Dynamic allocation of frequencies associated with local licenses

Abstract

Dynamic allocation of frequencies associated with local licenses: A method, taking into account the deployment of radio base stations, to allocate or reallocate frequencies associated with local licenses. This method relies on estimating interference between two deployments associated with two local licenses. Figure for the abstract: [Fig. 7]

Description

Title of the invention: Dynamic allocation of frequencies associated with local licenses Description of figures

[0001] [Fig.l] shows an example of a local license on a shared frequency band in accordance with the state of the art.

[0002] [Fig.2] describes the procedure for allocating frequencies associated with local licenses in accordance with the state of the art.

[0003] [Fig.3] shows an example of deployment of radio base stations by an operator with local licenses.

[0004] [Fig.4] shows an example of deployment of radio base stations by a second operator with local licenses.

[0005] [Fig.5] shows an example of deployment of radio base stations by a third operator with local licenses.

[0006] [Fig.6] shows an example of frequency preferences associated with local licenses.

[0007] [Fig.7] shows the procedure for allocating frequencies associated with local licenses in accordance with the present invention.

[0008] [Fig.8] shows an alternative procedure for allocating frequencies associated with local licenses in accordance with the present invention.

[0009] [Fig.9] describes the procedure for calculating the interference cost of a so-called “impacting” local license on a so-called “impacted” local license.

[0010] [Fig. 10] shows an example of calculating the interference cost of the deployment associated with a local license on the deployment associated with another local license.

[0011] [Fig. 11] shows a second example of calculating the interference cost of the deployment associated with a local license on the deployment associated with another local license.

[0012] [Fig. 12] shows a third example of calculating the interference cost of one licensed area on another licensed area.

[0013] [Fig. 13] illustrates the calculation of the total interference cost applied to allocation map 1 of [Table 2].

[0014] [Fig. 14] illustrates the calculation of the total interference cost applied to allocation map 2 of [Table 2].

[0015] State of the art on dynamic spectrum sharing

[0016] [Fig.l] shows an example of a local license on a shared frequency band in accordance with the state of the art.

[0017] A local license is associated with a frequency range and an administrative area. This frequency range is not necessarily the same throughout the lifetime of a local license. The procedure for selecting the frequency range associated with a local license is described in [Fig.2].

[0018] In the case of CBRS (“Citizens Broadband Radio Service”), a local license (called “PAL”, or “Priority Access License”), is associated with a county, and the frequency interval of each license is 10 MHz.

[0019] CBRS is a service defined by the FCC regulatory authority ("Federal Communications Commission", document 15-47) allowing the sharing of frequencies on the 3.5 GHz frequency band between three priority levels, or 3 tiers:

[0020] Primary users (or priority users),

[0021] Secondary users PAL (“Priority Access Licensees”),

[0022] Users of the third party GAA (“General Authorized Access”).

[0023] The Wireless Innovation Forum defines the architecture and protocols of the CBRS service, in accordance with FCC requirements.

[0024] The holder of a local license (the “Priority Access Licensee” in the case of CBRS) is entitled to deploy radio base stations in the county associated with that license.

[0025] Once these radio base stations are deployed, the licensee is authorized to create a protection zone around these radio base stations.

[0026] In the case of CBRS, the outline of this protection zone (called “PPA” or “PAL Protection Area”) is calculated by the SAS server (or “Spectrum Access System”, or spectrum access controller) to which the radio base stations are connected) as a function of the radio coverage of each deployed radio base station, up to a reception threshold of -96 dBm / 10 MHz.

[0027] Several separate protection zones can be created in the same county.

[0028] Furthermore, the outline of a protection zone may extend over several counties.

[0029] The method for creating a PPA is described in requirement R2-PAL-02 of document WINNF-TS-0112.

[0030] At each point in a protection zone, the licensee, i.e. the operator to whom one or more local licenses are allocated, is protected from interference generated by radio base stations deployed nearby by other licensees, up to a predefined protection threshold.

[0031] In the case of CBRS, this protection threshold is -80 dBm / 10 MHz.

[0032] State of the art on the allocation of frequencies associated with local licenses

[0033] [Fig.2] describes the procedure for allocating frequencies associated with licenses local in accordance with the state of the art.

[0034] This procedure is executed, for example by the SAS server, following the acquisition of local licenses (for example following an auction of local licenses), and aims to select the frequencies that best satisfy the preferences provided by each license holder.

[0035] In step 1, each licensee provides, for each county for which it holds one or more licenses, its frequency preferences.

[0036] These preferences may, for example, consist of indicating, for each 10 MHz channel, one of the following 3 alternatives:

[0037] - This channel is preferred by the licensee,

[0038] - This channel is acceptable to the licensee,

[0039] - This channel should be avoided.

[0040] Furthermore, in the event that the licensee holds licenses in contiguous counties, the licensee may indicate whether he wishes the frequencies obtained at the end of this allocation procedure to be identical in these counties.

[0041] For a given county, several licensees may hold local licenses.

[0042] In the case of CB RS, each county is associated with a maximum of 7 local licenses.

[0043] A licensee may not hold more than 4 licenses for a given county.

[0044] Step 2 of [Fig.2] consists of filtering, for each county, the possible frequency allocations, and retaining those which best satisfy the preferences of each license holder in that county.

[0045] This step may consist of giving a score to each possible frequency allocation in a given county, then selecting the allocations whose score exceeds a predefined threshold, or even selecting the N allocations whose score is the highest, N being predefined.

[0046] The higher the number of allocations selected, the more complex step 3 will be.

[0047] This score can be calculated as follows:

[0048] For each local license in the county, the score is incremented by the value "-1" in the case where the licensee's preference for the frequency assigned to this local license is "to be avoided", by the value "0" in the case where this preference is "acceptable", and by the value "1" in the case where this preference is "preferred".

[0049] For the sake of fairness, some frequency allocations may be excluded, even if the score obtained is high, for example in the case where one of the county's licensees does not obtain any desired frequency.

[0050] [Tables 1] County C1 (PAL_C1_0pA on F1, | PAL C1 OpB on F2) (PAL_C1_OpB on Fl, PALmC1_OpA on F2) j County C2 (PAL_C2_OpA on F1, PAL_C2_OpB on F2) | (PAL_C2_OpB on Fl, PAL_C2_OpA on F2) County C3 (PAL_C3_OpC on Fl ) County C4 (PAL_C4_OpC on F1) (PAL_C4_OpC on F2)

[0051] An example of frequency allocations retained at the end of this step 2 is detailed in [Table 1] above.

[0052] When an operator has local licenses in neighboring counties, it can indicate whether it wishes the frequencies allocated to these local licenses following the procedure described in [Fig.2] to be the same.

[0053] Step 3 of [Fig.2] consists of identifying, among all the frequency allocations obtained at the end of step 2, the “allocation maps” which best satisfy the geographical contiguity preferences provided by the licensees.

[0054] In a large territory, for example the United States, this step can be carried out in geographical areas smaller than the entire territory. A geographical area can for example be a “CMA” or “cellular market area” as defined by the FCC in the United States.

[0055] An “allocation map” for a given geographical area is the list of frequency allocations of all local licenses belonging to this geographical area.

[0056] An example of possible “allocation maps” retained at the end of this step 3 is detailed in [Table 2].

[0057] Deployment example

[0058] [Fig.3] shows an example of deployment of radio base stations by an operator with local licenses.

[0059] In the remainder of the invention, the county is taken as an example of an administrative area associated with a local license.

[0060] In this example, operator A holds a license, with identifier “PAL_Cl_OpA”, associated with county Cl, and a license with identifier “PAL_C2_OpA” associated with county C2.

[0061] In the area associated with the local license “PAL_Cl_OpA”, operator A has created a protection zone Zl_Cl_OpA, in which two radio base stations are deployed.

[0062] In the area associated with the local license “PAL_C2_OpA”, operator A has created a protection zone Z2_C2_OpA, in which a radio base station is deployed.

[0063] [Fig.4] shows a second example of deployment of radio base stations by an operator with local licenses.

[0064] In this example, operator B holds a license with identifier “PAL_Cl_OpB” associated with county Cl, and a license with identifier “PAL_C2_OpB” associated with county C2.

[0065] [Fig.5] shows a third example of deployment of radio base stations by an operator with local licenses.

[0066] In this example, operator C holds a license with identifier “PAL_C4_OpC” associated with county C4, and a license with identifier “PAL_C3_OpC” associated with county C3.

[0067] [Fig.6] shows an example of frequency preferences associated with the local licenses of operators A, B and C described in [Fig.3], [Fig.4], and [Fig.5].

[0068] These frequency preferences are used during the frequency allocation procedure, as described in [Fig.2].

[0069] It is assumed that 4 frequencies are available, from Fl to F4.

[0070] The county table Cl shows for example that operator A, who has a local license in this county, indicated that Fl and F2 are its preferred frequencies, that F3 is an acceptable frequency, and that F4 is a frequency to be avoided.

[0071] [Table 1] shows, for each county, the list of frequency allocations obtained at the end of step 2 of [Fig.2], taking as input parameters the frequency preferences described in [Fig.6].

[0072] For example, for county Cl, the two allocations obtaining the best score according to the calculation described in [Fig.2] are the following:

[0073] 1) Either the frequency Fl is allocated to the local license PAL_Cl_OpA and the frequency F2 is assigned to the local license PAL_Cl_OpB.

[0074] 2) Either the frequency F2 is allocated to the local license PAL_Cl_OpA and the frequency Flest assigned to the local license PAL_Cl_OpB.

[0075] Similarly, for county C2, the two allocations obtaining the best score according to the calculation described in [Fig.2] are the following:

[0076] 1) Either the frequency Fl is allocated to the local license PAL_C2_OpA and the frequency F2 is assigned to the local license PAL_C2_OpB.

[0077] 2) Either the frequency F2 is allocated to the local license PAL_C2_OpA and the frequency Fl is assigned to the local license PAL_C2_OpB.

[0078] [Tables2] Allocation Card 1 County Cl: (PAL_C1_OpAsur FL PAL_C1_OpB F2) County C2: (PAL_C2_OpA on Fl, PAL_C2_OpB on F2) i County C3: (PAL_C3_OpC on Fl) i County C4: (PAL_C4_OpC on Fl) Allocation Card 2 County Cl: (PAL_C1_OpA on F2, PAL_C1_Op3 Fl} | County C2: (PAL_C2_OpA on F2, PAL_C2_OpB on F1 ) County C3: (PAL_C3_OpC on Fl ) County C4: (PAL_C4_QpC on F1)

[0079] [Table 2] above shows the list of “allocation maps” obtained at the end of the execution of step 3 of [Fig.2], that is to say the list of “allocation maps” best satisfying the criterion of geographical contiguity, among all the “allocation maps” obtained at the end of step 2 of [Fig.2].

[0080] In this example, it is assumed that operators A, B, C all three wish that the geographical contiguity criterion be satisfied for their respective local licenses.

[0081] In this example, two allocation maps best satisfy the geographic contiguity criterion.

[0082] These two "allocation maps" are equivalent from the point of view of the frequency preferences illustrated in [Fig.6]. Therefore, the SAS server can arbitrarily choose to allocate frequencies to local licenses in accordance with allocation map 1 or allocation map 2 described in [Table 2].

[0083] Conversely, for example, an allocation map which would assign the frequency F2 to the license “PAL_C4_OpC” could not satisfy the criterion of geographical contiguity for operator C since the only allocation retained at the end of step 2 of [Fig.2] for the local license “PAL_C3_OpC” in the neighboring county C3, is the frequency Fl, as illustrated in [Table 1].

[0084] Description of the problem

[0085] The frequency allocation procedure described in [Fig.2] does not take into account the deployment of licensees' radio base stations.

[0086] Depending on the deployment of the licensees' radio base stations, the frequency allocations obtained following the procedure described in [Fig.2] may prove unsatisfactory, or even unusable, for the licensees.

[0087] In particular, in the case where two operators, each holding a local license in neighboring counties, create protection zones near the border between these two counties, the authorized transmission power of the radio base stations in each protection zone may be reduced by the SAS server, in order to guarantee that at any point in each protection zone, the authorized interference threshold, guaranteed for each local license, is not exceeded.

[0088] Furthermore, the deployment of radio base stations on a given local license is likely to change over the lifetime of a local license.

[0089] It follows that an allocation of frequencies which is initially satisfactory for operators is likely to deteriorate over time.

[0090] The present invention addresses this limitation by introducing a procedure for allocating or re-allocating frequencies associated with local licenses taking into account the deployment of licensees. This procedure is based on a method for estimating interference between two deployments associated with two local licenses, as described in more detail in the remainder of the invention. Statement of the invention

[0091] The method according to the invention, taking into account the deployment of radio base stations, for allocating or reallocating the frequencies associated with local licenses, each local license authorizing the licensee to create protection zones around the deployed radio base stations, characterized by the following operations and considering that each local license is associated with an administrative zone, that these operations are carried out by a spectrum access controller on a given geographical area, and that a geographical area is made up of a contiguous set of administrative zones: i. Indication, by the holder of one or more local licenses, to the spectrum access controller: a. frequency preferences for these local licenses, b. geographical contiguity preferences, indicating local licenses from neighboring administrative areas associated with the same licensee for which the frequency allocated following this procedure should preferably be the same. ii. for each administrative area, identification of the frequency allocations that best meet the frequency preferences of the local licenses associated with that administrative area. iii. identification of allocation maps that best satisfy the geographic contiguity preferences provided by the licensees in step i, an allocation map, over a given geographic area, being made up of the list of frequencies allocated to each of the local licenses belonging to this geographic area. iv. For each pair of two local licenses associated with neighboring administrative areas and held by different licensees, estimate of the interference cost caused by the deployment of radio base stations of the first local license, called the impacting license, on the deployment of the second local license, called the impacted license, and vice versa. v. selection of the allocation map for which the total interference cost is the lowest, this total interference cost being made up, for a given allocation map, of the sum of the interference costs calculated in step iv and applicable for this allocation map, an interference cost being said to be applicable if the impacting license and the impacted license are on the same frequency.

[0092] The method according to the invention, characterized in that the estimation of said interference cost of an impacting local license on an impacted local license consists of summing the interference cost of each radio base station of the deployment associated with the impacting license on the impacted local license.

[0093] The method according to the invention, characterized in that said interference cost of a radio base station (BS), is the sum of the interference value (I(BS, P)) caused by this base station at each point (P) of each protection zone associated with the impacted license.

[0094] The method according to the invention, characterized in that said interference value (I(BS, P)) takes the value 0 in the case where the interference estimated at point P is lower than a predefined threshold, and the value 1 in the opposite case.

[0095] The method according to the invention, characterized in that said interference value (I(BS, P)) takes the value 0 in the case where the interference estimated at point P is lower than a predefined threshold, and the value of the difference between the estimated interference and this predefined threshold in the opposite case.

[0096] Description of the invention

[0097] [Fig.7] shows the procedure for allocating frequencies associated with local licenses in accordance with the present invention.

[0098] Step 2 of [Fig.7] is identical to step 2 of the state of the art described in [Fig.2], and consists of filtering the frequency allocations according to the frequency preferences.

[0099] Step 3 of [Fig.7] is similar to step 3 of [Fig.2] and consists of filtering the allocation maps according to the geographic contiguity preferences, over a given geographic area.

[0100] In step 4 of [Fig.7], the SAS server estimates the interference cost between deployments of neighboring counties, except in the case where the holder of the local licenses associated with each of these deployments is the same.

[0101] In the deployment example described in figures [Fig.3], [Fig.4] and [Fig.5], this step 4 consists of calculating:

[0102] - The interference cost of radio base stations located in the Zl_Cl_OpA area (associated with the local license PAL_Cl_OpA) on the zone Z2_C2_OpB (associated with the local license PAL_C2_OpB).

[0103] - The interference cost of radio base stations located in the Zl_Cl_OpB area on the Z2_C2_OpA zone.

[0104] - The interference cost of radio base stations located in the Z2_C2_OpB area on the Zl_C4_OpC area.

[0105] - The interference cost of radio base stations located in the Z2_C2_OpB area on the Z2_C3_OpC and Z3_C3_OpC zones.

[0106] - The interference cost of radio base stations located in the Zl_C4_OpC area on the Z2_C2_OpB area.

[0107] - The interference cost of radio base stations located in the areas Z2_C3_OpC and Z3_C3_OpC on the Z2_C2_OpB zone.

[0108] The interference cost is a unitless value, obtained from the estimation of the radio interference caused by each radio base station of a so-called "impacting" local license on a so-called "impacted" local license.

[0109] The calculation of this interference cost is described in more detail in the remainder of the invention.

[0110] [Tables3] PAL_C2_OpA PAL_C4_OpC ^120 PALmC4_OpC PAL_C2mOpA 50 PAL„Q2_OpB PAL_C4_OpC 0 PAL_C4_OpC PAL_C2_OpB 0 PAL_C2_OpA PAL_C3_OpC 0 PAL„C3_OpC PAL_C2_OpA 10 PAL_C2_OpB PAL_C3_OpC 150 PAL_C3_QpC PAL_C2_OpB 200

[0111] [Table 3] above shows the interference cost obtained after performing step 4 of [Fig.2] on the deployment described in [Fig.3], [Fig.4] and [Fig.5].

[0112] For example, the interference cost of the deployment associated with the PAL_C2_OpA license on the protection zones associated with the local PAL_C4_OpC license is 120.

[0113] Selecting the allocation map with the lowest total interference cost

[0114] In step 5 of [Fig.7], the SAS server selects the allocation map having the lowest total interference cost among all possible allocation maps identified in step 3.

[0115] The total total interference cost is the sum of all interference costs associated with a given allocation map.

[0116] For example, we assume that the allocation maps identified at the end of step 3 of [Fig.7] are the two allocation maps described in [Table 2]

[0117] [Fig. 13] illustrates the calculation of the total interference cost applied to allocation map 1 of [Table 2].

[0118] In this allocation map, the only local licenses that impact deployments of different operators in neighboring counties are:

[0119] - the license of operator C on account C4 (PAL_C4_OpC)

[0120] - the license of operator C on account C3 (PAL_C3_OpC)

[0121] - the license of operator A on account C2 (PAL_C2_OpA)

[0122] The interference cost between each neighboring local license is indicated on the arrows and corresponds to the interference cost values ​​described in [Table 3].

[0123] The total interference cost for allocation 1 is therefore 120 + 50 + 0 + 10 = 180.

[0124] [Fig. 14] illustrates the calculation of the total interference cost applied to the card allocation 2 of [Table 2].

[0125] In this allocation map, the only local licenses that impact deployments of different operators in neighboring counties are:

[0126] - the license of operator C on account C4 (PAL_C4_OpC)

[0127] - the license of operator C on account C3 (PAL_C3_OpC)

[0128] - the license of operator B on account C2 (PAL_C2_OpB)

[0129] The total interference cost for allocation map 2 is therefore 150 + 200 + 0 + 0 = 350.

[0130] At the end of step 5, the allocation map selected in this example is therefore allocation map 1, whose total interference cost is 180.

[0131] Calculation of interference cost according to the present invention

[0132] [Fig.9] describes the procedure for calculating the interference cost of a so-called “impacting” local license on a so-called “impacted” local license.

[0133] In step 1, the interference cost is initialized to the value zero.

[0134] In step 2, the SAS server adds the interference cost of each station radio base associated with the local license impacting the impacted local license.

[0135] The calculation of the interference cost of a radio base station carried out in step 2 consists of summing the interference value (I(BS, P)) caused by this base station at each point (P) of each protection zone associated with the impacted license (for example by taking a point every 80 meters inside each protection zone).

[0136] [Fig. 10] shows an example of calculating the interference cost of the deployment associated with a local license on the deployment associated with another local license.

[0137] In this example, it is assumed that operator A has a local license associated with county 1 (PAL_Cl_OpA).

[0138] This local license authorizes operator A to deploy radio base stations in county A, as well as to create protection zones associated with these radio base stations.

[0139] In this example, operator A has created two protection zones ZI and Z2 associated respectively with radio base stations BS1 and BS2.

[0140] Assume that Operator B has a local license associated with County 2 (PAL_C2_OpB).

[0141] In this example, operator B has created a protection zone Z3 associated with radio base stations C3 and C4.

[0142] In accordance with the procedure described in [Fig.9], the calculation of the interference cost of the deployment associated with the local license PAL_Cl_OpA on the deployment associated with the local license PAL_C2_OpB consists of:

[0143] 1) identify the radio base stations of the impacting deployment. In this example, it There are two radio base stations (BS1 and BS2).

[0144] 2) identify the protection zones of the impacted deployment. In this example, there are a protection zone (Z3).

[0145] 3) for each radio base station BS identified in 1), and for each point P of the protection zone Z3, evaluate the interference value I(BS, P).

[0146] In this example, it is assumed that the interference value I(BS, P) returns the value 0 in the case where the estimated interference of the radio base station BS at point P is lower than a predefined threshold, and the value 1 otherwise.

[0147] The calculation of the interference can be carried out using a radio propagation algorithm, taking into account the parameters of the radio base station having an impact on the radio propagation such as:

[0148] -latitude,

[0149] - longitude,

[0150] - the height,

[0151] - the parameters of the antenna associated with the radio base station (for example azimuth and beam width),

[0152] - the radiation pattern,

[0153] - the authorized transmission power.

[0154] The right part of [Fig. 10] shows, for each impacting radio base station, the points in the protection zone Z3 where the interference is higher than the predefined threshold. Each of these points is illustrated by a gray square.

[0155] In this example, the function I(BS, P) returned the value 1 at 5 points for the radio base station BS1 and at 4 points for the radio base station BS2.

[0156] The interference cost of the deployment associated with the local license PAL_Cl_OpA on the deployment associated with the local license PAL_C2_OpB is therefore 5 + 4 = 9.

[0157] [Fig. 11] shows a second example of calculating the interference cost of the deployment associated with a local license on the deployment associated with another local license.

[0158] In this example, operator B has created a protection zone Z3 associated with the radio base station BS3 and a protection zone Z4 associated with the radio base station BS4.

[0159] In accordance with the procedure described in [Fig.9], the calculation of the interference cost of the deployment associated with the local license PAL_Cl_OpA on the deployment associated with the local license PAL_C2_OpB consists of:

[0160] 1) identify the radio base stations of the impacting deployment. In this example, it There are two radio base stations (BS1 and BS2).

[0161] 2) identify the protection zones of the impacted deployment. In this example, there are two protection zones (Z3 and Z4).

[0162] 3) for each radio base station BS identified in 1), and for each point P of the protection zone Z3, evaluate the interference value I(BS, P).

[0163] The right part of [Fig. 11] shows, for each impacting radio base station, the points in the protection zones Z3 and Z4 where the interference is greater than the predefined threshold.

[0164] In this example, the function I(BS, P) returned the value 1 at no point for the radio base station BS1 and at 1 point for the radio base station BS2.

[0165] The interference cost of the deployment associated with the local license PAL_Cl_OpA on the deployment associated with the local license PAL_C2_OpB is therefore 1.

[0166] Alternative calculation of interference cost

[0167] In an alternative, the function I(BS, P) returns the value 0 in the case where the estimated interference of the radio base station BS at point P is lower than a predefined interference threshold, and the difference between the estimated interference and this predefined threshold in the opposite case.

[0168] [Fig. 12] shows an example of the calculation of the interference cost according to this alternative. The white colored squares indicate the points for which the function I(BS, P) returned the value 0. The gray shaded squares indicate the points for which the function I(BS, P) returned the difference between the estimated interference and a predefined interference threshold.

[0169] The gray gradation illustrates the value of the local interference obtained at each point, increasing from lightest to darkest.

[0170] Alternative to the frequency allocation procedure described in [Fig.7]

[0171] [Fig.8] shows an alternative procedure for allocating frequencies associated with local licenses in accordance with the present invention.

[0172] In this alternative, the selection of allocations according to the interference cost (in step 4) is carried out before the selection according to the geographic contiguity criterion (in step 5).

[0173] Step 4 may consist, for example, of selecting the allocation cards having a total interference cost lower than a predefined threshold, or of selecting the N allocation cards whose total interference cost is the lowest, N being predefined.

Claims

1. Claims A method, taking into account the deployment of radio base stations, for allocating or reallocating frequencies associated with local licenses, each local license authorizing the licensee to create protection zones around the deployed radio base stations, characterized by the following operations and considering that each local license is associated with an administrative zone, that these operations are carried out by a spectrum access controller over a given geographical area, and that a geographical area is made up of a contiguous set of administrative zones: i. Indication, by the holder of one or more local licenses, to the spectrum access controller: a. frequency preferences for these local licenses, b. geographical contiguity preferences, indicating local licenses from neighboring administrative areas associated with the same licensee for which the frequency allocated following this procedure should preferably be the same. ii. for each administrative area, identification of the frequency allocations that best meet the frequency preferences of the local licenses associated with that administrative area, this step being able, for example, to consist of giving a score to each possible frequency allocation, then selecting the allocations whose score exceeds a predefined threshold, or even selecting the N allocations whose score is the highest, N being predefined. iii. identification of the allocation maps which best satisfy the geographical contiguity preferences provided by the licensees in step i, this identification being able, for example, to consist of selecting the allocation maps for which the geographical contiguity criterion is satisfied for the greatest number of local licenses, an allocation map, over a given geographical area, being consisting of the list of frequencies allocated to each of the local licenses belonging to this geographical area. iv. For each pair of two local licenses associated with neighboring administrative areas and held by different licensees, estimate of the interference cost caused by the deployment of radio base stations of the first local license, called the impacting license, on the deployment of the second local license, called the impacted license, and vice versa. v. selection of the allocation map for which the total interference cost is the lowest, this total interference cost being made up, for a given allocation map, of the sum of the interference costs calculated in step iv and applicable for this allocation map, an interference cost being said to be applicable if the impacting license and the impacted license are on the same frequency.

2. Method according to claim 1, characterized in that the estimation of said interference cost of an impacting local license on an impacted local license consists of summing the interference cost of each radio base station of the deployment associated with the impacting license on the impacted local license.

3. Method according to claim 2, characterized in that said interference cost of a radio base station (BS) is the sum of the interference value (I(BS, P)) caused by this base station at each point (P) of each protection zone associated with the impacted license.

4. Method according to claim 3, characterized in that said interference value (I(BS, P)) takes the value 0 in the case where the interference estimated at point P is lower than a predefined threshold, and the value 1 in the opposite case.

5. Method according to claim 3, characterized in that said interference value (I(BS, P)) takes the value 0 in the case where the interference estimated at point P is lower than a predefined threshold, and the value of the difference between the estimated interference and this predefined threshold in the opposite case.

6. Method according to claims 1 to 5, characterized in that steps iv and v of claim 1 are carried out before step iii.

Images