MXPA06007944A - Watermarks/signatures for wireless communications - Google Patents

Abstract

At least one user data stream is layer 2/3 processed, physical layer processed and radio frequency processed. A watermark/signature is embedded at at least one of layer 2/3, physical layer or radio frequency, producing an embedded wireless communication. The embedded wireless communication is wirelessly transferred. The embedded wireless communication is received and the watermark/signature is extracted from the embedded wireless communication.

Description

WATER MARKS / SIGNATURES FOR WIRELESS COMMUNICATIONS FIELD OF THE INVENTION The present invention relates, in general, to wireless communications. More specifically, the present invention is directed to watermarks / signatures for wireless communications.

ANTECEDEMTES Wireless systems are susceptible in several aspects. These sensitivities are increasing as new wireless technologies grow in frequency. Ad-hoc networks, where individual users communicate with each other directly without using intermediary network nodes create new susceptibilities for users and for networks. These sensitivities can be categorized as issues related to "trust", "rights", "identity", "privacy", and "security". The term "trust" refers to the security of the information communicated in these systems can be shared. To illustrate, a wireless user may want to know that a communication has been sent from a secure source and using secure communication nodes. The user in an ad-hoc network may not be aware that the communication was transferred over a "hack er" wireless device with packet sniffer software. Additionally, with the use of tunnels, the intermediate nodes that transfer the communication can be transparent to the wireless user. The term "rights" ("rights management") refers to data control. To illustrate, a wireless user may have limited rights in a wireless system. However, if that user conspires (knowingly or unknowingly) with a second node that has superior rights, that user can obtain rights beyond those that are allowed to the user. The term "identity" refers to the control linked to the identity of the wireless user. To illustrate, a dishonest wireless device may attempt to access a wireless network pretending to be an authorized user of the network, by utilizing the identity of such authorized user. The term "privacy" refers to maintaining the privacy of the individual, the data and the context. A wireless user may not want others to know what sites on the network (websites) they visit and, in particular, the information sent to such sites, such as financial, medical, etc. The term "security" refers to the security of the information and the context, such as preventing an unauthorized individual from accessing the information of a wireless user.

To reduce the susceptibility of wireless networks, techniques such as wired equivalent privacy (WEP), Wi-Fi Protected Access (WPA), Extensible Authentication Protocol (EAP), IEEE 802. lli and GSM-based encryption are used. Although these techniques provide some protection, they remain susceptible to the trusts, rights, identity, privacy, and security issued. To illustrate, although a particular wireless communication node can present the correct WEP keys to communicate with a wireless user, that user may not know if he can "trust" that node. Additionally, user authentication that uses these keys typically occurs at higher levels of the communication chain. Accordingly, even when such controls are in place, a dishonest wireless user or a "hacker" may have some access (although limited) to the communication chain. This access creates vulnerabilities, such as denying service attacks, among others. Watermarks / signatures are techniques for adding metadata or unique information to media for signage and / or security purposes. To reduce these susceptibilities of wireless communications, it is desirable to have alternative methods to watermarking / adding signatures to wireless communications.

THE INVENTION At least one stream of user data is processed in layers 2/3, processed in physical layer and processed in radio frequency. A watermark / signature is embedded in at least one of the 2/3 layers, physical layer or radio frequency, producing an embedded wireless communication. Embedded wireless communication is transferred wirelessly. Embedded wireless communication is received and the watermark / signature is extracted from the embedded wireless communication.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is an illustration of a traditional digital communication system Xe transmission. Figure 2 is a water marking illustration of a digital communication transmission system. Figure 3 is a simplified block diagram of water marking of wireless communications. Figure 4 is a simplified flow diagram of water dialing of wireless communications. Figure 5 is a simplified block diagram of a transmission TRU using water dialing for delay transmission diversity. Figure 6 is a simplified block diagram of a reception TRU to be used in the reception of water dialing for delay transmission diversity.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES Hereinafter, a wireless transmission / reception unit (WTRU) includes, but is not limited to, a user equipment, a mobile station, a fixed or mobile subscriber unit, a pager. , a station (STA), or any other type of device capable of operating in a wireless environment. When referred to hereafter, a base station includes, but is not limited to, a Node-B, a site controller, an access point or any other type of interface device in a wireless environment. When referred to hereinafter, a transmission / reception unit (TRU) includes a WRTU, a base station or a wired communication device. With reference to Figure 1, in a traditional digital communication system, the source data is dSOUrce such as binary data. This data could represent digitized speech or image or video signals or binary text or other digital data. This data is sometimes compressed (through a process called source coding) 76 that produces a compressed binary data stream, called dcompressed. • The compressed data is processed by higher OSI layers (for example, HTTP, TCP, IP layers, etc.) 78 producing binary data called dHL- The resulting data is now processed by the OSI layers belonging to the Radio Interface, mainly Layer 3 80, Layer 2 82, Layer 1 84 and Layer O RF 86. As it is called in Figure 1, these are referred to as d3 and d2, if and s0, respectively, d3 and d2 are binary data, whereas Si and So are analog signals. On the receiver side, the processing is carried out in a similar way, but in a reverse order (RF followed by Layer 1, followed by Layer 2, followed by Layer 3, followed by Top Layers and then decompressed). For what follows (excluding the claims), Matos' and 'signals' refer to binary Matos' and ^ analog signals' respectively, unless otherwise specified. Figure 2 shows a modified digital communication link processing chain for embedding watermarks / signatures within the communicated (binary) and / or (analog) signal data. Water marking includes binary watermark data w, a coverage information or signal, an outline / algorithm for embedding the watermark E and data / signal with watermark dw or sw, according to Equation 1. " Sw = £. { s, w} or dw = £. { d, w} Equation (1) The watermark binary data can be generated by digitizing an analog watermark signal. For example, the fingerprint or a signature made by hand is an analog signal, which can be digitized to produce binary watermark data. Since the embedding allows the watermark to communicate with the main source data, the embedding scheme can also be seen as defining (perhaps implicitly) an Embedding Channel within the same source data . As such, it can be said that the embedding scheme defines 'Watermark Handles' or 'Embedded Radio Handles'. If these channels are defined in Layer 1 or in the RF Layer, the corresponding embedded radio channels can also be called ^ Embedded Physical Channels'. The watermark / signature can be embedded within the content 85, 86 (ws), before or after compression 86; can be embedded during the processing of upper layers 88 (wHL); it can be embedded during Layer 3 89 (w3), Layer 2 90 (w2), Layer 1 91 (wl) and Layer O (RF) 92 (wO). Although, what follows, refers to watermarks, you can use signatures instead of watermarks within the same context for wireless communications. Figure 3 is a simplified watermarking diagram of wireless communications and is described in conjunction with Figure 4, which is a simplified flow diagram of watermarking wireless communications. A transmission TRU (TX) 20 receives user data stream (s) to communicate wirelessly to a reception TRU (RX) 22. The user data streams are processed using a single layer processing device 24. TX 2/3 to perform layer 2/3 processing (link / data network). Although the processing of layer 2/3 is illustrated as occurring in the TRU for both the TX 24 and the RX 42, it may alternatively occur in other intermediate nodes of the network. To illustrate, in a universal mobile terrestrial communications (UMTS) system, layer 2/3 processing can occur within a network radio controller, a core network or a Node-B. The processed information of layer 2/3 is processed in a physical layer by means of a physical layer processing device TX 26. The processed information of a physical layer is processed for radio transmission by means of a TX 28 radio frequency processing device (RF) The TRU TX 20 (or alternate network node) receives tokens / keys to produce watermarks (step 46). Tokens / keys are processed by a watermark embedding device 30, which embeds the tokens / keys as a watermark in either "or multiples of layer 2/3, physical layers or RF (step 48). The watermark embedding device 30 can also perform the coding and / or modification of the witnesses / keys, before embedding them, so that they are robust or have a better fit within the data stream (s). The RF communication with the embedded watermark is emitted by an antenna or a set of antennas 32 (step 50) The embedded communication is received over the wireless interface 36 by an antenna or a set of antennas 34 of the TRU 22 receiver (RX) (steps 52) The received communication is processed as RF by a radio frequency processing device RX 38. The communication processed as RF is processed by a physical layer by means of an RF positive physical layer processing RX 40. The processed data of the physical layer is processed by layer 2/3 by means of a layer processing device 2/3 RX 42 to produce the user data stream (s). During the processing of any or multiple of the radiofrequency, physical layer or layer 2/3, the embedded watermark is removed by a watermark extraction device 44 (step 54), thereby producing witness / clavss such as for use in authentication and other purposes of trust, rights, identity, privacy or security. The use of watermarks at lower layers of the Open Systems Interconnection (OSI) model provides potential advantages. Authentication of wireless communications can occur in lower OSI layers and unwanted communications can be identified in these lower layers. As a result, these communications can be discarded or blocked so that they are not processed by higher layers of abstraction that eliminate unnecessary processing at higher layers and free resources. Additionally, since these unwanted communications can not pass into the higher layers, certain attacks on the wireless system, such as the denial of service attacks, can be avoided. Authentication of lower layers also provides additional security for wireless communications. Authentication of lower layers tends to authenticate specific wireless links. As a result, unauthorized individuals can be identified who do not use the appropriate links, which is more difficult and sometimes impossible to achieve at higher levels of abstraction. To illustrate, an authorized user can provide a second user with a username and a code to allow the unauthorized user to access a secure wireless network. If the unauthorized user is not aware that a wireless watermark is required or does not have the hardware / software to generate such a watermark, the unauthorized user will not be allowed access to the secure wireless network, although that user is using a legitimate username and code. INCORRECTED PHYSICAL CHANNELS Two primary techniques are used to create wireless communications with a watermark: first, using a newly defined watermark channel embedded in one or a few physical channels, or second, printing the watermark directly within the or the existing radio channels. In the first technique, a new channel is defined to carry the watermark. These watermarked channels are embedded in radio channels. To illustrate, a technique for producing such a channel consists in slowly modulating differential the amplitude of the radio channel (s) to produce a new watermark channel that coexists with the existing channel (s). The watermarks are carried by these channels. This technique can be modeled in the following way. The existing channel (s) can be seen as a signal of coverage. The watermark is w, an embedding function is E, and the embedded channel is EPC. The EPCH creation techniques are described below. The signal with watermark sw conforms to Equation 2. sw = EEPCH. { S, W} Equation (2) To further enhance security, embedded channels can be encrypted to prevent a dishonest TRU from copying the watermark, if the dishonest TRU somehow knows the embedded channel. These embedded channels can be used to carry data related to the security of the higher OSI layers. To illustrate, the encryption keys and other keys of higher layers are carried by the embedded channel. Other data transported on these channels may include "challenge words" so that a TRU can authenticate itself when challenged by another TRU or the network. Embedded channels preferably occur on a continuous long-term basis; although non-continuous and short-term channels can be used. In some implementations, watermark channels operate on their own, without data being transmitted through the underlying radio channel (s). As a result, it may be necessary to maintain the underlying channel (s), when you do not have any information to transmit. The radio channel can be viewed as a coverage job for the watermark channel. Preferably, the information transmitted by the coverage working channel is typical of the information transmitted by the channel. The existence of non-characteristic data in the channel, such as a long run of zeroes, can draw the attention of a furtive listener to that channel. Said data imitates, preferably, the data currently sent by that channel, which makes it difficult for the furtive listener to find out when coverage data is being transmitted. Alternatively, a random bit pattern can be used in the coverage channel. For encrypted or encrypted channels a random bit pattern can provide adequate security for some implementations. In a military application, the transmitted coverage information may be erroneous information (misinformation). If an enemy unit finds the communication node that transfers coverage data, the enemy can leave the node intact to try to decode the erroneous data or the coverage data. In one embodiment, the generation of appropriate quality coverage data is preferably automated, since manual operations for producing such data may be subject to errors and may be difficult to implement. • Multiple watermark channels can be used to increase the total bandwidth of the composite watermark channel. The use of multiple channels allows information to be transferred from watermarks that have a bandwidth greater than the capacity of a single watermark channel. To further improve safety, when multiple watermark channels are used, the watermark data skips the channels in a predetermined pattern. As a result, a furtive listener who monitors a channel will only be able to access a portion of the watermark information. Embedded radio channels can be used to allow security operations to be performed in a transparent manner for the upper layers. As a result, additional security can be achieved without modifications to the software of the upper layers and applications and without a change in the operational load of these layers.

MARKING OF WATER IN PHYSICAL CHANNELS In the second technique, the watermark is incrusted (print) on the radio channel. To illustrate, synchronization bits or unused bits in radio channels can be modified to effectively carry the watermark in that radio channel. This technique can be modeled in the following way. The existing radio channel (s) can be viewed as one or several coverage signals s. The watermark is w, an embedding function is E, and a secret key is k. The secret key k can be seen as the specific embedding technique of the radio channel, which are described below. The signal with watermark sw conforms to Equation 3. sw = -Ek. { s, w} Equation (3) The watermark signal sw is preferably robust with respect to common signal processing operations, such as filtering, compression or other typical wireless network functionalities. It is also desirable that the watermarked signal Sw be imperceptible. The use of the watermark has no impact on the operation of the wireless system in a perceptible manner. To illustrate, wireless system components that do not know the watermark can process wireless communication without any hardware or software modifications. "<• Additionally, if the technique of watermarking is publicly known, it is desirable that a secure key form be used to ensure the exchange. Both techniques can be used in conjunction with intrusion detection operations. One way to handle intrusion detection is to force the TRUs to re-authenticate with a new authentication key and re-pair with the wireless network. Another method is to manipulate the WEP or other key so that authorized users can re-authenticate, but no TRU can transmit information until it is reauted.

WATER MARKING TECHNIQUES The following are different techniques for watermarking. These techniques can be used with many wireless systems, such as analog, digital, GSM, UMTS W-CDMA (FDD, TDD and TD-SCDMA), CDMA 2000, IEEE 802.11a, b, gyn, IEEE.802.15, IEEE 802.16 , Bluetooth, among others. Although they are described as different techniques, these techniques can be combined in various ways. To illustrate, some wireless systems can use both orthogonal frequency division (OFDM) and code division multiple access (CDMA). Accordingly, a combination of techniques related to OFDM and CDMA can be used.

ERROR CORRECTION CODES Most wireless communication systems use error detection / correction coding. These techniques are adapted to carry watermarks / watermark channel. One technique uses pricking to carry the watermark information. In many wireless systems, punch-in is used to reduce the amount of data bits to a specific number and for other purposes. The punch pattern is changed to indicate a watermark. Each change in the punch pattern represents bits of the watermark. Additionally, the data stream may have added more redundancy than the traditionally used and the additional bits are punched in a pattern to carry the watermark. To illustrate, the data can be encoded at a forward correction rate (FEC) of 1/3 or 1/4 and punctured down at a traditional FEC rate of 1/2. Another technique for transferring a watermark by error correction codes is by initializing a FEC change record with the watermark prior to the channel coding of the data stream. Similarly, a change record to be used in the production of a circular redundancy check (CRC) code is initialized by the watermark. The redundant bits of the FEC code are replaced by bits that are related to the watermark. The transmission and reception TRU will know which redundant bits are being replaced. The FEC queue bits are modified to embed the watermark in those bits. Additionally, the watermark can be masked on FEC outputs, CRC outputs, and convolutional and turbo encoded information. Typically, the watermark is added by module-2 to the FEC output, to the CRC output, and convolutional and turbo encoded information. If the length of the watermark is not the same as the information that is being masked, the watermark can only be applied to a portion of the information / output, filled with zeros, cropped or repeated.

CHANNEL CODING Many wireless channels use the coding of channels for identification, in order to distinguish communications, remove a bias in the sequences of information and for other purposes. .Watermarks can be transported using these codes. In many wireless systems, encryption codes or other codes are used. The watermark is embedded in these codes. Code bits are changed to embed the watermark in the code. Changed bits can be found at the beginning 'of the code sequence, in a segment of the code sequence or in the entire sequence of the code. For significantly coded (highly redundant) communications, the information will be readable, although a small degradation in the signal to noise (SINR) may occur due to the changed bits. Alternatively, the polynomial used to generate some codes is modified to identify the watermark. The values of the polynomial include the information of the watermark. This watermark polynomial can be used for the entire sequence or for a small specified portion, such as in a preamble, in the middle or in the tail. Many wireless systems have flexible / adaptable modulation and coding schemes. The type of modulation and coding varies to identify bits of the watermark. To illustrate, a transmitting TRU can switch between QPSK and 16-QUAM to indicate bits of a watermark. HANDLING MESSAGE BITS Many wireless systems have unused bits / symbols (such as reserved for future use) and unused time slots. Watermark bits are inserted into these bits at unused time intervals. To illustrate, often to match the rates, bits can be added to the data to achieve a specified number of symbols or bits. A watermark is used for these bits instead of padding with zeros or repeating previous bits / symbols. Alternatively, the bits / symbols used are used to carry watermark bits, such as pilot, control and message. At predefined positions within these data, the bits are modified to carry watermark phase rotation symbols, such as the constellation s symbols. These changes occur slowly over time. The change in the phase indicates bits of the watermark.

PHYSICAL / RF MISCELLANEOUS TECHNIQUES Pulse and spectrum forming filters are used in many wireless communications. The coefficients used in the pulse / spectrum formation are modified to carry a watermark. The selection of the set of coefficients to generate the pulse / spectrum shape carries the watermark. A receiver TRU analyzes the pulse / spectrum shape to determine which coefficients were used for the transmission. To illustrate, if N sets of coefficients are used for. To produce allowed pulse / spectrum forms, one can distinguish up to log2 -N bits of a watermark for each set selection of coefficients. It is generally desirable in wireless communications to possess precise transmission modulation to aid accurate demodulation in the receiving TRU. To illustrate, in a QPSK modulation, typically all potentially transmitted constellation values can be viewed as points and are typically found in values of (1 + j, 1-j, -1 + j and -1-j). These values can be compensated for indicating watermark / symbol bits or these values may not form precise points, such as forming small curves instead of a precise point value, identifying watermark bits. In many wireless communication systems including 3GPP and 3GPP2, for a stream of user data stream, there are several possible combinations of physical layer parameters such as FEC type, FEC coding, and modulation type. In 3GPP, these parameters are referred to as a transport format configuration (TFC). The selection of the TFC to transmit a stream of data carries the watermark. RELATED TO RF To indicate bits of a watermark, the frequency of the carrier is adjusted. These adjustments preferably occur at certain time intervals, so that they are distinguished from Doppler changes and other frequency variations of the carrier. The degree of adjustment is an indication of the bits of the watermark. To illustrate, the carrier can be adjusted in increments of hundreds or thousands of Hertz (Hz). Fluctuations are a problem that is dealt with in communications. A watermark can be printed on a signal by creating an artificial fluctuation. To illustrate, a low code code fluctuation is introduced with respect to the frequency of the carrier. The watermark information is effectively modulated by introducing changes in the frequency on the fluctuation. To carry bits of watermarks, the temporal and delay characteristics of a channel are modified. To illustrate, the transmission of information is artificially delayed to indicate the one or more bits of a watermark. In CDMA type systems, such delay may occur in the channelization code. Also, the difference between code delays can be used to indicate bits of a watermark.

RELATED TO THE ANTENNA In 'multi-input / multiple-output (MIMO) communications, the MIMO channel as produced by the various elements of the antenna, can be seen as a function of spatial extent. The transmitted MIMO waveform is modified to indicate bits of a watermark. To illustrate, during the open loop spatial extent, a matrix, such as a Hadamard matrix, is used to carry bits. A specific rotation sequence used in the spatial extension is used to carry the watermark. One method to do this is to use a hardware version of a Shelton-Butler matrix instead of a Hadamard matrix. By switching to a different matrix input or output port, it automatically changes the phase rotation sequence, thus creating a watermark. Another technique for sending a watermark uses polarization of the antenna. The polarization of an antenna or array of antennas varies to modulate bits to provide a watermark. To illustrate, the polarization varies in a pseudo-random synchronized manner. In the diversity of transmission, various coding techniques are used, such as space-time block coding (STBC) and space-frequency block coding (SFBC). The coding of these symbols is modified to carry bits of watermarks. To illustrate, the symbols of each of the other symbol periods may be embedded with a watermark bit by inversion or noninvestment.

DANGER OF DELAY TRANSMISSION In wireless systems, a wireless channel is modified such that a delay profile of a received channel is modified to be the medium that carries the information for a watermark. In a receiver, the watermark is extracted and decoded by an extension of the channel estimate to extract the characteristics of the delay profile of the channel carrying the watermark. The characteristics of a propagation channel 'are used to embed the watermark. As a result, it is very difficult to detect or avoid the watermark if the watermark is not conceived or the recipient is not aware of the technique used. Additionally, this technique allows a receiver who is not aware of a watermark to operate without this additional information being decoded.

Specifically, existing infrastructure teams could still work with this technique. - One modality of this technique is illustrated in the Figures 5 and 6. Figure 5 is a simplified block diagram of a transmission TRU. A diversity transmitter 60 can be any suitable transmitter that includes a provision to transmit on various antennas. Specifically, it should contain two separate transmission chains. The diversity transmitter .60 incorporates a variable (adjustable) delay 64 that is modulated in such a way that it causes the relative delays of the second antenna to be equal to the values of the watermark bits. Although illustrated with two transmit antennas 66, the mode can be extended to any number of antenna elements by the addition of additional delays. A watermark pattern generator 62 produces a watermark sequence, such as a pseudorandom sequence. The delay device 64 delays the signal transmitted on an antenna element relative to a reference antenna element, in response to the pattern of watermarks. To illustrate, the delay can be controlled in multiples of a chip or symbol, and is preferably adjusted such that the average delay d is greater than the (or some other multiple of) channel coherence bandwidth. Transmission antennas 66 are sufficiently uncorrelated to ensure that the signals exhibit relative diversity to one another. This can be achieved by proper separation of the antennas, the use of polarization antennas, or directional antennas. Preferably, the antennas are separated to a value greater than twice the wavelength of the carrier, although a smaller separation can be used. Although it is illustrated that this technique is used in multiple antennas, it can be used in a single antenna. Both delayed and non-delayed data streams can be combined and broadcast on a single antenna. In such a configuration, the delay between the currents is selected so as to allow a distinction of the two signals. As a result, the second current creates an artificial multi-path with respect to the receiver TRU. Specifically, the delay is adjusted such that the average delay d is greater than the (or some other multiple of) channel coherence bandwidth. Figure 6 illustrates a receiver TRU. The receiving antenna 68 or set receives the wireless transmission. The device for channel estimation or road search 70 (called channel estimation hereafter) is a technique used to identify the derivation coefficients of the channels or delay trajectories. The extension in time of delay trajectories is referred to as the channel delay extension. A watermark sequence generator 72 is used to locally generate a private copy of the reference watermark (or key) to compare (or correlate!) Against the received watermark. A local private copy can also be derived by some other means, for example, from a copy that is stored in a subscriber information module (SIM) card for a global system for mobile telephones (GSM). A correlator 74 is used to compare the received watermark (within the channel estimate) with the local private copy. If the correlation is high (above a specified threshold, for example, >; 0.9), it is considered that the watermark is intended for the recipient. Although the figures of the application are illustrated as separate elements, these elements can be found on a single integrated circuit (IC), such as an application-specific integrated circuit (ASIC), multiple ICs, discrete components or a combination of discrete components and the IC. Although the features and elements of the present invention are described in the preferred embodiments in particular combinations, each feature or element can be used alone without the other features. -, and elements of the preferred embodiments or in various combinations with or without other features and elements of the present invention.

Claims (43)

1. CLAIMS 1. Method is characterized in that it comprises: performing, on at least one user data stream, a 2/3 layer processing, a physical layer processing and a radiofrequency processing; embed a watermark / signature on at least one of layer 2/3, physical layer or radio frequency, thus producing an embedded wireless communication; wirelessly transfer embedded wireless communication; and receive the embedded wireless communication and extract the watermark / signature from the embedded wireless communication. Method according to claim 1, further characterized in that it comprises receiving tokens / keys and processing the embedded tokens / keys for use to embed the watermark / signature in the embedded wireless communication. 3. Method according to claim 1, characterized in that the embedded watermark / signature is used to authenticate a communication prior to any substantial processing in an OSI layer superior to the -processing. of layer 2/3, physical layer and radiofrequency. Method according to claim 1, characterized in that the embedding of the watermark / signature results in at least one physical channel carrying the user data stream and a watermark channel carrying brand information of the user. water / signature embedded within at least one physical channel. 5. Method according to claim 4, characterized in that the channel with embedded watermark carries data related to the security coming from OSI layers higher than the processing of layer 2/3, the physical layer and radio frequencies. Method according to claim 4, characterized in that the watermark channel is encrypted. Method according to claim 4, characterized in that the at least one physical channel is maintained during periods in which there is no user data to be sent over at least one physical channel such that the watermark channel is maintained . Method according to claim 1, characterized in that the watermark / signature is printed on at least one physical channel. Method according to claim 1, characterized in that the watermark / signature is embedded using error detection coding / error correction. Method according to claim 1, characterized in that the watermark / signature is embedded using encryption / channeling codes. Method according to claim 1, characterized in that the watermark / signature is embedded using bits of the user data stream. Method according to claim 1, characterized in that the watermark / signature is embedded by adjusting the pulse / spectrum shapes. Method according to claim 1, characterized in that the watermark / signature is incrusted by adjusting the modulation. Method according to claim 1, characterized in that the watermark / signature is embedded by adjusting at least one of the following: carrier frequency, fluctuation and delay / time characteristics. Method according to claim 1, characterized in that the watermark / signature is incrusted by adjusting the polarization of the antenna. "" 16. Method according to claim 1, characterized in that the watermark / signature is adjusted for MIMO communications using a phase rotation sequence. Method according to claim 16, characterized in that the phase rotation is performed using Shelton-Butler matrix hardware and changing input / output ports. 18. Method according to claim 1, characterized in that the watermark / signature is incrusted by, a variation of the delay between a plurality of transmission antennas. 19. Method of compliance with claim X, characterized in that the processing of layer 2/3, the processing of the physical layer and the processing of radio frequencies of user data are carried out by means of a transmission / reception unit. Method according to claim 1, characterized in that the processing of the layer 2/3, the processing of the physical layer and the processing of the radiofrequencies of user data are carried out by means of a transmission / reception unit and at least one node of the network. 21. Transmission / reception unit (TRU) characterized in that it comprises: means for performing a layer 2/3 processing, physical layer processing and radiofrequency processing on at least one user data stream.; means for embedding a watermark / signature in at least one of layer 2/3, the physical layer or the radio frequency, thus producing an embedded wireless communication; means for wirelessly transferring embedded wireless communication. 22. TRU according to claim 21, further characterized in that it comprises receiving tokens / keys and processing the embedded tokens / keys for use to embed the watermark / signature in the embedded wireless communication. 23. TRU according to claim 21, characterized in that the embedded watermark / signature is used to authenticate a communication prior to any substantial processing in an OSI layer greater than the processing of layer 2/3, the physical layer and radiofrequency 24. TRU according to claim 21, characterized in that the embedding of the watermark / signature results in that at least one physical channel carries the user data stream and that a watermark channel carries brand-name information. water / signature embedded within at least one physical channel. 25. TRU according to claim 24, characterized in that the channel with embedded watermark carries data related to the security coming from OSI layers higher than the processing of layer 2/3, of the physical layer and of radio frequency. 26. TRU according to claim 24, characterized in that the watermark channel is encrypted. 27. TRU according to claim 24, characterized in that the at least one physical channel is maintained during periods in which there is no user data to be sent on at least one physical channel such that it channel. Watermark is maintained. 28. TRU in accordance with. Claim 21, characterized in that the watermark / signature is printed on at least one physical channel. 29. TRU according to claim 21, characterized in that the watermark / signature is embedded using error detection coding / error correction. 30. TRU according to claim 21, characterized in that the watermark / signature is embedded using encryption / channeling codes. 31. TRU according to claim 21, characterized in that the watermark / signature is embedded using bits of the user data stream. 32. TRU according to claim 21, characterized in that the watermark / signature is embedded by adjusting the pulse / spectrum shapes. 33. TRU according to claim 21, characterized in that the watermark / signature is incrusted by adjusting the modulation. 34. TRU according to claim 21, characterized in that the watermark / signature is embedded by adjusting at least one of the carrier frequency, fluctuation and delay / time characteristics. 35. TRU according to claim 21, characterized in that the watermark / signature is incrusted by adjusting the polarization of the antenna. 36. TRU according to claim 21, characterized in that the watermark / signature is adjusted for MIMO communications using a phase rotation sequence. 37. TRU according to claim 36, characterized in that the phase rotation is performed using Shelton-Butler matrix hardware and changing input / output ports. 38. TRU according to claim 21, characterized in that the watermark / signature is incrusted by a variation of the delay between a plurality of transmit antennas. 39. TRU according to claim 21, characterized in that the processing of the 2/3 layer, the processing of the physical layer and the radio frequency processing of user data are carried out by means of a transmission / reception unit. 40. TRU according to claim 21, characterized in that the processing of layer 2/3, the processing of the physical layer and the radio frequency processing of user data are carried out by means of a transmission / reception unit and at least one node of the network. 41. TRU in accordance with claim 21, characterized in that the TRU is a wireless TRU. 42. TRU according to claim 21, characterized in that the TRU is a base station. 43. TRU according to claim 21, characterized in that an integrated circuit comprises the means to perform, the means for embedding and the means to transfer wirelessly.