverage enhancement, and causing system information not signaled in the at least first and second eMIB formats to be sent via common search space of the physical control channel (PDCCH) with the system information-radio network temporary identifier (SI-RNTI). In the program product instructions the first eMIB format contains all critical system information for all normal UEs, and the second eMIB format may contain all critical system information for normal UEs plus system information specific to machine type communication (MTC) UEs. In further instructions the selected transmission scheme for the first eMIB format may be the standard MIB information sent according to the physical broadcast channel (PBCH) scheme, and the selected transmission scheme for the second eMIB format may be targeted to MTC UEs and employs primary synchronization signal/secondary synchronization signal (PSS/SSS) repetition and/or power boosting. The selection between said first and second eMIB formats may be determined by the existence of MTC users with a coverage enhancement requirement, or the selection between said first and second eMIB formats may be based on a predefined time period such as a predefined quiet time period.

Another computer program product comprises a non-transitory computer readable medium having stored computer coded instructions, said instructions when executed by a processor causing an apparatus to perform: causing a primary synchronization signal/secondary synchronization signal (PSS/SSS) transmission scheme to be received and detected, and causing an enhanced master information block (eMIB) format to be decoded. This computer program product may further comprise instructions that cause an apparatus to perform: determining if the PSS/SSS transmission scheme uses extra repetitions, and in the instance that PSS/SSS is received without extra repetitions, determining that a first eMIB format is received, or in the instance that PSS/SSS is received with extra repetitions, determining that a second eMIB format is received. In this computer program product the first eMIB format may be targeted to and contains all critical system information for all normal UEs, and the second eMIB format may be targeted to and contains all critical system information for low cost machine type communication (MTC) UEs.

In another embodiment, an apparatus is provided comprising means for causing one of at least first and second predefined enhanced master information block (eMIB) formats to be sent; and means for selecting a transmission scheme suited to the one of the eMIB formats being sent. The apparatus may further comprise means for switching between the at least first and second eMIB formats according to whether receiving devices require coverage enhancement, and means for causing system information not signaled in the at least first and second eMIB formats to be sent via common search space of the physical control channel (PDCCH) with the system information-radio network temporary identifier (SI-RNTI). In this embodiment the first eMIB format contains all critical system information for all normal UEs, and the second eMIB format contains all critical system information for normal UEs plus system information specific to machine type communication (MTC) UEs. In the apparatus the selected transmission scheme for the first eMIB format may be the standard MIB information sent according to the physical broadcast channel (PBCH) scheme, and the selected transmission scheme for the second eMIB format may be targeted to MTC UEs and employs primary synchronization signal/secondary synchronization signal (PSS/SSS) repetition and/or power boosting. And in this apparatus the selection between said first and second eMIB formats may be determined by the existence of MTC users with a coverage enhancement requirement, and the selection between said first and second eMIB formats may be based on a predefined time period such as a predefined quiet time period.

A related apparatus may comprise means for causing a primary synchronization signal/secondary synchronization signal (PSS/SSS) transmission scheme to be received and detected, and means for causing an enhanced master information block (eMIB) format to be decoded. The apparatus may also comprise means for determining if the PSS/SSS transmission scheme uses extra repetitions, and in the instance that PSS/SSS is received without extra repetitions, means for determining that a first eMIB format is received, or in the instance that PSS/SSS is received with extra repetitions, means for determining that a second eMIB format is received. In this apparatus the first eMIB format may be targeted to and contains all critical system information for all normal UEs, and the second eMIB format may be targeted to and contains all critical system information for machine type communication (MTC) UEs.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Having thus described example embodiments of the invention in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:

Fig. 1 is a schematic drawing of a generalized wireless communications network. Fig. 2 is a schematic block drawing of an apparatus that may be embodied by a mobile terminal or an access point and may be specifically configured in accordance with an example embodiment of the present invention.

Fig. 3 is a flow diagram of a first embodiment of a method as described herein. Fig. 4 is a flow diagram of a second embodiment of a method as described herein. DETAILED DESCRIPTION

Various embodiments now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the inventions are shown. Indeed, these inventions may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.

As used in this application, the term "circuitry" refers to all of the following: (a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and (b) to combinations of circuits and software (and/or firmware), such as (as applicable): (i) to a combination of processor(s) or (ii) to portions of processor(s)/software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and (c) to circuits, such as a microprocessor(s) or a portion of a microprocessor(s), that require software or firmware for operation, even if the software or firmware is not physically present.

This definition of "circuitry" applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term "circuitry" would also cover an implementation of merely a processor (or multiple processors) or portion of a processor and its (or their) accompanying software and/or firmware. The term "circuitry" would also cover, for example and if applicable to the particular claim element, a baseband integrated circuit or application specific integrated circuit for a mobile phone or a similar integrated circuit in server, a cellular network device, or other network device.

Although the method, apparatus and computer program product of example embodiments of the present invention may be implemented in a variety of different systems, one example of such a system is shown in Fig. 1, which includes a mobile terminal 8 that is capable of communication with a network 6 (e.g., a core network) via, for example, an access point 2 (AP). While the network may be configured in accordance with Global System for Mobile communications (GSM) / Enhanced Data rates for Global Evolution (EDGE) Radio Access Network (GERAN), the network may employ other mobile access mechanisms such as a Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (UTRAN), Long Term Evolution (LTE), LTE-Advanced (LTE-A), wideband code division multiple access (W-CDMA), CDMA2000, and/or the like. The embodiments of the present invention may also be implemented in future LTE based technologies, such as LTE-A and subsequently developed mobile networks.

The network 6 may include a collection of various different nodes, devices or functions that may be in communication with each other via corresponding wired and/or wireless interfaces. For example, the network may include one or more base stations, such as one or more Base Transceiver Stations (BTSs) and Base Station Controllers (BSCs), node Bs, evolved node Bs (eNBs), access points (AP), relay nodes or the like (all of which being hereinafter generically referenced as an access point (AP)), each of which may serve a coverage area divided into one or more cells. For example, the network may include one or more cells, including, for example, the AP 2, each of which may serve a respective coverage area. The serving cell could be, for example, part of one or more cellular or mobile networks or public land mobile networks (PLMNs). In turn, other devices such as processing devices (e.g., personal computers, server computers or the like) may be coupled to the mobile terminal and/or the second communication device via the network.

The mobile terminals 8 may be in communication with each other or other devices via the network 6. In some cases, each of the mobile terminals may include an antenna or antennas for transmitting signals to and for receiving signals from a base station. In some example embodiments, the mobile terminal 8, also known as a client device, may be a mobile communication device such as, for example, a mobile telephone, portable digital assistant (PDA), pager, laptop computer, tablet computer, or any of numerous other hand held or portable communication devices, computation devices, content generation devices, content consumption devices, universal serial bus (USB) dongles, data cards or combinations thereof. As such, the mobile terminal 8 may include one or more processors that may define processing circuitry either alone or in combination with one or more memories. The processing circuitry may utilize instructions stored in the memory to cause the mobile terminal to operate in a particular way or execute specific functionality when the instructions are executed by the one or more processors. The mobile terminal 8 may also include communication circuitry and corresponding hardware/software to enable communication with other devices and/or the network 6.

Referring now to Fig. 2, an apparatus 20 that may be embodied by or otherwise associated with a mobile terminal 8 (user equipment (UE), such as a cellular phone, a personal digital assistant (PDA), smartphone, tablet computer or the like) or an AP 2 may include or otherwise be in communication with a processor 22, a memory device 24, a communication interface 28, and a user interface 30.

In some example embodiments, the processor 22 (and/or co-processors or any other processing circuitry assisting or otherwise associated with the processor) may be in communication with the memory device 24 via a bus for passing information among components of the apparatus 20. The memory device 24 may include, for example, one or more non-transitory volatile and/or non- volatile memories. In other words, for example, the memory device 24 may be an electronic storage device (e.g., a computer readable storage medium) comprising gates configured to store data (e.g., bits) that may be retrievable by a machine (e.g., a computing device like the processor). The memory device 24 may be configured to store information, data, content, applications, instructions, or the like for enabling the apparatus to carry out various functions in accordance with an example embodiment of the present invention. For example, the memory device could be configured to buffer input data for processing by the processor. Additionally or alternatively, the memory device 24 could be configured to store instructions for execution by the processor 22.

As noted above, the apparatus 20 may, in some embodiments, be embodied by a mobile terminal 8 or an AP 2. However, in some embodiments, the apparatus may be embodied as a chip or chip set. In other words, the apparatus may comprise one or more physical packages (e.g., chips) including materials, components and/or wires on a structural assembly (e.g., a baseboard). The structural assembly may provide physical strength, conservation of size, and/or limitation of electrical interaction for component circuitry included thereon. The apparatus may therefore, in some cases, be configured to implement an embodiment of the present invention on a single chip or as a single "system on a chip." As such, in some cases, a chip or chipset may constitute means for performing one or more operations for providing the functionalities described herein.

The processor 22 may be embodied in a number of different ways. For example, the processor may be embodied as one or more of various hardware processing means such as a coprocessor, a microprocessor, a controller, a digital signal processor (DSP), a processing element with or without an accompanying DSP, or various other processing circuitry including integrated circuits such as, for example, an ASIC (application specific integrated circuit), an FPGA (field programmable gate array), a microcontroller unit (MCU), a hardware accelerator, a special-purpose computer chip, or the like. As such, in some embodiments, the processor may include one or more processing cores configured to perform independently. A multi-core processor may enable multiprocessing within a single physical package. Additionally or alternatively, the processor may include one or more processors configured in tandem via the bus to enable independent execution of instructions, pipelining and/or multithreading. In the embodiment in which the apparatus 20 is embodied as a mobile terminal 8, the processor may be embodied by the processor of the mobile terminal.

In an example embodiment, the processor 22 may be configured to execute instructions stored in the memory device 24 or otherwise accessible to the processor. Alternatively or additionally, the processor may be configured to execute hard coded functionality. As such, whether configured by hardware or software methods, or by a combination thereof, the processor may represent an entity (e.g., physically embodied in circuitry) capable of performing operations according to an embodiment of the present invention while configured accordingly. Thus, for example, when the processor is embodied as an ASIC, FPGA or the like, the processor may be specifically configured hardware for conducting the operations described herein. Alternatively, as another example, when the processor is embodied as an executor of software instructions, the instructions may specifically configure the processor to perform the algorithms and/or operations described herein when the instructions are executed. However, in some cases, the processor may be a processor of a specific device (e.g., a mobile terminal 8) configured to employ an embodiment of the present invention by further configuration of the processor by instructions for performing the algorithms and/or operations described herein. The processor may include, among other things, a clock, an arithmetic logic unit (ALU) and logic gates configured to support operation of the processor.

Meanwhile, the communication interface 28 may be any means such as a device or circuitry embodied in either hardware or a combination of hardware and software that is configured to receive and/or transmit data from/to a network and/or any other device or module in communication with the apparatus 20. In this regard, the communication interface may include, for example, an antenna (or multiple antennas) and supporting hardware and/or software for enabling communications with a wireless communication network. Additionally or alternatively, the communication interface may include the circuitry for interacting with the antenna(s) to cause transmission of signals via the antenna(s) or to handle receipt of signals received via the antenna(s). In order to support multiple active connections simultaneously, such as in conjunction with a digital super directional array (DSD A) device, the communications interface of one embodiment may include a plurality of cellular radios, such as a plurality of radio front ends and a plurality of base band chains. In some environments, the communication interface may alternatively or also support wired communication. As such, for example, the communication interface may include a communication modem and/or other hardware/software for supporting communication via cable, digital subscriber line (DSL), universal serial bus (USB) or other mechanisms.

In some example embodiments, such as instances in which the apparatus 20 is embodied by a mobile terminal 8, the apparatus may include a user interface 30 that may, in turn, be in communication with the processor 22 to receive an indication of a user input and/or to cause provision of an audible, visual, mechanical or other output to the user. As such, the user interface may include, for example, a keyboard, a mouse, a joystick, a display, a touch screen(s), touch areas, soft keys, a microphone, a speaker, or other input/output mechanisms. Alternatively or additionally, the processor may comprise user interface circuitry configured to control at least some functions of one or more user interface elements such as, for example, a speaker, ringer, microphone, display, and/or the like. The processor and/or user interface circuitry comprising the processor may be configured to control one or more functions of one or more user interface elements through computer program instructions (e.g., software and/or firmware) stored on a memory accessible to the processor (e.g., memory device and/or the like).

A new design of system information acquisition procedure for MTC users, such as low cost MTC users with coverage enhancement, is presented. In this procedure, two enhanced master information block (eMIB) patterns are defined and switching between the two patterns is supported.

The Basic Procedure

1) Two eMIB formats are predefined and the eNB chooses between format 1 and format 2 based on the existence of MTC users, such as low cost MTC users with coverage enhancement requirement.

o eMIB format 1 contains all the critical system information;

o eMIB format 2 contains all the critical system information, plus the system information specific for MTC users, such as low cost MTC users. After receiving the eMIB format 2, MTC UEs, such as low cost MTC UEs with coverage enhancement, have enough system information needed to initialize a random access channel (RACH) procedure.

2) UE determines the eMIB format based on the detected primary synchronization signal/secondary synchronization signal (PSS/SSS) transmission scheme, and decodes eMIB accordingly.

3) Necessary system information that is not signaled via eMIB format 1 shall be scheduled via common search space of the physical control channel (PDCCH) with the system information-radio network temporary identifier (SI-RNTI). eMIB format 1 and its transmission scheme

Signaling content

eMIB format 1 contains all the critical system information for all the UEs which do not need coverage enhancement (that is, normal UEs).

There are two possible designs for eMIB format 1 [see Table 1 ] : Table 1

1) The signaling content in eMIB format 1 is the current MIB information plus information about common search space for E-PDCCH;

2) The signaling content in eMIB format 1 is the eMIB format 2 information except that the information specific to MTC users, such as low cost MTC users with coverage enhancement, is dropped.

Transmission scheme eMIB format 1 targets normal UEs, and the transmission scheme is similar to the current PBCH, but increases the resources accordingly if more signaling content is introduced, as in 2) in Table 1. There is no attempt to address the extra coverage enhancement requirement.

About eMIB format 2 and its transmission scheme

Signaling content

eMIB format 2 contains all the critical system information plus the system information specific for MTC users, such as low cost MTC users. After receiving the eMIB format 2, MTC users, such as low cost MTC UEs with coverage enhancement, have enough system information needed to initialize a RACH procedure. One example is given in Table 2. Table 2 Example of eMIB format 2 content

In Table 2, the field [lmtc-radioResourceConfigCommon] is to capture the system information specifically for MTC users, such as low cost MTC users. One example is given in Table 3, where necessary configuration information regarding some downlink (DL) and uplink (UL) physical channels are provided. In practice these parameters may be different from the configurations for normal UEs, most often due to different supported bandwidth or other UE capabilities.

Table 3 Example of configuration specifically for low cost MTC users

— ASNlSTART

c-radioResourceConfigCommon : : = SEQUENCE {

rach-ConfigCommon RACH-ConfigCommon,

pdsch-ConfigCommon PDSCH-ConfigCommon,

pusch-ConfigCommon PUSCH-ConfigCommon,

pucch-ConfigCommon PUCCH-ConfigCommon,

uplinkPowerControlCommon UplinkPowerControlCommon,

ul-CyclicPrefixLength UL-CyclicPrefixLength,

— ASNlSTOP Transmission scheme eMIB format 2 targets itself to MTC users, such as low cost MTC users with coverage enhancement, and to achieve such enhancement, certain repetition or power boosting can be used on the eMIB format 2 transmission. When eMIB format 2 is in use, PSS/SSS signals on the physical channel may also be sent with repetition or power boosting to signal that eMIB format 2 is being sent. The eMIB format 2 signal and the PSS/SSS signal do not necessarily employ the same enhancement method; that is, the eMIB format 2 signals may be sent with power boosting while PSS/SSS may be sent with repetition for enhanced coverage. eNB's choice between eMIB formats

eNB chooses between format 1 and format 2 based on the existence of MTC users, such as low cost MTC users with coverage enhancement requirement. Or eNB chooses between format 1 and format 2 based on a predefined time period; for example, format 2 is used when the eNB enters certain quiet time period, but otherwise utilizes format 1. If eMIB format 2 is used, eNB applies the corresponding transmission scheme to it to ensure coverage.

Different UE types' SI acquisition procedure, and UE's determination of eMIB format and SI procedure

UE determines eMIB format from eNB based on the control signal transmission scheme, and decodes eMIB accordingly. Normal UEs

For example, if normal UE detects that PSS/SSS channels use extra repetitions for coverage enhancement, it shall assume eMIB format 2 is in use. The eMIB format 2 transmission scheme can be defined so that it has a number of repetitions, each of which may be self-decodable. In this case, even if eMIB format 2 is used, normal UEs may not have to receive entire transmissions to decode the system information. This saves the system information overhead compared with transmitting separately to different types of UEs.

If normal UE detects that PSS/SSS is sent without extra repetitions, the exact system information (SI) procedure depends on which eMIB format 1 design is used (see (1) and (2) in Table 1). If it is design 1), the SI procedure is basically according to the existing specification.

It is noted that such optimization requires that normal UE knows the PSS/SSS transmission schemes with and without extra repetition, because otherwise it is not possible for normal UEs to detect and make use of them. MTC users with coverage enhancement

A MTC UE may not be able to decode eMIB format 1 because its transmission scheme is not optimized for the coverage enhancement scenario. In this case, if such UE detects PSS/SSS with coverage enhancement, it shall assume eMIB format 2 is used and the SI acquisition procedure is according to the signaled MIB content while any other necessary SI is scheduled via the common search space of the physical control channel with SI-RNTI.

The above descriptions assume new PSS/SSS channels will be used when coverage enhancement is required. If such new PSS/SSS channels are not used, it is not possible to use step 2 of the proposed procedure. As another possible alternative, a certain small modification can be introduced to the control signal channels, such as the PSS/SSS channels, to indicate eMIB format 2 is in use, for example, by switching the positions of PSS/SSS signals as compared to existing pattern, or by changing the relative positions of PSS/SSS signals. In this alternative, UE may still be able to determine the eMIB format based on PSS/SSS channels detected. If any changes are made to PSS/SSS signals compared with the existing specification, the procedure should be modified so that both types of UEs will be able to blindly detect the exact format of eMIB, for example, based on different payload size of the signaling content. Signaling of other SI not contained in eMIB

Necessary system information that is not signaled via Step 1 shall be scheduled via common search space of the physical control channel with SI-RNTI. This means the system information is conveyed by PDSCH according to the DL grant received. One possibility is that normal UEs need only Basic Procedure 3), but MTC users with coverage enhancement acquire SI based on Basic Procedure 1) and 2) only.

Referring to Fig. 3, a method embodiment is illustrated and may be implemented by an apparatus 20 of Fig. 2 that is embodied by an access point or other network element and that is specifically configured in accordance with Fig. 3. Initially, the apparatus may include means, such as the processor 22, the communications interface 28 or the like, for causing one of at least two eMIB formats to be sent 301. The apparatus may include means, such as the processor or the like, for making a determination of which format to send 303 based on whether the format is intended for normal UE or MTC, e.g., low cost MTC. If the target is normal UE, the apparatus may include means, such as the processor or the like, for selecting the first format 304 containing all critical system information for normal UE networking. Conversely, if the target is an MTC, such as a low cost MTC, the apparatus may include means, such as the processor or the like, for selecting the second eMIB format 305 that targets MTCs, e.g., low cost MTCs, and contains all critical SI for normal UE plus SI for a MTC UE. With the proper eMIB format chosen, the apparatus may include means, such as the processor or the like, for selecting a transmission scheme suited to the chosen eMIB format 307. That selection is made based 309 on which eMIB format was chosen. If the first eMIB format is to be sent, the apparatus may include means, such as the processor or the like, for selecting a first transmission scheme 311 which is a standard master information block in the physical broadcast channel scheme. Alternatively, if the second eMIB format was chosen, the apparatus may include means, such as the processor or the like, for selecting a second transmission scheme 313 to reach MTCs, e.g., low cost MTCs, using at least one of repetition/power boosting for the second eMIB format signals and PSS/SSS repetition and/or power boosting to ensure that such MTCs have the opportunity to receive and decode eMIB. The apparatus may also include means, such as the processor or the like, for switching between eMIB formats based upon criteria including 315 the enhanced coverage requirements of MTCs versus normal coverage for normal UE. The apparatus may include means, such as the processor or the like, for switching between eMIB formats based on criteria that is based 317 on predefined time periods, such a entering quiet time, when MTCs may be reached effectively. The apparatus may include means, such as the processor, the communications interface or the like, for causing any necessary system information that is not signaled in eMIB formats to be sent 319 in the common search space of PDCCH with SI-RNTI.

Another embodiment of the method is illustrated in Fig. 4 that may be implemented by an apparatus 20 of Fig. 2 that is embodied by a mobile terminal, e.g., UE, and specifically configured in accordance with Fig. 4. The apparatus of this embodiment may include means, such as the processor 22 or the like, for causing the PSS/SSS transmission scheme to be detected 401. Once PSS/SSS is detected, the apparatus of this embodiment may include means, such as the processor or the like, for decoding the received eMIB format 403. The apparatus of this embodiment may also include means, such as the processor or the like, for determining 405 whether PSS/SSS was sent with extra repetitions. If not, the apparatus may include means, such as the processor or the like, for determining that the first eMIB format is received 407. If a repetitive PSS/SSS scheme was used, then the apparatus may include means, such as the processor or the like, for determining that the second eMIB format is received 409. The first eMIB format contains and provides all critical system information necessary for normal UE 411. The second format targets MTCs, such as low cost MTCs, and contains not only all critical SI for normal UE but also the necessary SI for MTC UEs to network properly 413.

As described above, Figures 3-4 are flowcharts of a method, apparatus and program product according to example embodiments of the invention. It will be understood that each block of the flowcharts, and combinations of blocks in the flowcharts, may be implemented by various means, such as hardware, firmware, processor, circuitry and/or other device associated with execution of software including one or more computer program instructions. For example, one or more of the procedures described above may be embodied by computer program instructions. In this regard, the computer program instructions which embody the procedures described above may be stored by a memory device 24 of an apparatus 20 employing an embodiment of the present invention and executed by a processor 22 in the apparatus. As will be appreciated, any such computer program instructions may be loaded onto a computer or other programmable apparatus (e.g., hardware) to produce a machine, such that the resulting computer or other programmable apparatus embody a mechanism for implementing the functions specified in the flowchart blocks. These computer program instructions may also be stored in a non-transitory computer-readable storage memory (as opposed to a transmission medium such as a carrier wave or electromagnetic signal) that may direct a computer or other programmable apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture the execution of which implements the function specified in the flowchart blocks. The computer program instructions may also be loaded onto a computer or other programmable apparatus to cause a series of operations to be performed on the computer or other programmable apparatus to produce a computer- implemented process such that the instructions which execute on the computer or other programmable apparatus provide operations for implementing the functions specified in the flowchart block(s). As such, the operations of Figures 3-4, when executed, convert a computer or processing circuitry into a particular machine configured to perform an example embodiment of the present invention. Accordingly, the operations of Figures 3-4 define an algorithm for configuring a computer or processing circuitry (e.g., processor) to perform an example embodiment. In some cases, a general purpose computer may be configured to perform the functions shown in Figures 3-4 (e.g., via configuration of the processor), thereby transforming the general purpose computer into a particular machine configured to perform an example embodiment.

Accordingly, blocks of the flowcharts support combinations of means for performing the specified functions, combinations of operations for performing the specified functions and program instructions for performing the specified functions. It will also be understood that one or more blocks of the flowcharts, and combinations of blocks in the flowcharts, can be implemented by special purpose hardware-based computer systems which perform the specified functions or operations, or combinations of special purpose hardware and computer instructions.

The following list of abbreviations and acronyms is provided as a reference for terms appearing in this description that may also appear in the claims to follow.

3GPP 3rd Generation Partnership Project

BCH Broadcast Channel

CCE Control Channel Element

DCI Downlink Control Information

DL Downlink

eMIB Enhanced Master Information Block

eNB Enhanced Node B. Name for Node B in LTE

E-PDCCH Enhanced Physical Downlink Control Channel

GRPS General Packet Radio Service

GSM Global System for Mobile Communications

LTE Long Term Evolution

LTE-A Long Term Evolution Advanced

MIB Master Information Block

MTC Machine Type Communication

PBCH Physical Broadcast Channel

PCFICH Physical Control Format Indicator Channel

PDCCH Physical Downlink Control Channel

PDSCH Physical Downlink Shared Channel

PHICH Physical Hybrid- ARQ Indicator Channel

PSS Primary Synchronization Signal

RAT Radio Access Technology

RRC Radio Resource Control

SCH Shared Channel

sss Secondary Synchronization Signal

SI System Information

SIB System Information Block

SI-RNTI System Information - Radio Network Temporary Identifier

UE User Equipment

Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

WHAT IS CLAIMED IS:

1. A method comprising:

causing one of at least first and second predefined enhanced master information block (eMIB) formats to be sent; and

selecting a transmission scheme suited to the one of the eMIB formats being sent.

2. The method of claim 1 further comprising:

switching between the at least first and second eMIB formats according to whether receiving devices require coverage enhancement.

3. The method of either of claims 1 and 2 further comprising:

causing system information not signaled in the at least first and second eMIB formats to be sent via common search space of the physical control channel (PDCCH) with the system information-radio network temporary identifier (SI-RNTI).

4. The method of any of claims 1 to 3, wherein the first eMIB format contains critical system information for normal user equipment (UEs).

5. The method of any of claims 1 to 4, wherein the second eMIB format contains critical system information for normal UEs plus system information specific to machine type communication (MTC) UEs.

6. The method of any of claims 1 to 5, wherein the selected transmission scheme for the first eMIB format is the standard MIB information sent according to the physical broadcast channel (PBCH) scheme.

7. The method of any of claims 1 to 6, wherein the selected transmission scheme for the second eMIB format is associated with MTC UEs and employs at least one of repetition or power boosting on eMIB second format signals for enhanced coverage while primary synchronization signal/secondary synchronization signal (PSS/SSS) employs at least one of repetition and power boosting when the second eMIB format is signaled.

8. The method of any of claims 1 to 7, wherein the selection between said first and second eMIB formats is determined by the existence of MTC users with a coverage enhancement requirement.

9. The method of any of claims 1 to 7, wherein the selection between said first and second eMIB formats is based on a predefined time period.

10. A method comprising:

causing a primary synchronization signal/secondary synchronization signal (PSS/SSS) transmission scheme to be received and detected; and

causing an enhanced master information block (eMIB) format to be decoded.

11. The method of claim 10, further comprising:

determining if the PSS/SSS transmission scheme uses extra repetitions, and in the instance that PSS/SSS is received without extra repetitions, determining that a first eMIB format is received, or

in the instance that PSS/SSS is received with extra repetitions, determining that a second eMIB format is received.

12. The method of claim 11 wherein,

the first eMIB format contains critical system information for normal user equipment (UEs).

13. The method of claim 11 wherein,

the second eMIB format is associated with and contains critical system information for machine type communication (MTC) UEs.

14. An apparatus comprising at least a processor, a memory in communicating relation with the processor and having stored computer coded instructions within it, said instructions when executed by the processor causing the apparatus to perform: causing one of at least first and second predefined enhanced master information block (eMIB) formats to be sent; and

15. The apparatus of claim 14, said instructions further causing the apparatus to perform:

16. The apparatus of either of claims 14 and 15, said instructions further causing the apparatus to perform:

17. The apparatus of any of claims 14 to 16, wherein the first eMIB format contains critical system information for normal user equipment (UEs).

18. The apparatus of any of claims 14 to 17, wherein the second eMIB format contains critical system information for normal UEs plus system information specific to machine type communication (MTC) UEs.

19. The apparatus of any of claims 14 to 18, wherein the selected transmission scheme for the first eMIB format is the standard MIB information sent according to the physical broadcast channel (PBCH) scheme.

20. The apparatus of any of claims 14 to 19, wherein the selected transmission scheme for the second eMIB format is associated with MTC UEs and employs at least one of repetition or power boosting on eMIB second format signals for enhanced coverage while primary synchronization signal/secondary synchronization signal (PSS/SSS) employs at least one of repetition and power boosting when the second eMIB format is signaled.

21. The apparatus of any of claims 14 to 20, wherein the selection between said first and second eMIB formats is determined by the existence of MTC users with a coverage enhancement requirement.

22. The apparatus of any of claims 14 to 20, wherein the selection between said first and second eMIB formats is based on a predefined time period.

23. An apparatus comprising at least a processor, a memory in communicating relation with the processor and having stored computer coded instructions within it, said instructions when executed by the processor causing the apparatus to perform:

causing an enhanced master information block (eMIB) format to be decoded.

24. The apparatus of claim 23, said instructions further causing the apparatus to perform:

25. The apparatus of claim 24, wherein the first eMIB format contains critical system information for normal user equipment (UEs).

26. The apparatus of claim 24, wherein the second eMIB format is associated with and contains critical system information for machine type communication (MTC) UEs.

27. The apparatus of any of claims 23 to 26 wherein the apparatus is a mobile phone.

28. The apparatus of any of claims 23 to 26 wherein the apparatus is a machine type communications device.

29. The apparatus of any of claims 14 to 22 wherein the apparatus is one of a wireless network access point, enhanced node B, or base station.

30. A computer program product comprising a non-transitory computer readable medium having stored computer coded instructions, said instructions when executed by a processor causing an apparatus to perform:

31. The computer program product of claim 30 further comprising instructions that cause an apparatus to perform:

32. The computer program product of either of claims 30 and 31 further comprising instructions that cause an apparatus to perform:

33. The computer program product of any of claims 30 to 32 wherein the first eMIB format contains critical system information for normal user equipment (UEs).

34. The computer program product of any of claims 30 to 33 wherein the second eMIB format contains critical system information for normal UEs plus system

information specific to machine type communication (MTC) UEs.

35. The computer program product of any of claims 30 to 34 wherein the selected transmission scheme for the first eMIB format is the standard MIB information sent according to the physical broadcast channel (PBCH) scheme.

36. The computer program product of any of claims 30 to 35 wherein the selected transmission scheme for the second eMIB format is associated with MTC UEs and employs at least one of repetition or power boosting on eMIB second format signals for enhanced coverage while primary synchronization signal/secondary synchronization signal (PSS/SSS) employs at least one of repetition and power boosting when the second eMIB format is signaled.

37. The computer program product of any of claims 30 to 36 wherein the selection between said first and second eMIB formats is determined by the existence of MTC users with a coverage enhancement requirement.

38. The computer program product of any of claims 30 to 36 wherein the selection between said first and second eMIB formats is based on a predefined time period.

39. A computer program product comprising a non-transitory computer readable medium having stored computer coded instructions, said instructions when executed by a processor causing an apparatus to perform:

causing an enhanced master information block (eMIB) format to be decoded.

40. The computer program product of claim 31 further comprising instructions that cause an apparatus to perform: determining if the PSS/SSS transmission scheme uses extra repetitions, and in the instance that PSS/SSS is received without extra repetitions, determining that a first eMIB format is received, or

41. The computer program product of claim 40 wherein the first eMIB format contains critical system information for normal user equipment (UEs).

42. The computer program product of claim 40 wherein the second eMIB format is associated with and contains critical system information for machine type communication (MTC) UEs.

43. An apparatus comprising:

means for causing one of at least first and second predefined enhanced master information block (eMIB) formats to be sent; and

means for selecting a transmission scheme suited to the one of the eMIB formats being sent.

44. The apparatus of claim 43 further comprising:

means for switching between the at least first and second eMIB formats according to whether receiving devices require coverage enhancement.

45. The apparatus of either of claims 43 and 44 further comprising:

means for causing system information not signaled in the at least first and second eMIB formats to be sent via common search space of the physical control channel (PDCCH) with the system information-radio network temporary identifier (SI-RNTI).

46. The apparatus of any of claims 43 to 45 wherein the first eMIB format contains critical system information all normal user equipment (UEs).

47. The apparatus of any of claims 43 to 46 wherein the second eMIB format contains critical system information for normal UEs plus system information specific machine type communication (MTC) UEs.

48. The apparatus of any of claims 43 to 47 wherein the selected transmission scheme for the first eMIB format is the standard MIB information sent according to the physical broadcast channel (PBCH) scheme.

49. The apparatus of any of claims 43 to 48 wherein the selected transmission scheme for the second eMIB format is associated with MTC UEs and employs at least one of repetition or power boosting on eMIB second format signals for enhanced coverage while primary synchronization signal/secondary synchronization signal (PSS/SSS) employs at least one of repetition and power boosting when the second eMIB format is signaled.

50. The apparatus of any of claims 43 to 49 wherein the selection between said first and second eMIB formats is determined by the existence of MTC users with a coverage enhancement requirement.

51. The apparatus of any of claims 43 to 49 wherein the selection between said first and second eMIB formats is based on a predefined time period.

52. An apparatus comprising:

means for causing a primary synchronization signal/secondary synchronization signal (PSS/SSS) transmission scheme to be received and detected; and

means for causing an enhanced master information block (eMIB) format to be decoded.

53. The apparatus of claim 43 further comprising:

means for determining if the PSS/SSS transmission scheme uses extra repetitions, and in the instance that PSS/SSS is received without extra repetitions, means for determining that a first eMIB format is received, or

in the instance that PSS/SSS is received with extra repetitions, means for determining that a second eMIB format is received.

54. The apparatus of claim 53 wherein the first eMIB format contains critical system information for normal user equipment (UEs).

55. The apparatus of claim 53 wherein the second eMIB format is associated with and contains critical system information for machine type communication (MTC) UEs.