Patent Application
20110228680
Examples of the present invention relate to power control and resource allocation. More specifically, the examples of the present invention relate to methods, apparatuses, a system, a related computer program product and a data structure for power control and resource allocation. Examples of the present invention may be applicable to radio communication networks.
Frequency spectrum for radio communication is a scarce resource. For this reason, existing technologies including third generation partnership project/3GPP2 (3GPP/3GPP2) second generation/third generation (2G/3G) technologies (such as global system for mobile communication/enhanced data rates for global evolution (GSM/EDGE), code division multiple access 2000 (CDMA2000™) or wide-band CDMA (WCDMA)) as well as other 2G narrowband radio technologies are subsequently substituted by more spectrally efficient broadband technologies including but not limited to 3GPP long term evolution (LTE).
While LTE adheres to rather relaxed spectrum emission mask (SEM) and adjacent channel leakage requirements (ACLR), LTE may create challenges in coexistence situations with existing technologies, such as WCDMA or GSM and other 2G narrowband technologies including e.g. public safety in the U.S. or transportation communication in Japan.
E.g. in LTE Release 8 (Rel-8), uplink (UL) power control is supported e.g. for the physical uplink shared channel (PUSCH), the physical uplink control channel (PUCCH), and for the sounding reference symbol (SRS). Consistently, there is also a power ramp-up procedure for the physical random access channel (PRACH).
The same power control principles are used for PUSCH, PUCCH, and SRS, possibly with some specific differences in the power control formulae. Open loop and closed loop power control may be provided in all cases.
The maximum UE transmit power is limited by a general maximum value Pmax which is broadcast and valid per LTE cell. It is to be noted that the term “broadcast” may also comprise e.g. “signaling via RRC” and also “Pmax defined by a UE class, i.e. without signaling from network”. For instance, the open loop and/or closed loop power control formula for PUSCH yields for the UE transmit power P(i) in the i-th transmission time interval (TTI):
P(i)=min{Pmax,P0
Pmax is the maximum UE transmit power broadcast e.g. for the LTE cell. P0
In consideration of the above, according to examples of the present invention, methods, apparatuses, a system, a related computer program product and a data structure for power control and resource allocation are provided.
According to an example of the present invention, in a first aspect, this object is for example achieved by a method comprising:
transmitting, to each selected one of a plurality of terminals, a network control message comprising a plurality of limit values, each of the limit values being related to a first network communication parameter in relation to a second network communication parameter and being individually set for the selected terminal, based on a detected communication condition of each one of the plurality of terminals.
According to further refinements of the example of the present invention as defined under the above first aspect,
the method further comprises selecting one or more out of the plurality of terminals based on the detected communication condition;
the method further comprises setting the plurality of limit values based on the detected communication condition of the plurality of terminals;
the method further comprises detecting the communication condition of each one of the plurality of terminals;
the detecting further comprises receiving one of a power headroom report, a received signal strength indication and a timing advance information;
the method further comprises allocating a communication resource for the plurality of terminals based on the detected communication condition;
the allocating further comprises delaying of allocation;
the method further comprises monitoring the detected communication condition and, if the monitored communication condition has changed, changing the plurality of set limit values according to the changed communication condition.
According to an example of the present invention, in a second aspect, this object is for example achieved by a method comprising:
configuring a terminal according to a first network communication parameter in relation to a second network communication parameter based on a received network control message comprising a plurality of limit values, each of the limit values being related to the first network communication parameter in relation to the second network communication parameter and being individually set for the terminal.
According to further refinements of the example of the present invention as defined under the above second aspect,
the method further comprises receiving the network control message from a base station;
the method further comprises acknowledging successful receipt of the network control message to the base station;
the method further comprises transmitting one of a power headroom report, a received signal strength indication and a timing advance information.
According to further refinements of the example of the present invention as defined under the above first and second aspects,
the network control message is a radio resource control system information message;
the radio resource control system information message is transmitted via a physical downlink shared channel;
the radio resource control system information message refers to configuration parameters for power control and resource allocation for one of a physical uplink shared channel, a physical uplink control channel and a sounding reference symbol channel;
the set limit values are used in an uplink direction from the terminals to a base station;
the first network communication parameter is a transmitting power of each one of the plurality of terminals;
the second network communication parameter is a frequency band to be used by each one of the plurality of terminals;
one of the limit values is broadcast to each one of the plurality of terminals, and the remaining limit values are set and transmitted individually in each network control message;
a terminal entering a cell surrounding a base station is set to the highest available limit value;
the limit value set for a given terminal is set higher as the detected communication condition is determined to be less sufficient;
the limit value set for a given terminal is set lower as the detected communication condition is determined to be more sufficient;
the limit value for a transmitting power set for a given terminal is set higher as a frequency band related to the limit value is determined to be further away from a forbidden frequency band;
the limit value for a transmitting power set for a given terminal is set lower as a frequency band related to the limit value is determined to be closer to a forbidden frequency band.
According to an example of the present invention, in a third aspect, this object is for example achieved by an apparatus comprising:
means for transmitting, to each selected one of a plurality of terminals, a network control message comprising a plurality of limit values, each of the limit values being related to a first network communication parameter in relation to a second network communication parameter and being individually set for the selected terminal, based on a detected communication condition of each one of the plurality of terminals.
According to further refinements of the example of the present invention as defined under the above third aspect,
the apparatus further comprises means for selecting one or more out of the plurality of terminals based on the detected communication condition;
the apparatus further comprises means for setting the plurality of limit values based on the detected communication condition of the plurality of terminals;
the apparatus further comprises means for detecting the communication condition of each one of the plurality of terminals;
the means for detecting further comprises means for receiving configured to receive one of a power headroom report, a received signal strength indication and a timing advance information;
the apparatus further comprises means for allocating a communication resource for the plurality of terminals based on the detected communication condition;
the means for allocating further comprises means for delaying of allocation;
the apparatus further comprises means for monitoring the detected communication condition and, means for changing, if the monitored communication condition has changed, the plurality of set limit values according to the changed communication condition.
According to an example of the present invention, in a fourth aspect, this object is for example achieved by an apparatus comprising:
means for configuring a terminal according to a first network communication parameter in relation to a second network communication parameter based on a received network control message comprising a plurality of limit values, each of the limit values being related to the first network communication parameter in relation to the second network communication parameter and being individually set for the terminal.
According to further refinements of the example of the present invention as defined under the above fourth aspect,
the apparatus further comprises means for receiving the network control message from a base station;
the apparatus further comprises means for acknowledging successful receipt of the network control message to the base station;
the apparatus further comprises means for transmitting one of a power headroom report, a received signal strength indication and a timing advance information.
According to further refinements of the example of the present invention as defined under the above third and fourth aspects,
the network control message is a radio resource control system information message;
the radio resource control system information message is transmitted via a physical downlink shared channel;
the radio resource control system information message refers to configuration parameters for power control and resource allocation for one of a physical uplink shared channel, a physical uplink control channel and a sounding reference symbol channel;
the set limit values are used in an uplink direction from the terminals to a base station;
the first network communication parameter is a transmitting power of each one of the plurality of terminals;
the second network communication parameter is a frequency band to be used by each one of the plurality of terminals;
one of the limit values is broadcast to each one of the plurality of terminals, and the remaining limit values are set and transmitted individually in each network control message;
a terminal entering a cell surrounding a base station is set to the highest available limit value;
the limit value set for a given terminal is set higher as the detected communication condition is determined to be less sufficient;
the limit value set for a given terminal is set lower as the detected communication condition is determined to be more sufficient;
the limit value for a transmitting power set for a given terminal is set higher as a frequency band related to the limit value is determined to be further away from a forbidden frequency band;
the limit value for a transmitting power set for a given terminal is set lower as a frequency band related to the limit value is determined to be closer to a forbidden frequency band;
at least one, or more of means for transmitting, means for selecting, means for setting, means for detecting, means for receiving, means for allocating, means for delaying, means for monitoring, means for changing, means for configuring, means for acknowledging and the apparatus is implemented as a chipset or module.
According to an example of the present invention, in a fifth aspect, this object is for example achieved by a system comprising:
an apparatus according to the above third aspect; and
an apparatus according to the above fourth aspect.
According to an example of the present invention, in a sixth aspect, this object is for example achieved by a computer program product comprising code means for performing a method according to the above first and second aspects when run on a processing means or module.
According to an example of the present invention, in a seventh aspect, this object is for example achieved by a data structure comprising:
a network control message comprising a plurality of limit values, each of the limit values being related to a first network communication parameter in relation to a second network communication parameter and being individually set for a selected terminal.
According to further refinements of the example of the present invention as defined under the above seventh aspect,
the network control message is a radio resource control system information message;
the radio resource control system information message is transmitted via a physical downlink shared channel;
the radio resource control system information message refers to configuration parameters for power control and resource allocation for one of a physical uplink shared channel, a physical uplink control channel and a sounding reference symbol channel;
the limit values are accommodated in at least one system information block;
the at least one system information block is constituted by at least one of a system information block type 5, a system information block type 5bis, and a system information block type 6.
In this connection, examples of the present invention enable one or more of the following:
Coping with different types of coexistence challenges on the receive side and/or the transmit side, e.g. both of a base station (BS) and a terminal or user equipment (UE);
Coping with situations where the maximum UE transmit power of the UE may have to be limited, and where the limit of the maximum UE transmit power may vary over position and width of allocations inside a frequency band, or regionally inside a nation-wide network;
Providing a solution which allows for avoiding static solutions and limitation of coverage;
Providing a solution to avoid increased guard bands between conflicting technologies, thus extending the useable bandwidth and spectral efficiency;
Enabling the allocation of otherwise non-allocatable spectrum portions;
Enabling a safe method for limiting the transmit power of specific UEs to a value lower than broadcasted Pmax valid for the complete cell;
Guaranteeing that these selected UEs do not exceed the desired transmit power value lower than Pmax, thus preventing reduction of the performance of all UEs in the cell including UEs at the cell border;
Enabling safe power control at the TTI resolution level;
Preventing that UE uses full power headroom for path loss compensation (despite biasing from filtering and averaging) e.g. in case a UE is close to the cell edge or in case of sudden shadowing;
Taking into account latency in applying e.g. Pmax2 as maximum transmit power, and taking into account minimum and maximum possible allocation limits depending on Power used and the sub-band used.
Examples of the present invention are described herein below with reference to the accompanying drawings, in which:
Examples of the present invention are described herein below by way of example with reference to the accompanying drawings.
It is to be noted that for this description, the terms “RRC SYSTEM INFORMATION message; transmitting power; and frequency band” are examples for “network control message; first network communication parameter; and second network communication parameter”, respectively, without restricting the latter-named terms to the special technical or implementation details imposed to the first-named terms.
As shown in
The “aggressor technology” may correspond e.g. to LTE Rel-8 or another orthogonal frequency division multiple access (OFDMA) based technology which may allow for partial UL allocations localized in frequency dimension. As a consequence, UEs being allocated in the spectrum portion denoted by the dashed circle/hatched box may transmit e.g. with a higher output power (denoted by the hatched box, i.e. those UEs are, in the frequency domain, far away from the “victim technology”) than the UEs allocated in the spectrum portion denoted by the solid circle/black box. It is to be noted that in this example, the spectrum has been split up into two parts. However, this only serves for simplicity, to which descriptive simplification the examples of the present invention are not to be restricted to; generally, the spectrum may be split into N parts, where N may be as large as reasonable with respect e.g. to UL allocation granularity and/or cell range.
As mentioned above, the min-function in the UL power control formula (see equation (1) above) rules out any output power (calculated by the UE) larger than Pmax. Pmax may be used to generally limit the maximum UE transmit power for the near-far problem or tough adjacent channel leakage requirements.
However, limiting the maximum transmit power of all UEs such that the UEs situated in the solid circle do not interfere with the “victim technology”, may limit the throughput and cell range as shown also in
Hence, a UE-specific limitation of the maximum transmit power may be applicable. For example, a UE under good radio conditions and small path loss may be allocated in the spectrum portion denoted by the solid circle/black box when staying below a rather low limit of transmit power. A UE with high path loss or poor conditions should not be limited (at all or too much) in transmit power, and may be allocated in the spectrum portion denoted by the dashed circle/hatched box.
Hence, there is a conjunction e.g. between power control (PC) and allocation on certain parts of the frequency spectrum. Such an allocation may be handled by a scheduler.
The above equation (1) specifies the UE transmit power for PUSCH. However, the examples of the present invention are not to be limited to PUSCH, but are also applicable to PUCCH and SRS that may use the same parameter Pmax.
As for
In an optional step S1-1, e.g. the BS 202 may perform detecting a communication condition (such as “good” or “bad” e.g. according to shadowing, path loss etc.) of each one of the plurality of terminals UE1 to UEN 201. Furthermore, the detecting performed in step S1-1 may further comprise, in an optional step S1-0, receiving a power headroom report, a received signal strength indication (e.g. RSSI) or a timing advance information. The power headroom report, the received signal strength indication (e.g. RSSI) or the timing advance information may have been transmitted e.g. by each one of the UE(s) 201 in an optional step S2-0.
Then, in an optional step S1-2, e.g. the BS 202 may perform setting a plurality of limit values (e.g. for transmission power) based on the detected communication condition of the plurality of terminals.
Further, in an optional step S1-3, e.g. the BS 202 may perform selecting one or more out of the plurality of terminals UE(s) 201 based on the detected communication condition.
Then, in step S1-4, e.g. the BS 202 may perform transmitting, to each selected one of the plurality of terminals UE(s) 201, a network control message (e.g. RRC SYSTEM INFORMATION msg) comprising the plurality of limit values (e.g. Pmax2, . . . , PmaxN), each of the limit values being related to a first network communication parameter (e.g. transmitting power of the respective UE) in relation to a second network communication parameter (e.g. frequency band to be used by the respective UE) and being individually set for the selected terminal, based on the detected communication condition of each one of the plurality of terminals.
Furthermore, in an optional step S1-5, e.g. the BS 202 may perform allocating a communication resource for the plurality of terminals based on the detected communication condition. Furthermore, the allocating performed in step S1-5 may further comprise, in an optional step S1-6, delaying the allocation.
Moreover, in an optional step S1-7, e.g. the BS 202 may perform monitoring the detected communication condition and may also perform, in an optional step S1-8, if the monitored communication condition has changed, changing the plurality of set limit values according to the changed communication condition.
In response to the above step S1-4, e.g. the selected UE(s) 201 may perform, in an optional step S2-1, receiving the network control message from the base station BS 202.
Then, in step S2-2, e.g. the or each UE 201 selected may perform configuring the terminal (e.g. the or each selected UE 201) according to the first network communication parameter (e.g. transmitting power of the UE 201) in relation to the second network communication parameter (e.g. frequency band to be used by the UE 201) based on the received network control message comprising the plurality of limit values, each of the limit values being related to the first network communication parameter in relation to the second network communication parameter and being individually set for the terminal.
In an optional step S2-3, e.g. the or each UE 201 selected may perform acknowledging successful receipt of the network control message to the base station BS 202.
According to further developments of the above methods according to an example of the present invention, the network control message may be a radio resource control system information message, and the radio resource control system information message may be transmitted via the physical Downlink shared channel (PDSCH). Furthermore, the set limit values may be used in an UL direction from the terminals to the base station. Still further, the first network communication parameter may be a transmitting power of each one of the plurality of terminals, and the second network communication parameter may be a frequency band to be used by each one of the plurality of terminals. Furthermore, one of the limit values (e.g. Pmax1) may be broadcast to each one of the plurality of terminals, while the remaining limit values may be set and transmitted individually in each network control message.
In addition, as implementation possibilities for the methods according to an example of the present invention, a terminal entering a cell surrounding a base station may be set to the highest available limit value. Furthermore, the limit value set for a given terminal may be set higher/lower as the detected communication condition is determined to be less/more sufficient. And, the limit value for a transmitting power set for a given terminal may be set higher/lower as a frequency band related to the limit value is determined to be further away from/to be closer to a forbidden frequency band.
The UE 201 may comprise a CPU (or core functionality CF) 2011, a memory 2012, an optional transmitter (or means for transmitting) 2013, an optional receiver (or means for receiving) 2014, a configurator (or means for configuring) 2015 and an optional acknowledger (or means for acknowledging) 2016.
Further, the BS 202 may comprise a CPU (or core functionality CF) 2021, a memory 2022, a transmitter (or means for transmitting) 2023, an optional receiver (or means for receiving) 2024, an optional detector (or means for detecting) 2025, an optional setter (or means for setting) 2026, an optional selector (or means for selecting) 2027, an optional allocator (or means for allocating) 2028, an optional delayer (or means for delaying) 2029, an optional monitor (or means for monitoring) 20210 and an optional changer (or means for changing) 20211.
As indicated by the dashed extension of the functional blocks of the CPUs 2011, 2021, the means for transmitting 2013, the means for receiving 2014, the means for configuring 2015 and the means for acknowledging 2016 of the or each UE 201 as well as the means for transmitting 2023, the means for receiving 2024, the means for detecting 2025, the means for setting 2026, the means for selecting 2027, the means for allocating 2028, the means for delaying 2029, the means for monitoring 20210 and the means for changing 20211 of the BS 202 may be functionalities running on the CPUs 2011, 2021 of the UE(s) 201 and BS 202, respectively, or may alternatively be separate functional entities or means.
The CPUs 20x1 (wherein x=1 and 2) may respectively be configured to process various data inputs and to control the functions of the memories 20x2, the means for transmitting 202x3 and the means for receiving 20x4 (and the means for configuring 2015 and the means for acknowledging 2016 of the or each UE 201 as well as the means for detecting 2025, the means for setting 2026, the means for selecting 2027, the means for allocating 2028, the means for delaying 2029, the means for monitoring 20210 and the means for changing 20211 of the BS 202). The memories 20x2 may serve e.g. for storing code means for carrying out e.g. the methods according to the first and second examples of the present invention, when run e.g. on the CPUs 20x1. It is to be noted that the means for transmitting 20x3 and the means for receiving 20x4 may alternatively be provided as respective integral transceivers. It is further to be noted that the transmitters/receivers may be implemented i) as physical transmitters/receivers for transceiving e.g. via the air interface (e.g. in case of transmitting between the UEs 201 and the BS 202), ii) as routing entities e.g. for transmitting/receiving data packets e.g. in a PS (packet switched) network (e.g. between the BS 202 and another internal network entity (not shown) when disposed as separate network entities), iii) as functionalities for writing/reading information into/from a given memory area (e.g. in case of shared/common CPUs or memories e.g. of the BS 202 and the another internal network entity when disposed as an integral network entity), or iv) as any suitable combination of i) to iii).
Optionally, e.g. the means for detecting 2025 of the BS 202 may perform detecting a communication condition (such as “good” or “bad” e.g. according to shadowing, path loss etc.) of each one of the plurality of terminals UE1 to UEN 201. Furthermore, the means for detecting 2025 may further comprise means for receiving 2024 of a power headroom report, a received signal strength indication (e.g. RSSI) or a timing advance information. Optionally, the power headroom report, the received signal strength indication (e.g. RSSI) or the timing advance information may have been transmitted e.g. by means for transmitting 2013 of the or each UE 201.
Then, optionally, e.g. the means for setting 2026 of the BS 202 may perform setting a plurality of limit values (e.g. for transmission power) based on the detected communication condition of the plurality of terminals.
Further optionally, e.g. the means for selecting 2027 of the BS 202 may perform selecting one or more out of the plurality of terminals UE(s) 201 based on the detected communication condition.
Then, e.g. the means for transmitting 2023 of the BS 202 may perform transmitting, to each selected one of the plurality of terminals UE(s) 201, a network control message (e.g. RRC SYSTEM INFORMATION msg) comprising the plurality of limit values (e.g. Pmax2, . . . , PmaxN), each of the limit values being related to a first network communication parameter (e.g. transmitting power of the respective UE) in relation to a second network communication parameter (e.g. frequency band to be used by the respective UE) and being individually set for the selected terminal, based on the detected communication condition of each one of the plurality of terminals.
Furthermore, optionally, e.g. the means for allocating 2028 of the BS 202 may perform allocating a communication resource for the plurality of terminals based on the detected communication condition. Furthermore, the means for allocating 2028 may further comprise means for delaying 2029 for delaying the allocation.
Moreover, optionally, e.g. the means for monitoring 20210 of the BS 202 may perform monitoring the detected communication condition, and may also comprise the means for changing 20211 for changing, if the monitored communication condition has changed, the plurality of set limit values according to the changed communication condition.
In response to the transmitting performed by the means for transmitting 2023 of the BS 202, e.g. means for receiving 2014 of the selected UE(s) 201 may perform receiving the network control message from the base station BS 202.
Then, e.g. the means for configuring 2015 of the or each UE 201 selected may perform configuring the terminal (e.g. the or each selected UE 201) according to the first network communication parameter (e.g. transmitting power of the UE 201) in relation to the second network communication parameter (e.g. frequency band to be used by the UE 201) based on the received network control message comprising the plurality of limit values, each of the limit values being related to the first network communication parameter in relation to the second network communication parameter and being individually set for the terminal.
Optionally, e.g. the means for acknowledging 2016 of the or each UE 201 selected may perform acknowledging successful receipt of the network control message to the base station BS 202. To this end, the means for acknowledging 2016 may make use of the means for transmitting 2013 of the UE 201 in question.
According to further developments of the above apparatuses according to an example of the present invention, the network control message may be a radio resource control system information message, and the radio resource control system information message may be transmitted via a physical downlink shared channel (PDSCH The radio resource control system information message refers to configuration parameters for power control and resource allocation for the PUSCH, PUCCH, and SRS channels. Furthermore, the set power limit values may be used in an UL direction from the terminals to the base station. Still further, the first network communication parameter may be a transmitting power of each one of the plurality of terminals, and the second network communication parameter may be a frequency band to be used by each one of the plurality of terminals. Furthermore, one of the limit values (e.g. Pmax1) may be broadcast to each one of the plurality of terminals, while the remaining limit values may be set and transmitted individually in each network control message.
In addition, as implementation possibilities for the apparatuses according to an example of the present invention, a terminal entering a cell surrounding a base station may be set to the highest available limit value. Furthermore, the limit value set for a given terminal may be set higher/lower as the detected communication condition is determined to be less/more sufficient. And, the limit value for a transmitting power set for a given terminal may be set higher/lower as a frequency band related to the limit value is determined to be further away from/to be closer to a forbidden frequency band.
Furthermore, at least one of, or more of means for transmitting 2013, 2023, means for selecting 2027, means for setting 2026, means for detecting 2025, means for receiving 2014, 2024, means for allocating 2028, means for delaying 2029, means for monitoring 20210, means for changing 20211, means for configuring 2015, means for acknowledging 2016, the UE(s) 201 and/or the BS 202, or the respective functionalities carried out, may be implemented as a chipset or module.
Finally, the present invention also relates to a system which may comprise at least one UE 201 and a BS 202 according to the above-described example of the present invention.
Still further, as shown in
That is, as shown in
According to further developments of the example, the data structure may be modified such that the network control message may be a radio resource control system information message 301. Further, the radio resource control system information message 301 may be transmitted via a physical downlink shared channel (PDSCH). The radio resource control system information message refers to configuration parameters for power control and resource allocation for the PUSCH, PUCCH, and SRS channels. Still further, the limit values may be accommodated in at least one system information block 3011, 3012, 3013, and the at least one system information block may be constituted by a system information block type 5, a system information block type 5bis, and/or a system information block type 6.
Without being restricted to the details following in this section, the embodiment of the present invention may be summarized as follows:
The invention may consist in a novel structured power control scheme which allows for safely setting UE-specific (different) maximum UE transmit power limits depending on frequency allocation. Power limits shall be given in absolute numbers or given as relative (differential numbers) per frequency sub-band. On top of this, power control and scheduler work together to guarantee the power and allocation limits per sub-band.
Sub-band specific power levels shall be either broadcast or better submitted resource efficient via dedicated RRC messages to only those UEs which are concerned.
The basic solution may consist of substituting the Uplink power control broadcast information in the SystemInformationBlock for a single maximum UE transmit power limit Pmax with a finite set of maximum UE transmit power limits in dBm {Pmax1, Pmax2, . . . , PmaxN}.
For simplicity reasons, the novel power control scheme is explained using two maximum power levels {Pmax1, Pmax2} only:
1. The cell is configured with 2 different maximum UE transmit power limits {Pmax1, Pmax2}. Assumption is that Pmax1 is broadcast and Pmax2 is UE specifically submitted by dedicated message.
2. A UE entering the LTE cell has received broadcast and sets Pmax=Pmax1, for the example in
3. A UE entering the LTE cell is never allocated in Spectrum Portion 2 implying the lower maximum power limit Pmax2. This provides good coverage for cell edge users. Allocation is handled by scheduler.
4. From the power headroom reports or other means like RSSI or Timing Advance, the base station calculates which UEs are in good conditions and will survive a tough maximum power limit (Pmax2) and which UEs are in bad conditions and should have a relaxed maximum power limit (Pmax1).
5. The base station signals Pmax2<Pmax1 over RRC layer to UEs in good shape only.
6. The good shape UE shall use Pmax=min {Pmax1, Pmax2}=Pmax2 in its power control formulae for PUSCH, PUCCH, and SRS.
7. The UE is only connected if RRC message was successful. As an alternative implementation, the UE might acknowledge the new RRC value setting.
8. After a defined delay, the base station scheduler can allocate UEs in good shape now also in spectrum Portion 2 as the UE will apply Pmax2 in its power control formula and hence not interfere with the coexisting technology. The delay takes into account latency in applying Pmax2 as maximum transmit power. The scheduler takes into account minimum and maximum possible allocation limits depending on Power used and the sub-band used.
9. The base station constantly monitors the status of the UEs. As soon as a UE which has been in good shape sees worse conditions, the base station signals Pmax1 over RRC layer and instantaneously allocates the UE in spectrum Portion 1. Triggering points to identify worse conditions might be e.g. evaluation of power headroom reports, RSSI measurements or Timing Advance information.
In other words, the steps of the invention may be:
Introduction of new UE and allocation specific parameters Pmax1, . . . , PmaxN to be configured by the operator.
Sub-band specific power levels are either broadcast or submitted via dedicated RRC.
Maximum transmit power applied by the UE to be defined by Pmax=min {Pmax1, . . . , PmaxN}.
Identification of UEs that are suited for operation at reduced transmit power.
Separation of the frequency spectrum into two or more parts (up to N bands).
In conjunction to the power also minimum and maximum allocation limits can be defined per sub-band (up to N bands).
Dedicated signaling of a new maximum transmit power to identified UEs depending on preferred allocation sub-band.
In case of resource bottlenecks allocation of resources to identified UEs from the band adjacent to coexistence spectrum by using lower maximum transmit power.
In wireless networks characterized by coexistence problems with other wireless technologies the whole frequency spectrum can still be utilized. Interference is avoided by reducing the maximum transmit power for critical frequencies to a lower value signaled to the UE via RRC.
Continuous monitoring and identification of UEs that are no longer suited for operation at reduced maximum transmit power. RRC signaling of new maximum transmit power (typically identical to broadcast value).
The reduced power commanded shall be applied to uplink and potentially also for downlink.
This invention provides a flexible mechanism to handle coexistence situations with other wireless technologies.
For the purpose of the present invention as described herein above, it should be noted that
an access technology may be any technology by means of which a user equipment can access an access network (or base station, respectively). Any present or future technology, such as WiMAX (Worldwide Interoperability for Microwave Access) or WLAN (Wireless Local Access Network), BlueTooth, Infrared, and the like may be used; although the above technologies are mostly wireless access technologies, e.g. in different radio spectra, access technology in the sense of the present invention may also imply wirebound technologies, e.g. IP based access technologies like cable networks or fixed line.
a network may be any device, unit or means by which a station entity or other user equipment may connect to and/or utilize services offered by the access network; such services include, among others, data and/or (audio-) visual communication, data download etc.;
generally, the present invention may be applicable in those network/user equipment environments relying on a data packet based transmission scheme according to which data are transmitted in data packets and which are, for example, based on the Internet Protocol IP. The present invention is, however, not limited thereto, and any other present or future IP or mobile IP (MIP) version, or, more generally, a protocol following similar principles as (M) IPv4/6, is also applicable;
a user equipment may be any device, unit or means by which a system user may experience services from an access network;
method steps likely to be implemented as software code portions and being run using a processor at a network element or terminal (as examples of devices, apparatuses and/or modules thereof, or as examples of entities including apparatuses and/or modules therefore), are software code independent and can be specified using any known or future developed programming language as long as the functionality defined by the method steps is preserved;
generally, any method step is suitable to be implemented as software or by hardware without changing the idea of the invention in terms of the functionality implemented;
method steps and/or devices, units or means likely to be implemented as hardware components at the above-defined apparatuses, or any module(s) thereof, are hardware independent and can be implemented using any known or future developed hardware technology or any hybrids of these, such as MOS (Metal Oxide Semiconductor), CMOS (Complementary MOS), BiMOS (Bipolar MOS), BiCMOS (Bipolar CMOS), ECL (Emitter Coupled Logic), TTL (Transistor-Transistor Logic), etc., using for example ASIC (Application Specific IC (Integrated Circuit)) components, FPGA (Field-programmable Gate Arrays) components, CPLD (Complex Programmable Logic Device) components or DSP (Digital Signal Processor) components; in addition, any method steps and/or devices, units or means likely to be implemented as software components may alternatively be based on any security architecture capable e.g. of authentication, authorization, keying and/or traffic protection;
devices, units or means (e.g. the above-defined apparatuses, or any one of their respective means) can be implemented as individual devices, units or means, but this does not exclude that they are implemented in a distributed fashion throughout the system, as long as the functionality of the device, unit or means is preserved;
an apparatus may be represented by a semiconductor chip, a chipset, or a (hardware) module comprising such chip or chipset; this, however, does not exclude the possibility that a functionality of an apparatus or module, instead of being hardware implemented, be implemented as software in a (software) module such as a computer program or a computer program product comprising executable software code portions for execution/being run on a processor;
a device may be regarded as an apparatus or as an assembly of more than one apparatus, whether functionally in cooperation with each other or functionally independently of each other but in a same device housing, for example.
Although the present invention has been described herein before with reference to particular embodiments thereof, the present invention is not limited thereto and various modification can be made thereto.
For ease of clarity, the following table provides a survey of the abbreviations partially used in the above description. It is to be noted that an “s” following an abbreviation represents the plural of that abbreviation, e.g. “UEs” represents “user equipments”.
| Number | Date | Country | Kind |
|---|---|---|---|
| 08168217.1 | Nov 2008 | EP | regional |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP2009/064533 | 11/3/2009 | WO | 00 | 6/10/2011 |
