FR3090261A1 - COMMUNICATION METHOD IN A CELLULAR NETWORK IMPLEMENTING PEER-TO-PEER COMMUNICATIONS - Google Patents

Abstract

The present invention relates to a method of communication in a cellular network implementing peer-to-peer communications. Said method comprises the following steps: at least one device of said network, called first device (D1), connected to a base station (BS) of said network, associates in peer-to-peer and establishes a communication in half-duplex with another device on the network, called the second device (D2); said first device (D1) measures the power received from said second device (D2) and the ID power received from other devices on the network transmitting at the same time as the second device (D2); the first device (D1) transmits to a controller the results of these measurements, as well as its own transmission power P1 and its own self-interference factor b; on the basis of at least this information, the controller checks a certain condition; if this condition is satisfied, the controller triggers the procedures necessary to establish simultaneous data transmissions from the second device (D2) to the first device (D1) and from the first device (D1) to said base station (BS) of the network, and in reverse, in which the first device (D1) operates in full-duplex. Figure for the abstract: Fig. 1

Description

Description

Title of the invention: COMMUNICATION METHOD IN A CELLULAR NETWORK IMPLEMENTING PEER-TO-PEER COMMUNICATIONS

The present invention relates to communications in a cellular radio network, as well as to communications between several client devices (“User Equipment”, or EU, in English), such as computers, mobile phones, or tablets. digital, which will generally be referred to as "devices" below.

The invention relates more particularly to peer-to-peer communications (or P2P for "Peer-to-Peer" in English) between several devices. By peer-to-peer communication between two devices is meant the exchange of data between these two devices without typically passing through a central server. No limitation is attached to the type of data exchanged between devices (voice, text, etc.) during a peer-to-peer communication. This communication can consist of a direct exchange of data between the two devices (this is called D2D or "Device-to-Device" communication in English), or an exchange via one or more intermediate devices implementing two by two D2D communications, these intermediate devices forming a route between the two devices seeking to communicate with each other. All of the devices thus connected peer-to-peer form a mesh network or "mesh" network without a central hierarchy, also called an ad hoc network. When devices on the ad hoc network are mobile, we speak of a MANET network (for Mobile Adhoc NET work in English).

The devices within the same ad hoc network can use different connectivity technologies to detect the presence of neighboring devices, identify the applications or services made available by these neighboring devices, and connect to each other in order to communicate peer-to-peer. They can notably rely on Bluetooth, WiEi (Wireless Eidelity), WiEi Direct, or LTE (Long Term Evolution) Direct technologies. They can also be connected to elements external to the ad hoc network, such as for example to other devices belonging to operator networks (eg 3G, 4G, 5G networks, etc.) or to private networks, to access, for example, the public Internet network.

Mesh networks are arousing great interest today. They have, for example, demonstrated their effectiveness in providing resilient communication services in the event of voluntary or unintentional disruption of traditional communication networks, for example in wartime or following a natural disaster. Such mesh networks can also be envisaged in order to protect against cyber surveillance or to prevent data exchanged between two devices from passing over the public Internet network. Many other applications of mesh networks can also be envisaged.

Consider now, with reference to Figure 1, a cellular network consisting of base stations BS (for "Base Station" in English) and devices connected together in D2D.

Consider two such devices DI and D2. To receive or transmit data to the network, one of the two devices must transmit or receive data to the BS which covers the area in which it is located. Consider the situation in which the device D2 must pass through the device DI to send data to the BS: D2 transmits to Dl, then DI retransmits to the BS the data received from D2.

In the state of the art, the transmission of D2 to Dl and the transmission of Dl to the BS cannot be done simultaneously on a given bandwidth. In fact, the device D1 cannot receive data from D2 and retransmit them simultaneously to the BS on the same frequency. Consequently, according to the state of the art, these two functions, namely receiving data from D2 on the one hand (transmission T ₂ in FIG. 1), and transmitting this data to the BS on the other part (transmission Ti in Figure 1) are implemented at separate times.

Consequently, the performance and the quality of service offered by the network are lower than if these two transmissions could be carried out simultaneously.

The present invention therefore relates to a method of communication in a cellular network implementing peer-to-peer communications. Said method comprises the following steps:

- at least one device of said network, said first device, connected to a base station of said network, associates in peer-to-peer and establishes a communication in half-duplex with another device of the network, says second device,

said first device measures the power received from said second device and the power ID received from other devices on the network transmitting at the same time as the second device,

- the first device transmits to a controller the results of these measurements, as well as its own transmitting power PI and its own self-interference factor b,

- at least on the basis of this information, the controller determines the signal to noise ratio plus SINR _Hj2 i interference concerning the signal received by the first device from the second device, as well as the signal to noise ratio plus SINRh.io interference concerning the signal received by said base station from the first device, and calculates the quantity C such that

1 1

--------------- = ---------—-------- -I ----------— - - ---—

C log (1 + SINR) log (1+ SiNR)

- the controller checks:

* in the case where the estimated speed of the link between the first device and the second full-duplex device is lower than the estimated speed of the full-duplex link between the first device and the base station, the condition

SINRp.21> exp (C) - 1, where SINR _Fj2 i is an estimate of the signal-to-noise ratio plus interference concerning the signal that would be received by said first device from the second device if the communication was carried out in full-duplex , or * in the case where the estimated speed of the link between the first device and the second device in full-duplex is greater than the estimated speed of the link between the first device and the base station in full-duplex, the condition

SINR _f> io> exp (C) - 1, where SINRp.io is an estimate of the signal to noise ratio plus interference concerning the signal which would be received by the base station from the first device if the communication was carried out in full -duplex, and - if said condition is verified, the controller triggers the procedures necessary to establish simultaneous transmissions of data from the second device to the first device and from the first device to said network base station, and in the opposite direction, in which the first device operates in full-duplex.

Thus, the present invention provides a method for minimizing the transmission time in a cellular network implementing D2D communications. This process advantageously exploits the so-called "full-duplex" technique.

We recall (see Wikipedia) that, in the telecommunications field, we call "simplex" (unidirectional) a channel which carries data in one direction. A communication channel which carries data in both directions (bidirectional) is called "duplex"; depending on whether the transmission and reception of data takes place in both directions simultaneously or not, we speak respectively of "full-duplex" or "half-duplex" channel.

In the context of the present invention, a full-duplex system is considered in which the reception and transmission of data are not only simultaneous, but also use the same carrier frequency. The advantage of such a full-duplex system is that it allows better use of the bandwidth not only in time, but also in frequency; in other words, more bandwidth can be used to transmit more data at better data rates.

On the other hand, a full-duplex transmission has the drawback of causing self-interference due to the superposition of signals on the same channel, which tends to decrease the Signal to Interference plus Noise Ratio ("Signal over Interference plus Noise Ratio"). ", Or SINR, in English).

But thanks to the invention, when said condition is verified, the transmission delay between D2D communication devices and the base station to which they are attached can be divided by an important factor compared to the state of art.

According to particular characteristics, said signal to noise ratio plus SINR _Fj2 i interference is estimated by means of the following expression:

SINR = SINR x ----------------,

F, 21H.21 + SINR

WHERE bP <SINR = ---------.

L. + Nffj where N * is the power of thermal noise.

Thanks to these provisions, the signal-to-noise ratio plus SINR _Fj2 i interference can be estimated from measurements made in half-duplex.

According to other particular characteristics, said signal to noise ratio plus SINR interference _Fj io is estimated by means of the following expression:

SINR = SINR x --------—----——-.

F, 10 H.W.

-i- sinr _mw

Thanks to these provisions, the signal to noise ratio plus SINR interference _Fj i ₀ can be estimated from measurements made in half-duplex.

Correspondingly, the invention relates to a controller capable of operating in a cellular network implementing peer-to-peer communications. Said controller comprises means for:

- receive, from at least one device of said network, said first device, the power received by said first device from another device of the network, said second device, and the power I _D received by the first device from other network devices transmitting at the same time as said second device, as well as the transmission power Pi and the self-interference factor b of the first device, - at least on the basis of this information, determine the signal-to-noise ratio plus interference SINR _H , 2i concerning the signal received by the first device from the second device, as well as the signal-to-noise ratio plus interference SINR _h , io concerning the signal received from the first device by a base station to which the first device is connected, and calculates the quantity C such that

1 1

-------------- = ----------------------- + ----------- ----------- C iog (1 + SiNR.) Log (H SINR.)

- check:

* in the case where the estimated speed of the link between the first device and the second device in full-duplex is lower than the estimated speed of the link in full-duplex between the first device and said base station, the condition

SINRp.21> exp (C) - 1, where SINR _Fj 2i is an estimate of the signal-to-noise ratio plus interference concerning the signal that would be received by said first device from the second device if the communication was carried out in full-duplex , or * in the case where the estimated speed of the link between the first device and the second device in full-duplex is greater than the estimated speed of the link between the first device and the base station in full-duplex, the condition

SINR _Fj io> exp (C) - 1, where SINRp.io is an estimate of the signal-to-noise ratio plus interference concerning the signal which would be received by the base station from the first device if the communication was carried out in full- duplex, and - if the condition is satisfied, trigger the procedures necessary to establish simultaneous data transmissions from the second device to the first device, and from the first device to said network base station, in which the first device operates in full- duplex.

It should be noted that said controller can be hosted, for example, in a base station, or in a centralized entity of the cellular network.

According to particular characteristics, said controller also comprises means for estimating said signal to noise ratio plus SINR _Fj2 i interference by means of the following expression:

SÎNR = SINR x --------------------------.

F.21 + SiNR seif. ·] Where bP, SINR = ---------- · ——.

self, 'where N * is the power of thermal noise.

According to other particular characteristics, said controller also comprises means for estimating said signal to noise ratio plus interference SINR _Fj i ₀ by means of the following expression:

SINR = SINR x ----------------------------.

F.10 HW + SINR

H.2C

The advantages offered by these controllers are essentially the same as those offered by the correlative processes succinctly described above.

Note that it is possible to make these controllers in the context of software instructions and / or in the context of electronic circuits.

The invention also relates to a computer program downloadable from a communication network and / or stored on a medium readable by computer and / or executable by a microprocessor. This computer program is remarkable in that it includes instructions for the execution of the steps of the communication method succinctly described above, when it is executed on a computer.

The advantages offered by this computer program are essentially the same as those offered by said method.

Other aspects and advantages of the invention will appear on reading the detailed description below of particular embodiments, given by way of nonlimiting examples. The description refers to:

[Fig. 1] Figure 1, mentioned above, which shows an embodiment of the invention.

In this embodiment, we consider a cellular network comprising: - at least one base station,

- at least one D2D communication device, which is not directly connected to a base station, and

- at least one D2D communication device, which is also connected to a base station.

The cellular network can also include at least one device directly connected to a base station, and which is not in D2D communication.

The cellular network further comprises a controller, the role of which will be described below. As indicated above, this controller can for example be hosted in a base station, or in a centralized entity of the cellular network.

As an example, we now consider a data transmission from a device D ₂ to a device D _B and a retransmission of this data by Di to the base station BS to which Di is connected. The DI device has a transmitter / receiver capable of operating in full-duplex.

We first examine the case where the device D ₂ transmits to the device D _b and the device Di transmits to the BS in half-duplex (ie, Di and D ₂ do not transmit simultaneously).

Called SINR _r , ₂ i the signal to noise ratio plus interference concerning the signal received by Di from D ₂ . It is worth:

[0035]

P ₂ 1

SÏNR = - -----— ta + Ng,

Where P ₂ i is the power received by Di from D ₂ , I _D is the interfering power from other devices on the network transmitting at the same time as D ₂ , and N * is the power of thermal noise.

We call SINR _h , io the signal to noise ratio plus interference concerning the signal received by BS from Dp II is worth:

[0038]

S1NR = —-----,

H, 18

[:; + Ni ·, where Pio is the power received by the base station SB from the device Dp. The signal-to-noise ratio plus interference concerning the signal received by BS from D ₂ is called SINR _{H 20} . It is worth:

R _2fi

SïNR = ------------------.

H, 23 ta + N _(h

Where P ₂₀ is the power received by the base station SB from the device D ₂ .

Now consider the case where the device D ₂ transmits to the device Di in fullduplex (ie the device Dl simultaneously transmits to the BS).

We call SINRpio the signal-to-noise ratio plus interference concerning the signal received by BS from Dp II is worth:

P _w

SÏNR =.

F, W

Father * ta +

Therefore:

[0046]

SÏNR = SÏNR X.

F.tÔH13 + S! NR

H .. 20

The value of SINRpio can thus be estimated from measurements made in half-duplex.

SINR _Fj2 i is called the signal-to-noise ratio plus interference concerning the signal received by Di from D ₂ . As recalled above, the simultaneous transmissions associated with full-duplex operation generate self-interference in DL. It can be shown that SINR _Fj2 i can be estimated from measurements made in half8 duplex, by means of the following expression:

₁

SINR = SINR x --------------------------,

F, 21 + SI N R seif.i

WHERE b PT

IF N R = ——------—.

selM l _D + Njh

Here, Pi is the emission power of the device Dp and b is a self-interference factor (characteristic of the device concerned), as described in the article by T. Huusari et al. entitled "Wideband Self-Adaptive RF Cancellation Circuit for Full-Duplex Radio: Operating Principle and Measurements" (cf. https://arxiv.org/pdf/1503.02877.pdf).

We will now study the data transmission times between D ₂ to the BS via Dp We denote by W the bandwidth available for transmissions from D ₂ to Dp and from Di to the BS.

The duration of transmission of a volume V of data from D ₂ to the BS via Di is:

- half-duplex

[°° 54] VV □ = -------------- + --------.... _e t

HD.

T _{2 (HD} 1 \ hd

- in full-duplex

[0056]

V

D = --------______---------- FD min (T _2FD; 1 \ _FD )

Where

* Ti.hd is the speed of the link (Di to BS) in half-duplex, which is

T _{1> HD} = W log ₂ (l + SINR _h , io),

* T _1FD is the estimated throughput of the link (Di to BS) if it was carried out in fullduplex, which is equal to Ti _FD = W log ₂ (l + SINR _{F> 10} ),

* T _{2 HD} is the speed of the link (D ₂ to DJ in half-duplex, which is

T ₂ , hd = w log ₂ (l + SINRh, ₂ i), and

* T _{2> FD} is the estimated bit rate of the link (D ₂ to DJ if it was performed in full9 duplex, which is T _{2> FD} = W log ₂ (l + SINR _Fj2 i).

Consequently, the duration in full-duplex is less than the duration in half-duplex if:

1 1 mitXTa,, R3, Tj, fd) T2 .. HD Ti _; HD

We must therefore distinguish two cases. The controller (mentioned above) determines in which case we are at a given time, from the measurements which are reported to it.

In the first case:

T _2jF d <Ti _jF d.

In the first case, the above condition becomes:

JΊ

Your. FD Tp Hi s T; _Comics

And therefore:

111

--------------------- <-------------------- + ------- ----------------, log (1+ SINR ₊ } log (1+ SINR) log (1+ SINR

We define a quantity C verifying:

_{1 1i}

------------- = —------------------- + --------------- -------- C log (1+ SINR.) Log (1+ SINR)

A full-duplex transmission therefore makes it possible to minimize the transmission delay compared to a half-duplex transmission if the following condition:

SINR _{f> 21} > exp (C) - 1

Is verified.

In the second case:

T _2jFD > T _1jFD .

In the second case, the above condition becomes:

_{1 1 1}

------------—- <--------—: —— + ——------— _;

T-î.FD T _{2 [} HG T-ÎHO

And therefore:

[0081]

1 1

----------- ——— <------------—------ + --------------- ----— log (1+ SINR) log (1+ SiNR} log (1+ SINR)

F, ’: * 3. H.2't Η.1Ό '

A full-duplex transmission therefore makes it possible to minimize the transmission delay compared to a half-duplex transmission if the following condition:

SINR _f10 > exp (C) - 1

Is verified.

We will now describe the steps of a communication process in a cellular network, according to an embodiment of the invention.

According to a first step, a device Di and a device D ₂ , associate in peer-to-peer, and establish a communication in half-duplex. Regarding this association, we can refer to the articles by William Diego and Jean-Marc Kelif entitled "Improving D2D Communications using 3D Beamforming in 5G Wireless Networks" (cf. https://ieeexplore.ieee.org/stamp/stamp.jsp? tp = & arnumber = 8292625). and "Meeting Energy-Efficient and QoS Requirements of 5G Using D2D Communications" (cf. https://arxiv.org/pdf/1712.06461.pdD.

In a second step, a number of measurements are made.

The device Di measures the power received from the device D ₂ .

The device Di also measures the power received from the other devices of the network transmitting at the same time as D ₂ (these are therefore the interfering powers involved in the calculation of I_D, see above). To do this, Di can for example use the “Physical Sidelink Discovery Channel - PSDCH” channel, as described in standard TS 36.201, version 14.0.0, Release 14, September 2016, of the 3GPP (3rd Generation Partnership Project).

Optionally, other devices on the network perform the same measurements.

According to a third step, the first device (Di) transmits to a controller (mentioned above) the results of these measurements, as well as its transmission power and its self-interference factor b (mentioned above). above). The controller can optionally store this information in a database.

According to a fourth step, on the basis at least of this information, the controller determines the reports SINR _Hj2 i and SINR _Hj io, and calculates the quantity C defined above.

According to a fifth step, at the time of the request for transmission from Di to the SB, or periodically (so as to be able to take into account a possible modification of the transmission conditions), the controller:

- estimates SINR _F , 2i, and checks the condition

SINR _Fj2 i> exp (C) - 1

In the case where T _{2> FD} <T _{t FD} , or

- estimates SINR _F> 10, and checks the condition

SINR | | ₍₎ > cxp (C) - 1

In the case where T _{2 FD} > T _{t FD} .

Finally, according to a sixth step:

- if the condition is verified, the controller triggers the procedures necessary to establish simultaneous transmissions of data from D ₂ to D] and from D] to the SB, and in the opposite direction (ie from the SB to D, and from D, to D ₂ ), in which D] operates in full-duplex;

- if the condition is not verified, the controller maintains, or establishes, successive data transmissions from D ₂ to D] then from D] to the SB, and in the opposite direction (ie from the SB to D ] then from D] to D ₂ ), in which D] operates in half-duplex.

The invention can be implemented within nodes, for example base stations or devices able to operate in D2D, communication networks, by means of software and / or hardware components.

The software components can be integrated into a conventional computer program for managing a network node. This is why, as indicated above, the present invention also relates to a computer system. This computer system conventionally comprises a central processing unit controlling by signals a memory, as well as an input unit and an output unit. In addition, this computer system can be used to execute a computer program comprising instructions for the implementation of any of the communication methods according to the invention.

The invention also relates to a computer program downloadable from a communication network comprising instructions for the execution of the steps of a communication method according to the invention, when it is executed on a computer . This computer program can be stored on computer readable media and can be executed by a microprocessor.

This program can use any programming language, and be in the form of source code, object code, or intermediate code between source code and object code, such as in a partially compiled form, or in n any other desirable form.

The invention also relates to an irremovable information medium, or partially or completely removable, readable by a computer, and comprising instructions of a computer program as mentioned above.

The information medium can be any entity or device capable of storing the program. For example, the support may include a storage means, such as a ROM, for example a CD ROM or a microelectronic circuit ROM, or a magnetic recording means, such as a hard disk, or even a USB key. ("USB flash drive" in English).

On the other hand, the information medium can be a transmissible medium such as an electrical or optical signal, which can be routed via an electrical or optical cable, by radio or by other means. The computer program according to the invention can in particular be downloaded from a network of the Internet type.

Alternatively, the information medium can be an integrated circuit in which the program is incorporated, the circuit being adapted to execute or to be used in the execution of any of the communication methods according to the invention .

Claims (1)

[Claim 1] Claims Communication method in a cellular network implementing peer-to-peer communications, comprising the following steps: - at least one device from said network, called first device (Di), connected to a base station (BS) of said network, associates in peer-to-peer and establishes a half-duplex communication with another device on the network, known as the second device (D ₂ ), - said first device (Di) measures the power received from said second device (D ₂ ) and the power I _D received from other devices on the network transmitting at the same time as the second device (D ₂ ), - the first device (DJ transmits to a controller the results of these measurements, as well as its own transmission power Pi and its own self-interference factor b, - at least on the basis of this information, the controller determines the signal to noise ratio plus SINR _Hj2 i interference concerning the signal received by the first device (DJ from the second device (D ₂ ), as well as the signal to noise plus interference SINR _Hj io concerning the signal received by said base station (BS) from the first device (DJ, and calculates the quantity C such that 1 1 1 ——-------- = -------------------— + --------------- ----- C log (1 + SINR) lôg (Ή SINR) - the controller checks: * in the case where the estimated speed of the link between the first device (DO and the second device (D ₂ ) in full-duplex is lower than the estimated speed of the link in full-duplex between the first device (Di) and the base station (BS), the condition SINR _Fj2 i> exp (C) - 1, where SINR _Fj2 i is an estimate of the signal to noise ratio plus interference concerning the signal which would be received by said first device (Di) of the second device (D ₂ ) if the communication was carried out in full-duplex, or * in the case where the estimated speed of the link between the first device (Di) and the second device (D ₂ ) in full-duplex is higher at the estimated speed of the link between the first device (Di) and the base station (BS) in full-duplex, the condition SINR _Fj io> exp (C) - 1, where SINR _Fj io is an estimate of the signal to noise ratio plus interference concerning the signal which would be received by the base station (BS) on the part of the first device (Di) if the communication was carried out in full-duplex, and - if said condition is verified, the controller triggers the procedures necessary to establish simultaneous data transmissions from the second device ( D ₂ ) to the first device (Di) and from the first device (Di) to said base station (BS) of the network, and in the opposite direction, in which the first device (Di) operates in fullduplex. [Claim 2] Communication method according to claim 1, characterized in that said signal to noise ratio plus interference SINR _Fj2 i is estimated by means of the following expression: SINR = SINR X -------------- ------------. F.21 H.21 1 + SINR selï, '· WHERE b Pi SINR = ------------------. seli / î h ⁺ Hh where N * is the power of thermal noise. [Claim 3] Communication method according to claim 1 or claim 2, characterized in that said signal-to-noise ratio plus interference SINR _Fj io is estimated by means of the following expression: SINR = SINR x —--------- ------------. F.18 -ΗΛΟ 1 -Î- SINR H..2G [Claim 4] Controller capable of operating in a cellular network implementing peer-to-peer communications, comprising means for: - receiving, from at least one device of said network, known as the first device (Di), the power received by said first device (Di) from another device of the network, said second device (D ₂ ), and the power I _D received by the first device (Di) from other devices of the network transmitting at the same time that said second device (D ₂ ), as well as the transmission power Pi and the self-interference factor b of the first device (DJ, - on the basis of at least this information, determine the signal ratio on noise plus interference SINR _Hj2 i concerning the signal received by the first device (DJ from the second device (D ₂ ), as well as the signal to noise ratio plus interference SINR _Hj io concerning the signal received from the first device (DJ by a base station (BS) to which the first device (DJ is connected, and calculates the quantity C such that 1 1 1 —-------- = ------—---------- + -------—------ C iog (1+ S! NR.) Tog (1 + SINR J H 21 H, TO - check: * in the case where the estimated speed of the link between the first device (DO and the second device (D ₂ ) in full-duplex is lower than the estimated speed of the link in full-duplex between the first device (DO and said station) basic (BS), the condition SINR _{f> 21} > exp (C) - 1, where SINR _{F. 2} i is an estimate of the signal to noise ratio plus interference concerning the signal which would be received by said first device (DO from the second device (D ₂ ) if the communication was carried out in full-duplex, or * in the case where the estimated speed of the link between the first device (DO and the second device (DO in full-duplex is greater than the estimated speed of the link between the first device (DO and the base station (BS) in full-duplex, the condition SINR _Fj io> exp (C) - 1, where SINR _Fj io is an estimate of the signal to noise ratio plus interference concerning the signal which would be received by the base station (BS) from the first device (DO if communication was done in full-duplex, and - if said condition is satisfied, trigger the procedures necessary to establish simultaneous data transmissions from the second device (D ₂ ) to the first device (DO and from the first device (Di) to said base station (BS) of the network, and in the opposite direction, in which the first device (DO operates in full-duplex. [Claim 5] Controller according to claim 4, characterized in that it further comprises means for estimating said signal to noise ratio plus SINR _Fj2 i interference by means of the following expression: T S1NR = SINR x -------——— F, 2t H, 2 ' 1 + SINR sdU WHERE b P, SINR = ------------ setf.1 In ⁺ Ne, [Claim 6] where N * is the power of thermal noise. Controller according to claim 4 or claim 5, characterized in that it further comprises means for estimating said signal to noise ratio plus interference SINR _Fj i ₀ by means of the following expression: [Claim 7] Base station of a cellular network, characterized in that it comprises a controller according to any one of claims 4 to c. [Claim 8] U. A non-removable, or partially or completely removable, data storage medium comprising computer program code instructions for carrying out the steps of a communication method according to any one of claims 1 to 3. [Claim 9] Computer program downloadable from a communication network and / or stored on a computer-readable medium and / or executable by a microprocessor, characterized in that it comprises instructions for the execution of the steps of a communication method according to any one of claims 1 to 3, when executed on a computer. 1/1