CN111373815B

CN111373815B - Method and device for providing access control

Info

Publication number: CN111373815B
Application number: CN201780097020.7A
Authority: CN
Inventors: 李海涛; 张延冀; J-P·科斯基南
Original assignee: Nokia Shanghai Bell Co Ltd; Nokia Solutions and Networks Oy
Current assignee: Nokia Communications (Shanghai) Co., Ltd.; Nokia Solutions and Networks Oy
Priority date: 2017-11-16
Filing date: 2017-11-16
Publication date: 2024-10-29
Anticipated expiration: 2037-11-16
Also published as: WO2019095191A1; CN111373815A

Abstract

A method includes applying, at a user device, an access policy for coverage enhancement level access barring. The access policy depends on a state associated with the user equipment. Different policies may be applied depending on whether the device is mobile or stationary.

Description

Method and apparatus for providing access control

Technical Field

Some embodiments relate to a method and apparatus for providing an access control mechanism.

Background

A communication system may be considered a facility that enables communication sessions between two or more entities, such as user terminals, base stations, and/or other nodes, by providing carriers between the various entities involved in the communication path. The communication system may be provided, for example, by means of a communication network and one or more compatible communication devices. The communication session may include, for example, data communications for carrying communications such as voice, video, electronic mail (email), text messages, multimedia and/or content data, and the like. Non-limiting examples of services provided include two-way or multi-way calls, data communication or multimedia services, and access to data network systems such as the internet.

In a wireless communication system, at least a portion of a communication session between at least two stations occurs over a wireless link. Examples of wireless systems include Public Land Mobile Networks (PLMNs), satellite-based communication systems, and different wireless local area networks, such as Wireless Local Area Networks (WLANs). A wireless system may be generally divided into cells and is therefore generally referred to as a cellular system.

The user may access the communication system by means of a suitable communication device or terminal. The user's communication equipment may be referred to as User Equipment (UE) or user equipment. The communication device is provided with suitable signal receiving and transmitting means to enable communication, for example to enable access to a communication network or communication directly with other users. A communication device may access a carrier provided by a station (e.g., a base station of a cell) and transmit and/or receive communications on the carrier.

Communication systems and associated devices typically operate in accordance with a given standard or specification which sets out what the various entities associated with the system are permitted to do and how that should be achieved. Communication protocols and/or parameters which shall be used for the connection are also typically defined. One example of a communication system is UTRAN (3G radio). Other examples of communication systems are the Long Term Evolution (LTE) of the Universal Mobile Telecommunications System (UMTS) radio access technology and so-called 5G or new radio networks. Standardization of 5G or new radio networks is currently under discussion. LTE is being standardized by the third generation partnership project (3 GPP).

Disclosure of Invention

According to an aspect, there is provided a method comprising: an access policy for coverage enhancement level access barring is applied at a user equipment, the access policy being dependent on a state associated with the user equipment.

The state may be a mobility state of the user equipment.

The status may include the user equipment being one of: stationary user equipment and mobile user equipment.

The method may include: a first access policy for use when the user equipment is mobile and a second access policy for use when the user equipment is stationary are received, and either the first access policy or the second access policy is applied depending on whether the user equipment is stationary or mobile.

The method may include: determining whether the user equipment is a stationary or mobile device and applying a respective one of a first access policy and a second access policy in response to the determination.

The state may be a radio resource management monitoring state.

The state may be a radio resource management neighbor cell monitoring state.

The neighbor cell monitoring status may include one of the following: a neighbor cell monitoring state in which no monitoring is performed, a neighbor cell monitoring state in which neighbor cell measurements are performed on a first time scale, and a neighbor cell monitoring state in which neighbor cell measurements are performed on a second time scale, the second time scale being faster than the first time scale.

The neighbor cell monitoring status may include one of the following: a neighbor cell monitoring state in which no monitoring is performed, loose monitoring, and normal monitoring.

The method may include: the access policy is received at the user equipment.

The method may include: a state is determined at the user equipment and an access policy is selected from a plurality of access policies depending on the determined state.

The applied policies may be associated with a given one or more coverage enhancement levels.

The method may include: a determination is made at a user device that a current coverage enhancement level for the user device is disabled, and responsive to the determination, an attempt is made by the user device to access using a different coverage enhancement level.

This may be performed, for example, by a stationary UE to avoid it being trapped/barred in an overloaded CE level.

This may be associated with no monitoring and/or relaxed monitoring and/or normal monitoring.

The method may include: information is received at the user equipment indicating whether the user equipment is allowed to use a different coverage enhancement level when a current coverage enhancement level for the user equipment is disabled.

The access policy may include information about which of the plurality of control procedures is to be performed.

This information may be provided for a number of different coverage enhancement levels.

Different information may be provided for a plurality of different coverage enhancement levels.

The information may include information indicating that coverage enhancement level prohibition is not performed for one or more coverage enhancement levels.

The information may include information indicating that the coverage enhancement level is prohibited from being performed for one or more coverage enhancement levels when the user equipment is stationary.

The information may include information indicating whether the first inhibit process is to be skipped, and the second inhibit process is performed in response to the information indicating that the first inhibit process is to be skipped.

Depending on, for example, network policy, this may be associated with a stationary user equipment and/or a mobile device. This may be associated with no monitoring and/or relaxed monitoring and/or normal monitoring.

The information may include information indicating that the second inhibit process is not required and the first inhibit process is performed.

Depending on, for example, network policy, this may be associated with a stationary user equipment and/or a mobile user equipment. This may be associated with no monitoring and/or relaxed monitoring and/or normal monitoring.

The first barring procedure may include a cell level barring mechanism.

In some cases, this may be referred to as a "traditional" process. For example, in the context of 3GPP, this may be a previous version of Rel-15.

The second disabling procedure may include coverage enhancement level disabling.

The information may include at least one flag.

The applied policies may include inhibition threshold information for one or more coverage enhancement levels.

For example, this may be associated with a stationary user equipment to allow the stationary user equipment to retry a different CE level when the current CE level is barred.

According to another aspect, there is provided an apparatus in a user equipment, the apparatus comprising: at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to: an access policy for coverage enhancement level access barring is applied at a user equipment, the access policy being dependent on a state associated with the user equipment.

The state may be a mobility state of the user equipment.

The at least one memory and the computer program code may be configured to, with the at least one processor: a first access policy for use when the user equipment is mobile and a second access policy for use when the user equipment is stationary are received, and either the first access policy or the second access policy is applied depending on whether the user equipment is stationary or mobile.

The at least one memory and the computer program code may be configured to, with the at least one processor: determining whether the user equipment is a stationary or mobile device and applying a respective one of a first access policy and a second access policy in response to the determination.

The state may be a radio resource management monitoring state.

The state may be a radio resource management neighbor cell monitoring state.

The neighbor cell monitoring status may include one of the following: a neighbor cell monitoring state in which no monitoring is performed, a relaxed monitoring state, and a normal monitoring state.

The at least one memory and the computer program code may be configured to, with the at least one processor, receive the access policy at the user equipment.

The at least one memory and the computer program code may be configured to, with the at least one processor: a state is determined and an access policy is selected from a plurality of access policies depending on the determined state.

The at least one memory and the computer program code may be configured to, with the at least one processor: it is determined that the current coverage enhancement level is disabled and, in response to the determination, an attempt is made to access using a different coverage enhancement level.

The at least one memory and the computer program code may be configured to, with the at least one processor: information is received indicating whether the user equipment is allowed to use a different coverage enhancement level when the current coverage enhancement level is disabled.

The first barring procedure may include a cell level barring mechanism.

The information may include at least one flag.

According to another aspect, there is provided an apparatus in an access node, the apparatus comprising: at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to: an access policy is communicated to a user for coverage enhancement level access barring, the access policy being dependent on a state associated with the user equipment.

The state may be a mobility state of the user equipment.

The at least one memory and the computer program code may be configured to, with the at least one processor: causing transmission of a first access policy for use when the user equipment is mobile and a second access policy for use when the user equipment is stationary and applying the first access policy or the second access policy depending on whether the user equipment is stationary or mobile.

The at least one memory and the computer program code may be configured to, with the at least one processor: determining whether the user equipment is a stationary or mobile device and providing a respective one of a first access policy and a second access policy in response to the determination.

The state may be a radio resource management monitoring state.

The state may be a radio resource management neighbor cell monitoring state.

The at least one memory and the computer program code may be configured to, with the at least one processor: information is caused to be transmitted to the user equipment indicating whether the user equipment is permitted to use a different coverage enhancement level when a current coverage enhancement level for the user equipment is disabled.

Depending on, for example, network policy, this may be associated with a stationary user equipment and/or a mobile device.

Depending on, for example, network policy, this may be associated with a stationary user equipment and/or a mobile user equipment.

The first barring procedure may include a cell level barring mechanism.

The information may include at least one flag.

According to another aspect, there is provided a method comprising: an access policy is communicated to a user for coverage enhancement level access barring, the access policy being dependent on a state associated with the user equipment.

The state may be a mobility state of the user equipment.

The method may include: causing transmission of a first access policy for use when the user equipment is mobile and a second access policy for use when the user equipment is stationary and applying the first access policy or the second access policy depending on whether the user equipment is stationary or mobile.

The method may include: determining whether the user equipment is a stationary or mobile device and providing a respective one of a first access policy and a second access policy in response to the determination.

The state may be a radio resource management monitoring state.

The state may be a radio resource management neighbor cell monitoring state.

The method may include: information is caused to be transmitted to the user equipment indicating whether the user equipment is permitted to use a different coverage enhancement level when the current coverage enhancement level of the user equipment is disabled.

The first barring procedure may include a cell level barring mechanism.

The information may include at least one flag.

A computer program may also be provided, comprising program code means adapted to perform the method(s). The computer program may be stored and/or otherwise implemented by means of a carrier medium. The computer program may be provided on a non-transitory computer program carrier medium.

Many different embodiments have been described above. It should be appreciated that additional embodiments may be provided by combinations of any two or more of the above embodiments.

Various other aspects and additional embodiments are also described in the following detailed description and the appended claims.

Drawings

Some embodiments will now be described, by way of example only, with reference to the following drawings, in which:

FIG. 1 shows a schematic diagram of an example communication system including a base station and a plurality of communication devices;

FIG. 2 shows a schematic diagram of an example mobile communication device;

FIG. 3 illustrates a schematic diagram of an example control device; and

Fig. 4 shows a method flow.

Detailed Description

Before explaining examples in detail, certain general principles of wireless communication systems and mobile communication devices are briefly explained with reference to fig. 1 to 3 to help understand the underlying technology of the described examples.

In a wireless communication system 100 such as that shown in fig. 1, wireless communication devices (e.g., user Equipment (UE) 102, 104, 105) are provided wireless access via at least one base station or similar wireless transmission and/or reception wireless infrastructure node or point. Such a node may be, for example, a base station or eNodeB (eNB), or in a 5G system, a next generation NodeB (gNB), or other wireless infrastructure node. These nodes will generally be referred to as base stations. The base station is typically controlled by at least one suitable controller means to effect its operation and management of mobile communication devices in communication with the base station. The controller device may be located in a radio access network (e.g., wireless communication system 100) or in a Core Network (CN) (not shown) and may be implemented as one central device or its functions may be distributed over several devices. The controller means may be part of the base station and/or provided by a separate entity such as a radio network controller. In fig. 1, control means 108 and 109 are shown as controlling the respective macro level base stations 106 and 107. In some systems, the control means may additionally or alternatively be provided in the radio network controller. Other examples of radio access systems include radio access systems provided by base stations of systems based on technologies such as 5G or new radio, wireless Local Area Network (WLAN) and/or WiMax (worldwide interoperability for microwave access). The base station may provide coverage for an entire cell or similar radio service area.

In fig. 1, base stations 106 and 107 are shown connected to a wider communication network 113 via gateway 112. Additional gateway functions may be provided to connect to another network.

The smaller base stations 116, 118 and 120 may also be connected to the network 113, for example by separate gateway functions and/or via controllers of macro-level stations. The base stations 116, 118, and 120 may be pico or femto base stations, or the like. In this example, stations 116 and 118 are connected via gateway 111, while station 120 is connected via controller device 108. In some embodiments, smaller stations may not be provided.

A possible wireless communication device will now be described in more detail with reference to fig. 2, fig. 2 showing a schematic partial cross-sectional view of a communication device 200. Such communication devices are often referred to as User Equipment (UE) or terminals. A suitable mobile communication device may be provided by any device capable of transmitting and receiving radio signals. Non-limiting examples include a Mobile Station (MS) or mobile device (such as a mobile phone or so-called "smart phone"), a computer provided with a wireless interface card or other wireless interface facility (e.g., a USB dongle), a Personal Data Assistant (PDA) or tablet provided with wireless communication capabilities, or any combination of these devices, etc. A mobile communication device may provide, for example, data communication for carrying communications such as voice, electronic mail (email), text messages, multimedia, and the like. Thus, many services can be offered and provided to a user via the user's communication device. Non-limiting examples of such services include two-way or multi-way calls, data communications or multimedia services, or simply include access to a data communications network system, such as the internet. Broadcast or multicast data may also be provided to the user. Non-limiting examples of content include downloads, television and radio programming, video, advertising, various alerts, and other information.

The wireless communication device may be, for example, a mobile device, i.e., a device that is not fixed to a particular location, or it may be a stationary device.

The wireless device may or may not require human-machine interaction to communicate. The latter devices are sometimes referred to as MTC (machine type communication) devices. Such a device may have only a subset of the components shown in fig. 2 and/or a simplified version of the components. In the present teachings, the term "UE" is used to refer to any type of wireless communication device.

A mixture of different types of devices may be configured to operate within a network.

The communication device 200 may receive signals over the air or radio interface 207 via suitable means for receiving and may transmit signals via suitable means for transmitting radio signals. In fig. 2, the transceiver device is schematically represented by block 206. The transceiver means 206 may be provided, for example, by means of a radio part and an associated antenna arrangement. The antenna arrangement may be arranged inside or outside the wireless device.

The wireless device is typically provided with at least one data processing entity 201, at least one memory 202 and possibly other components 203 for performing tasks it is designed to perform with the aid of software and hardware, including control of access to and communication with access systems and other communication devices. The data processing, storage and other associated control means may be provided on a suitable circuit board and/or in a chipset. This feature is indicated by reference numeral 204.

Alternatively, the user may control the operation of the wireless device by means of a suitable user interface, such as a keypad 205, voice commands, touch sensitive screen or pad, combinations thereof, or the like. A display 208, speaker and microphone may optionally be provided.

Further, the wireless communication device may optionally include suitable connectors (wired or wireless) to other devices and/or for connecting external accessories (e.g., hands-free devices) thereto. The communication devices 102, 104, 105 may access the communication system based on various access technologies.

Fig. 3 shows an example of an apparatus that may be provided in a base station. The apparatus 300 comprises at least one memory 301, at least one data processing unit 302, 303 and an input/output interface 304. Via the interface, the control means may be coupled to a receiver and a transmitter of the base station. The receiver and/or transmitter may be implemented as a radio front-end or a remote radio head. For example, the control device 300 or the processor 201 may be configured to execute appropriate software code to provide control functions.

The narrowband LTE system may support Machine Type Communication (MTC) or machine-to-machine communication (M2M). This narrowband LTE system may sometimes be referred to as LTE-M.

The internet of things (IoT) is known. IoT includes interworking of interconnected devices (including but not limited to user equipment, vehicles, home appliances, etc.). Narrowband IoT (NB-IoT) is a radio technology standard for enabling IoT devices to communicate using a cellular network. Improvements to NB-IoT are underway.

The goal of NB-IoT enhancement and LTE-M is to enhance access barring. This may be used to improve access and/or load control in idle mode, e.g. access barring based on CE (coverage enhancement) levels.

Coverage enhancement CEs have been proposed. CE has been proposed to address issues such as the need to extend the range and/or coverage associated with a base station. CE may be implemented by, for example, increasing the number of repetitions of transmission. The CE may have a number of different levels. The number of different levels may be any suitable number. For example, current proposals have up to 4 levels for LTE-M and up to 3 levels for NB-IoT. Different offers may have different levels. Each level may be associated with a different number of transmission repetitions.

In some embodiments, access by a UE to a particular cell may be barred or restricted depending on CE level and/or mode.

A UE with a higher CE level may require more resources than a UE with a lower CE level. In some embodiments, the probability of the UE obtaining resources may be the same regardless of CE level. In other embodiments, the probability of the UE obtaining resources may depend on the CE level.

Currently, with the LTE specifications, NB-IoT access control features are referred to as access barring AB, separately from LTE access control mechanisms. The access barring may be intended for delay tolerant services, such as Machine Type Communication (MTC) services that do not have stringent delay requirements. The prohibition bitmap may be transmitted in a system information block. It has been proposed to transmit this information in a narrowband system information block SIB. This information may be sent separately from other system information. So-called SIB14 or SIB2 has been proposed to transmit the bitmap information. The bitmap information may be transmitted only when access control is enabled.

Currently, neither NB-IoT nor LTE-M support load balancing between different CE levels when accessing cells.

Potentially, the base station may restrict access to certain CE level users to avoid overload. Different CE levels may be associated with different radio resources. For example, PRACH (physical random access channel) resources may be separated for different CE levels. This may be CE level(s) or pattern(s) associated with a relatively high repetition rate. For UEs with always poor coverage, fairness issues may arise, for example, UEs in the form of stationary underground electricity meters. If the UEs are not differentiated when accessing the NW, these stationary UEs may not have a better chance to establish a connection than other UEs that just move to the cell edge. The meter report may then be delayed or lost.

Consider the following: for an always stationary meter, the access probability set for CE level is small. These meters may be barred most of the time when attempting to send data to the network, but the mobile UE may have an opportunity to move to other CE levels with a higher probability of access and thus a higher opportunity to gain access.

In one case, a stationary UE may stay at the most robust repetition level (i.e., the most number of repetitions). The CE level may be level 3. This may be due to congestion at this level at high loads. For example, a part of mobile UEs also depend on the same level. This may result in stationary UEs staying at the CE level because the UEs are in a stationary, unchanged radio environment, while a mobile UE may desire a dynamic radio environment to disengage the UE from the CE level.

In some embodiments, different access probabilities for stationary UEs and mobile UEs may be provided such that a portion of mobile UEs may be moved out of the CE level in question. This may be achieved by disabling a proportion of these mobile UEs from the CE level. This may reduce congestion from stationary UEs in the CE level. These probabilities may be in units of per CE level, or may be specifically applied to CE levels. The base station may provide different access probabilities to the UE. As another alternative, the base station may provide a common probability for each CE level or a particular CE level and an additional scaling factor to the stationary UE from which the access probability for the stationary UE may be derived. The UE itself may determine whether it is stationary or mobile and then apply the appropriate access probability. Alternatively or additionally, this may be determined by the base station and signaled to the UE.

Access barring may address congestion on the PRACH. For eMTC (enhanced MTC) and NB-IoT, different resources are used for PRACH at each CE level. This may provide finer granularity for the network to perform congestion control at each CE level.

For a given access barring, there may be an associated access probability (sometimes referred to as a barring factor) and access class barring time. When the UE requests access, it derives a random number between 0 and 1 and compares the number with the access probability. When the number is less than the access probability, the device proceeds to a random access procedure. Otherwise, the device will be disabled for a period of time before attempting to access the network again.

Some embodiments may relate to an access barring mechanism for one or more of: NB-IoT, LTE-M and NR UE. Of course, other embodiments may involve any other suitable criteria.

Some embodiments may distinguish stationary UEs from mobile UEs and apply different access policies for stationary UEs and mobile UEs. Any suitable parameters may be used to distinguish between UEs. This may be based on, for example, RSRP (reference signal received power) variation of the serving cell or cell reselection count/result. In some embodiments, different access policies for stationary UEs and mobile UEs may be applied.

Some embodiments may provide one or more options to enhance the access barring mechanism for different CE levels.

In some embodiments, different barring factors/probabilities for different CE levels are signaled to the UE. This may allow the network to set different access probabilities according to an estimate of the number/distribution of UEs and/or access activity in each CE level.

In some embodiments, an indication is provided as to whether the UE is allowed to attempt to access the cell at another CE level when the current CE level is barred. This is because the traffic load at different CE levels may be independent and that one CE level is overloaded does not necessarily mean that the other CE level is also overloaded. This may allow the UE to access the network via a less loaded CE level when the cell is barred from being in the current overloaded CE level.

In some embodiments, a skip indication is provided to allow the UE to skip existing barring mechanisms and directly perform CE level based access barring. If for some reason the network has to set the existing barring factor relatively high, it is likely that the UE will not be able to pass access control even if the CE level specific barring factor is not so high for some CE levels. In this case, skipping the existing barring mechanism may help the UE to more efficiently apply radio resources through access control.

The UE may be signaled which access barring mechanism the UE should follow. The base station may define the access barring mechanism according to policies followed by the base station.

The UE may be signaled: for a certain CE level, it is allowed to ignore the prohibition based on CE level. For example, for a stationary UE at an overloaded CE level, if the network wants to have the UE access, ignoring the CE level based barring may avoid the UE being barred in that CE level.

The UE may determine that the UE is allowed to ignore the CE level based prohibition. For example, as described above, stationary UEs may benefit from it, otherwise stationary UEs will always be barred by an overloaded CE level.

The inhibit function may be based on RRM (radio resource management monitoring).

It should be appreciated that some embodiments may use a single one of the options described above or a combination of two or more options.

Signaling from an access point or base station may be via broadcast communications and/or via dedicated signaling.

Referring to fig. 4, fig. 4 illustrates a method of an embodiment.

In step S1, the base station will broadcast or signal the barring factors for different CE levels. This may be for all UEs in a cell, for all LTE-M UEs in a cell, for all NB-IoT UEs in a cell, or for a particular UE. This is in contrast to existing arrangements in which one access control probability is provided for the UE. This barring factor is used for access control and is different from the weighting factor for the PRACH for anchor/non-anchor PRBs (physical resource blocks). These weighting factors may be broadcast to the UE and may be used by the UE to select the PRBs on which it transmits the random access preamble.

In step S2, it is determined whether the UE has passed a given level of access control.

If so, the next step is step S3, in which the UE can select PRBs based on the weighting factors of anchor/non-anchor PRBs to perform RA (random access procedure) on a given CE level only after the UE has passed the access control of that CE level. A given CE level may be selected by the UE depending on one or more factors. For example, the CE level may be selected based on the measured RSRP reference signal received power and/or RSRQ reference signal received quality, etc. In other embodiments, alternatively or additionally, the CE level may be selected depending on the amount of data the UE has to transmit. In other embodiments, the base station may determine the CE level based on one or more factors. If the base station selects the selected CE level, the selected CE level may be signaled to the UE.

In some embodiments, the base station may signal to the UE whether the UE is allowed to attempt to access the cell at another CE level. For example, if the cell is barred from being in the current CE level (e.g., the CE level associated with the measured RSRP result), the base station may indicate that the UE is allowed to attempt a different, deeper (higher repetition rate) CE level. The allow/disallow indication may be signaled per cell or per CE level. This may be beneficial because the traffic load of different CE levels may be independent and that one CE level is overloaded does not necessarily mean that the other CE level is also overloaded. It should be understood that this information may be transmitted together with the information in step S1 or may be transmitted separately. In some embodiments, the information of step S1 may be broadcast and this additional information regarding whether the UE is allowed to access the cell at another CE level may be signaled to the UE.

In an embodiment providing additional information, when it is determined that the UE does not pass a given level of access control, the next step is step S4, in which it is determined whether the UE is allowed to attempt another level.

If so, the next step is S5, in which it is determined whether the UE has passed access control at the new CE level.

If so, the next step is S3, and if not, the next step is step S4.

It should be appreciated that in the case where the UE is allowed to attempt another level, the UE may need to first perform n attempts to access a given level before it is allowed to attempt to access the next CE level. N is an integer greater than or equal to 1.

In some embodiments, alternatively or additionally, the allowed/disallowed attempts to another CE level may be determined based on a barring factor threshold configured by the base station. For example, only those CE levels with a sufficiently low barring factor (e.g., below a barring factor threshold) are allowed to retry to access at another CE level. The threshold may be signaled by the base station. For example, the threshold may be broadcast by the base station along with a factor of inhibition for each CE level. For example, when the barring factor is lower than, for example, 0.3, the CE level may be allowed to retry the access.

In some embodiments, the base station may configure the UE configuration to skip existing legacy barring mechanisms and directly perform CE level based access barring checks such as discussed with respect to fig. 4. The conventional barring mechanism is a cell level barring mechanism. Whenever a UE wants to access the cell, the UE draws a random number and checks if it is less than the cell level barring factor. If so, the UE is allowed to perform the RA procedure; if not, the cell is barred.

In some embodiments, CE level access barring may be disabled according to an indication from the base station for a particular CE level (e.g., when the barring factor is too high and thus blocking access). The indication may be a flag or indication for CE level. The purpose of the indication may be to disable access barring for the CE level. This means that the UE does not need to perform the barring control for the CE level as long as the UE passes the legacy (cell level) barring control.

In some embodiments, the UE may skip the legacy (cell level) barring control and directly perform the CE level barring control. This may be indicated by the base station.

The base station may indicate whether or not to allow ignoring CE-level based access control for a certain CE level. This may be provided in a system information broadcast or the like. When and/or what may occur when CE-level based access control is ignored may be determined by the UE according to one or more criteria defined by the base station.

The UE may determine from an evaluation of its stationary state whether it can ignore CE-level based access control, e.g. by detecting a change in its serving cell RSRP or cell reselection count.

Once the CE-level based access control has been ignored, the UE may perform a normal AC check during the initial access. The goal may be to avoid fairness issues for those stationary UEs that always need deeper CE levels. This means that as long as the UE passes the normal AC check, it is allowed to access the cell using the CE level without further performing CE level-based access control for the CE level.

For a subsequent transition from the idle state to the connected state, the UE may ignore CE-level based AC and perform a normal AC procedure if the UE satisfies one or more of the following conditions:

The UE attempts to establish a connection using the same cell as the last serving cell in a connected state;

The UE operates at a certain CE level indicated by the base station during the connected state

Upon initiating a state transition, the UE remains at the same CE level

In some embodiments, the different barring actions may be based on UE RRM monitoring, i.e. the UE applies barring based on the UE RRM neighbor cell monitoring state, e.g. as follows:

1) Without monitoring

In this case, the UE may select legacy barring. Alternatively or additionally, the inhibit check is performed only for certain CE level(s)

2) Relaxation monitoring

For example, the UE may select CE level barring. Alternatively or additionally, the inhibit check is performed only for certain CE level(s).

3) Normal monitoring

For example, the UE may select two prohibit mechanisms. The UE may sequentially perform AC: first, it is a legacy cell level AC, if passing, a CE level AC, if passing, the UE is allowed to perform RA procedure for the CE level. Alternatively or additionally, the inhibit check is performed only for certain CE level(s).

In some embodiments, only one of the monitoring states is provided. It should be appreciated that in some embodiments, two or more of these monitoring states may be provided.

The UE may dynamically determine whether to apply relaxation monitoring through a change in serving cell RSRP or the like. If there are configuration parameters for dynamically determining whether to apply relaxation monitoring, these configuration parameters may be provided by means of system information. The relaxation monitoring may be applicable when the UE is below a neighbor cell measurement threshold (such as Sintrasearch or Sintersearch threshold, respectively) (if already configured).

A UE applying "relaxation monitoring" may need to perform neighbor cell measurements on a relatively slow time scale, regardless of whether the UE deems itself stationary.

The slow time scale may be the same or different for different UEs.

The UE may apply neighbor cell measurements "normal mobility requirements" or "relaxed monitoring requirements".

Some embodiments may provide one or more of the following advantages.

Some embodiments may implement load balancing between different CE levels.

Some embodiments may allow offloading from a congested CE level to another CE level. This may reduce latency and/or improve resource utilization efficiency.

Some embodiments may address fairness issues for stationary UEs that are always in poor coverage locations.

In LTE, the ACB mechanism includes a set of access categories. For example, categories 0 to 9 are for regular users, category 10 is for emergency calls, and categories 11 to 15 are for high priority or operator services.

It should be appreciated that embodiments may be used with any suitable standard. Some embodiments may be used with narrowband arrangements such as NB-LTE, LTE-M, and NB-IoT. However, these are merely examples, and some embodiments may be used in any other suitable scenario. Some embodiments may be used with non-narrowband scenes.

It should be understood that these means may comprise or be coupled to other units or modules etc., such as radio parts or radio heads for transmission and/or reception. Although the apparatus has been described as one entity, the different modules and memories may be implemented in one or more physical or logical entities.

Although certain embodiments are described above by way of example with reference to certain example architectures for wireless networks, technologies and standards, embodiments may be applied to any other suitable form of communication system than those shown and described herein.

It should also be noted herein that while the above describes exemplifying embodiments, there are several variations and modifications which may be made to the disclosed solution without departing from the scope of the present invention.

In general, the various embodiments may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects of the invention may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device, although the invention is not limited thereto. While various aspects of the invention may be illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

Embodiments of the invention may be implemented by computer software executable by a data processor of a mobile device, such as in a processor entity, or by hardware, or by a combination of software and hardware. Computer software or programs (also referred to as program products) including software routines, applets, and/or macros can be stored in any apparatus-readable data storage medium and they include program instructions for performing particular tasks. The computer program product may include one or more computer-executable components configured to perform embodiments when the program is run. The one or more computer-executable components may be at least one software code or a portion thereof.

In addition, in this regard, it should be noted that any blocks of the logic flows as illustrated may represent program steps, or interconnected logic circuits, blocks and functions, or a combination of program steps and logic circuits, blocks and functions. The software may be stored on a physical medium such as a memory chip or memory block implemented within a processor, a magnetic medium such as a hard or floppy disk, and an optical medium such as, for example, a DVD and its data variants, a CD. The physical medium is a non-transitory medium.

The memory may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. The data processor may be of any type suitable to the local technical environment and may include, as non-limiting examples, one or more of the following: general purpose computers, special purpose computers, microprocessors, digital Signal Processors (DSPs), application Specific Integrated Circuits (ASICs), FPGAs, gate level circuits, and processors based on a multi-core processor architecture.

Embodiments of the invention may be practiced in various components such as integrated circuit modules. The design of integrated circuits is generally a highly automated process. Complex and powerful software tools are available for converting a logic level design into a semiconductor circuit design ready to be etched and formed on a semiconductor substrate.

The above description provides a complete and informative description of exemplary embodiments of the invention by way of non-limiting example. However, various modifications and adaptations may become apparent to those skilled in the relevant arts in view of the foregoing description, when read in conjunction with the accompanying drawings and the appended claims. However, all such and similar modifications of the teachings of this invention will still fall within the scope of this invention as defined in the appended claims. Indeed, there are additional embodiments that include a combination of one or more embodiments with any of the other embodiments previously discussed.

Claims

1. A method for communication, comprising:

An access policy for coverage enhanced level access barring is applied at a user equipment, the access policy depending on a state associated with the user equipment, wherein the state is a radio resource management neighbor cell monitoring state, wherein the neighbor cell monitoring state comprises one of: a neighbor cell monitoring state in which no monitoring is performed, a neighbor cell monitoring state in which neighbor cell measurements are performed on a first time scale, and a neighbor cell measurement state in which neighbor cell measurements are performed on a second time scale, the second time scale being faster than the first time scale.

The method according to claim 1 , wherein the status further comprises a mobility status of the user equipment.

3. The method according to claim 1 or 2, wherein the state comprises a state when the user equipment is one of the following: a stationary user equipment and a mobile user equipment.

4. The method according to claim 2 includes: receiving a first access policy and a second access policy, wherein the first access policy is used when the user equipment is mobile, and the second access policy is used when the user equipment is stationary, and applying the first access policy or the second access policy depends on whether the user equipment is stationary or mobile.

5. The method of claim 4, comprising determining whether the user equipment is a stationary or mobile mobile device, and applying a corresponding one of the first access policy and the second access policy in response to the determination.

6. The method according to claim 1 or 2, comprising determining a state at the user equipment and selecting an access policy from a plurality of access policies depending on the determined state.

The method of claim 6 , wherein the applied policy is associated with a given one or more coverage enhancement levels.

8. The method of claim 1 or 2, comprising: determining at the user equipment that a current coverage enhancement level for the user equipment is prohibited, and in response to the determination, attempting, by the user equipment, to access using a different coverage enhancement level.

9. The method of claim 8, comprising receiving at the user equipment information indicating whether the user equipment is permitted to use a different coverage enhancement level when the current coverage enhancement level for the user equipment is prohibited.

10. The method according to claim 1 or 2, wherein the access policy includes information about which control process among a plurality of control processes is to be executed.

11. The method of claim 10, wherein the information comprises information indicating that coverage enhancement level prohibition is not performed for one or more coverage enhancement levels when the user equipment is stationary.

12 . The method of claim 10 , wherein the information includes information indicating whether a first inhibiting process is to be skipped, and the second inhibiting process is performed in response to the information indicating that the first inhibiting process is to be skipped.

13. The method of claim 1 or 2, wherein the applied policy includes prohibition threshold information for one or more coverage enhancement levels.

14. A method for communication, comprising: causing an access policy to be transmitted to a user equipment for coverage enhancement level access barring, the access policy depending on a state associated with the user equipment, wherein the state is a radio resource management neighbor cell monitoring state, wherein the neighbor cell monitoring state comprises one of: a neighbor cell monitoring state in which no monitoring is performed, a neighbor cell monitoring state in which neighbor cell measurements are performed on a first time scale, and a neighbor cell measurement state in which neighbor cell measurements are performed on a second time scale, the second time scale being faster than the first time scale.

The method of claim 14 , wherein the status further comprises a mobility status of the user equipment.

16. A computer readable storage medium having stored thereon a computer program, the computer program comprising computer executable code which, when executed on at least one processor, causes the method according to any preceding claim to be performed.

17. An apparatus in an access node, comprising: at least one processor and at least one memory, the at least one memory including computer program code, the at least one memory and the computer program code being configured to, together with the at least one processor, cause the apparatus to at least:

An access policy is caused to be transmitted to a user equipment for coverage enhancement level access barring, the access policy depending on a state associated with the user equipment, wherein the state is a radio resource management neighbor cell monitoring state, wherein the neighbor cell monitoring state comprises one of: a neighbor cell monitoring state in which no monitoring is performed, a neighbor cell monitoring state in which neighbor cell measurements are performed on a first time scale, and a neighbor cell measurement state in which neighbor cell measurements are performed on a second time scale, the second time scale being faster than the first time scale.

18. The apparatus of claim 17, wherein the state further comprises a mobility state of the user equipment.