CN103079211A - Heterogeneous network interference coordination method on basis of carrier aggregation - Google Patents

Abstract

The invention relates to a heterogeneous network interference coordination method on the basis of carrier aggregation. Due to consideration on that interference to Pico edge users is the most serious, and thus, the carrier aggregation characteristic is utilized to enable macro station not to send a control signaling on control channels of part of composition carriers and according to scheduled user information with the worst SINR (Signal Interference Noise Ratio) in the Pico edge users, transmission power of the macro station on data channels of the part of composition carriers is reduced, so that interference of the macro station to the control channels and the data channels of the Pico edge users is reduced to a great degree. Moreover, due to consideration on that reduction of the transmission power of the macro station on part of composition carriers possibly causes reduction of throughput of the macro station, by a cost function consisting of throughput loss of macro users and a throughput gain of the Pico edge users, the data channel transmission power of the macro station on the composition carriers which provide interference protection is determined, so that while the throughput of the Pico edge users is improved, the throughput loss of the macro station is reduced and the total throughput of a system is promoted.

Description

A kind of heterogeneous network disturbance coordination method based on carrier aggregation

Technical field

The invention belongs to the wireless access technology field in the mobile communication, relate in a kind of wireless communication system the heterogeneous network dl interference coordination approach based on carrier aggregation technology.

Background technology

For satisfying growing covering and capacity requirement, LTE-A(Long Term Evolution-Advanced) introduces heterogeneous network, slightly stand by covering basic deploy Pico(at grand station), Femto(femto station), the Relay(relay station) etc. the low-power small station, user and basic distance between sites further, improve power system capacity and covering power, but meanwhile brought serious interference problem.In addition, for load balancing and further be grand station load sharing, its descending coverage is expanded by power bias in the small station, but this cell range expansion has further increased the weight of presence of intercell interference, is positioned at the interference that cell range expansion area intra domain user is subject to especially serious.Carrier aggregation is another key technology of LTE-A system, provides larger bandwidth by a plurality of continuous or discrete one-tenth sub-carriers in the aggregated spectrum for the user, and by avoiding presence of intercell interference for neighbor cell allocation heterogeneity carrier wave.Disturbing between the grand station-Pico of support carrier aggregation needs to solve at first.Existing based on carrier aggregation the heterogeneous network interference coordination schemes or only consider control channel interference or data channel disturbs, perhaps some becomes the transmitted power of sub-carrier to obtain the raising of Pico edge customer throughput by reducing grand station, reduces grand station and the overall system loss of throughput of bringing and ignore transmitted power.Therefore the present invention proposes a kind of new grand station based on carrier aggregation-Pico heterogeneous network disturbance coordination method, can avoid simultaneously control channel and data channel to disturb, and when improving Pico edge customer throughput, guarantee grand station throughput and overall system throughput.

Summary of the invention

Technical problem: the objective of the invention is to propose a kind of control channel and data channel interference that the small station edge customer is subject to that solve, and in the interference that reduction small station edge customer is subject to, can reduce the loss of throughput at grand station, the heterogeneous network disturbance coordination method based on carrier aggregation that the minimizing overall system performance descends.

Technical scheme: the heterogeneous network disturbance coordination method based on carrier aggregation of the present invention comprises the steps:

Initialization base station and user: the sub-carrier that may be configured as of supposing each grand station or slight station is gathered identical, be designated as K, each becomes sub-carrier that R Resource Block arranged, each time frame comprises control channel and data channel, user's set in the overlay area, grand station is designated as U, and each user u has a target Signal to Interference plus Noise Ratio γ ^Target, in order to guarantee user's service quality;

The first step: the user determines Serving cell and user type: the Reference Signal Received Power that the user receives from grand station is RSRP _{U, M}, be RSRP from the Reference Signal Received Power at slight station _{U, P}, select its Serving cell according to max (RSRP+bias) criterion, and determine that its user type is grand station user, slight stand central user or slightly stand edge customer, with the most weak slight station Reference Signal Received Power RSRP _{U, P}The poorest slight station edge customer;

Second step: base station composition allocation of carriers mode is set: grand station side, the control channel of part basic ingredient carrier wave and data channel are all with full power transmissions, another part becomes the control channel of sub-carrier not send control signaling, data channel is by the dynamic-configuration low-power, for the user that slightly stands provides interference protection; Slight station side, the composition carrier Control channel of interference-free protection only is being disturbed the control channel of protecting into sub-carrier when not enough, for the central user of slightly standing provides control channel, the data channel of the one-tenth sub-carrier of interference-free protection can be used for all users, the composition carrier Control channel that is disturbed protection can be used for all users, its data channel Priority Service edge customer of slightly standing;

The 3rd step: determine the scheduled user: each time slot scheduling, each base station is according to its service-user information and stride the carrier wave proportional fair dispatching method and dispatch for each becomes each Resource Block r selection of sub-carrier k to satisfy the user that composition allocation of carriers mode requires;

The 4th step: calculate the slightly patient grand station of user, station maximum transmit power: according to the schedule information that the 3rd step was determined, if there is no Signal to Interference plus Noise Ratio can't satisfy the slightly station edge customer that is scheduled of business demand, namely

Then entered for the 7th step, otherwise to the control indication of slight station feedback power, the station is according to the information of the poorest slight station edge customer slightly, calculates this user institute patient from the maximum interference I at all grand stations on every side ^Max,

$I^{\max }=\frac{P_{u,P,k}}{{\mathrm{\γ}}^{t\arg \mathrm{et}}}-N_0---\left(1\right)$

Wherein, k is the used one-tenth sub-carrier of this user, P _{U, P, k}Be power, the N from the carrier wave k at slight station that receives ₀Be noise power;

The interference I that recycling other grand stations except grand station, place, slight station produce _{M '}And channel gain G between the grand station of this user and place _{U, M}, calculating is providing the one-tenth sub-carrier CC of interference protection _pOn, this user institute patient grand station maximum transmit power

$P_{M,{\mathrm{CC}}_p}=\frac{I^{\max }-I_{M^{\′}}}{G_{u,M}}---\left(2\right);$

The 5th step: according to the systematic cost p after the control of following formula rated output, after guaranteeing that grand station reduces power, its loss of throughput can be not excessive, and the systematic cost function p after the power control is defined as grand station and reduces before and after the power edge customer throughput gain of slightly standing

With grand station loss of throughput

Poor, that is:

$p={\mathrm{Thr}}_{P\_\mathrm{edge}}^{\mathrm{Gain}}-{\mathrm{Thr}}_M^{\mathrm{Loss}}---\left(3\right);$

The 6th step: determine that grand station provides interference protection to become the transmitted power of sub-carrier: according to the systematic cost p after the power control that calculates; if the systematic cost p after the power control 〉=0; show grand station reduce power be the gain that brings of Pico edge customer greater than the grand user's in station loss own, then will

Entered for the 7th step after the transmitted power that provides interference protection to become sub-carrier as grand station, otherwise, show that grand station loss of throughput is excessive, need to improve

To guarantee grand station throughput, at this moment get

As providing interference protection to become the transmitted power of sub-carrier and getting back to for the 5th step, wherein dBm is the power unit milliwatt;

The 7th step: finish this flow process.

Beneficial effect: the present invention compared with prior art has the following advantages:

By forbidding that the grand part that stands in becomes on the sub-carrier to send control signaling, and when can't being met, the Pico edge customer service quality that is scheduled for reduces the data channel transmitted power that this part becomes sub-carrier, can effectively avoid the interference to the Pico edge customer, and by becoming in this section the edge customer of slightly standing of priority scheduling on the sub-carrier further to reduce the interference that slight station edge customer is subject to.Thereby improve Pico edge customer throughput.Simultaneously, calculate by avoiding the excessive cost of grand station user throughput loss, so that the loss of grand station always is not more than the gain of Pico edge customer, has effectively guaranteed grand station throughput, and the overall system throughput is improved.

Description of drawings

Fig. 1 is the heterogeneous network disturbance coordination method entire flow based on carrier aggregation of the present invention.

Embodiment

Heterogeneous network disturbance coordination method based on carrier aggregation of the present invention, at first, the user in the system selects its Serving cell according to max (RSRP+bias) criterion, and determines its user type; Then be arranged to the sub-carrier method of salary distribution for the base station; Then, in each time slot scheduling, determine that according to striding carrier wave Proportional Fair scheme the user who is scheduled gathers; Whether next step exists the SINR(Signal to Interference plus Noise Ratio according in the scheduled user set) excessively poor Pico(stands slightly) edge customer judges whether to carry out power control, and calculate the poorest user institute patient grand station maximum transmit power; Then the systematic cost after the transmitted power rated output that provides interference protection to become sub-carrier with this transmitted power as grand station is controlled; If grand station loss of throughput then increases this transmitted power greater than Pico edge customer throughput gain, recomputate the systematic cost after power is controlled, until grand station loss of throughput is not more than Pico edge customer throughput gain; At last the power that calculates being made as the grand station of current time slots provides interference protection to become the transmitted power of sub-carrier.Enter next time slot scheduling after finishing.

Take the LTE-A system as example provides a kind of embodiment, comprise the steps:

Initialization: suppose that each grand station or Pico(stand slightly) the sub-carrier that may be configured as is gathered identical, be designated as K, each becomes sub-carrier that R Resource Block arranged, each time frame comprises control channel and data channel, user's set in the overlay area, grand station is designated as U, and each user u has a target Signal to Interference plus Noise Ratio γ ^Target, in order to guarantee user's service quality;

The first step: the user determines Serving cell and user type.The Reference Signal Received Power that the user receives from grand station is RSRP _{U, M}, be RSRP from the Reference Signal Received Power of Pico _{U, P}, select its Serving cell according to max (RSRP+bias) criterion, and determine that its user type is grand station user, Pico central user or Pico edge customer, with the most weak slight station Reference Signal Received Power RSRP _{U, P}The poorest slight station edge customer.

Second step: base station composition allocation of carriers mode is set.Grand station side, the control channel of a part of basic ingredient carrier wave and data channel are all with full power transmissions; Another part becomes the control channel of sub-carrier not send control signaling, and data channel is by the dynamic-configuration low-power, for Pico user provides interference protection.Pico side, the composition carrier Control channel of interference-free protection only are being disturbed the control channel of protecting into sub-carrier when not enough, and for the Pico central user provides control channel, the data channel of the one-tenth sub-carrier of interference-free protection can be used for all users; The composition carrier Control channel that is disturbed protection can be used for all users, its data channel Priority Service Pico edge customer.

The 3rd step: determine the scheduled user.Each time slot scheduling, each base station according to its service-user information with stride the carrier wave proportional fair dispatching method and become sub-carrier k(k ∈ K for each) each Resource Block r(r ∈ R) select to satisfy the user that composition allocation of carriers mode requires and dispatch.

The 4th step: calculate the patient grand station of Pico user maximum transmit power.According to schedule information, if there is no SINR(Signal to Interference plus Noise Ratio) can't satisfy the Pico edge customer that is scheduled of business demand, namely

Then entered for the 7th step, otherwise to the control indication of Pico feedback power, Pico is according to the poorest Pico edge customer information, calculates this user institute patient from the maximum interference I at all grand stations on every side ^Max,

$I^{\max }=\frac{P_{u,P,k}}{{\mathrm{\γ}}^{t\arg \mathrm{et}}}-N_0---\left(1\right)$

Wherein, k is the used one-tenth sub-carrier of this user, P _{U, P, k}Be power, the N from the carrier wave k at slight station that receives ₀Be noise power;

Recycling except grand station, Pico place, the interference I that other grand stations produce _{M '}And channel gain G between the grand station of this user and place _{U, M}, calculating is providing the one-tenth sub-carrier CC of interference protection _pOn, this user institute patient grand station maximum transmit power

$P_{M,{\mathrm{CC}}_p}=\frac{I^{\max }-I_{M^{\′}}}{G_{u,M}}---\left(2\right)$

The 5th step: according to the systematic cost after the control of following formula rated output, after guaranteeing that grand station reduces power, its loss of throughput can be not excessive, and the systematic cost function p after the power control is defined as grand station and reduces before and after the power Pico edge customer throughput gain

With grand station loss of throughput

Poor, that is:

$p={\mathrm{Thr}}_{P\_\mathrm{edge}}^{\mathrm{Gain}}-{\mathrm{Thr}}_M^{\mathrm{Loss}}---\left(3\right)$

The 6th step: determine that grand station provides interference protection to become the transmitted power of sub-carrier.According to the systematic cost p after the control of the power that calculates, if p 〉=0, show grand station reduce power be the gain that brings of Pico edge customer greater than the grand user's in station loss own, then will

Entered for the 7th step after the transmitted power that provides interference protection to become sub-carrier as grand station.Otherwise, show that grand station loss of throughput is excessive, need to improve

To guarantee grand station throughput, at this moment get

As providing interference protection to become the transmitted power of sub-carrier and getting back to for the 5th step, wherein dBm is the power unit milliwatt, stops when namely Pico edge customer throughput gain is greater than grand station loss of throughput, will this moment Provide interference protection to become the transmitted power of sub-carrier as grand station.

Claims (1)

1. the heterogeneous network disturbance coordination method based on carrier aggregation is characterized in that, the method may further comprise the steps:

Initialization base station and user: the sub-carrier that may be configured as of supposing each grand station or slight station is gathered identical, be designated as K, each becomes sub-carrier that R Resource Block arranged, each time frame comprises control channel and data channel, user's set in the overlay area, grand station is designated as U, and each user u has a target Signal to Interference plus Noise Ratio γ ^Target, in order to guarantee user's service quality;

The first step: the user determines Serving cell and user type: the Reference Signal Received Power that the user receives from grand station is RSRP _{U, M}, be RSRP from the Reference Signal Received Power at slight station _{U, P}, select its Serving cell according to max (RSRP+bias) criterion, and determine that its user type is grand station user, slight stand central user or slightly stand edge customer, with the most weak slight station Reference Signal Received Power RSRP _{U, P}The poorest slight station edge customer;

Second step: base station composition allocation of carriers mode is set: grand station side, the control channel of part basic ingredient carrier wave and data channel are all with full power transmissions, another part becomes the control channel of sub-carrier not send control signaling, data channel is by the dynamic-configuration low-power, for the user that slightly stands provides interference protection; Slight station side, the composition carrier Control channel of interference-free protection only is being disturbed the control channel of protecting into sub-carrier when not enough, for the central user of slightly standing provides control channel, the data channel of the one-tenth sub-carrier of interference-free protection can be used for all users, the composition carrier Control channel that is disturbed protection can be used for all users, its data channel Priority Service edge customer of slightly standing;

The 3rd step: determine the scheduled user: each time slot scheduling, each base station is according to its service-user information and stride the carrier wave proportional fair dispatching method and dispatch for each becomes each Resource Block r selection of sub-carrier k to satisfy the user that composition allocation of carriers mode requires;

The 4th step: calculate the slightly patient grand station of user, station maximum transmit power: according to the schedule information that the 3rd step was determined, if there is no Signal to Interference plus Noise Ratio can't satisfy the slightly station edge customer that is scheduled of business demand, namely

Then entered for the 7th step, otherwise to the control indication of slight station feedback power, the station is according to the information of the poorest slight station edge customer slightly, calculates this user institute patient from the maximum interference I at all grand stations on every side ^Max,

$I^{\max }=\frac{P_{u,P,k}}{{\mathrm{\γ}}^{t\arg \mathrm{et}}}-N_0---\left(1\right)$

Wherein, k is the used one-tenth sub-carrier of this user, P _{U, p, k}Be power, the N from the carrier wave k at slight station that receives ₀Be noise power;

The interference I that recycling other grand stations except grand station, place, slight station produce _M, and channel gain G between the grand station of this user and place _{U, M}, calculating is providing the one-tenth sub-carrier CC of interference protection _pOn, this user institute patient grand station maximum transmit power

$P_{M,{\mathrm{CC}}_p}=\frac{I^{\max }-I_{M^{\′}}}{G_{u,M}}---\left(2\right);$

The 5th step: according to the systematic cost p after the control of following formula rated output, after guaranteeing that grand station reduces power, its loss of throughput can be not excessive, and the cost function p of system is defined as grand station and reduces before and after the power edge customer throughput gain of slightly standing

With grand station loss of throughput Poor, that is:

$p={\mathrm{Thr}}_{P\_\mathrm{edge}}^{\mathrm{Gain}}-{\mathrm{Thr}}_M^{\mathrm{Loss}}---\left(3\right);$

The 6th step: determine that grand station provides interference protection to become the transmitted power of sub-carrier: according to the systematic cost p after the power control that calculates; if the systematic cost p after the power control 〉=0; show grand station reduce power be the gain that brings of Pico edge customer greater than the grand user's in station loss own, then will Entered for the 7th step after the transmitted power that provides interference protection to become sub-carrier as grand station, otherwise, show that grand station loss of throughput is excessive, need to improve

To guarantee grand station throughput, at this moment get

As providing interference protection to become the transmitted power of sub-carrier and getting back to for the 5th step, wherein dBm is the power unit milliwatt;

The 7th step: finish this flow process.

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