MXPA00009731A - Mobile station employing crc verification using decoding reliability and methods therefor - Google Patents

Abstract

Various methods are disclosed for operating a mobile station of a type that receives a digital traffic channel, such as an IS-136 compliant mobile station. One of the methods includes steps of (a) receiving a signal from a forward traffic channel and decoding the received signal using a first predetermined decoding technique to generate a first bit error rate (BER);(b) decoding the received signal using a second predetermined decoding technique to generate a second BER;(c) comparing the first BER to the second BER;and (d) declaring the received signal to be one of a FACCH message or user data depending on a result of the comparison. The step of declaring may include a preliminary step, for a case where the step of comparing indicates that the received signal is a FACCH message, of first verifying that the received signal contains a valid FACCH message type.

Description

MOBILE STATION THAT USES CRC VERIFICATION USING RELIABILITY OF DECODIFICATION ION AND METHODS FOR THE SAME FIELD OF THE INVENTION This invention relates in general to telecommunications devices such as radiotelephones and, in particular, to radiotelephones or mobile stations operating in accordance with a digital data transmission format and protocol.

BACKGROUND OF THE INVENTION In a modern digital telecommunications system, based on an interconnection standard known as IS-136, a data field received in a digital data channel (DDCH) includes an ordinary data block, transferred (DATA) or a control message and monitoring, specifically known as the fast associated control channel (FACCH). The IS-136 standard is one based on time division / multiple access (TDMA) and uses a slotted frame structure for a channel Ref: 123738 forward (base station to the mobile station) and a reverse channel (mobile station to the station) base ) . Referring briefly to Figure 3, it can be seen that a traffic channel may contain user information such as DATA, the FACCH, and a slow associated control channel (SACCH). As defined in IS-136, the traffic channel can contain at any given time only the information of the user or the FACCH, not both simultaneously. DATA and FACCH use different encoding / decoding methods (and cyclic redundancy checks (CRCs)). The DATA may be data bits, such as facsimile data or data from the computer network, or may represent encoded voice data. The FACCH is defined as a channel used to signal the exchange of messages between the base station and the mobile station. Reference can be made to IS-136.2, Rev. A., 12/2/96, Section 2.7.3.1.1 (Fast Associated Control Channel (FACCH)), and subsections 2.7.3.1.1.1 to 2.7.3.1.1.5 contained therein, for a description of the FACCH that is of most interest for this invention.

In general, the FACCH data is protected against errors by means of a 1/4 proportion convolutional code, and 49 data bits in a FACCH word are appended with a 16-bit CRC to detect the presence of channel errors . Another intended purpose for the 16-bit CRC was originally established to provide a mechanism for distinguishing FACCH data from voice data. However, this latter purpose has been found to be inadequately met. A general problem has arisen of how to more accurately detect the data (and the data type) in the process of decoding the received signal. Typically, the data is decoded using one or more decoding methods, and then if a data passes the integrity test (typically one using a CRC) the decoded bits become available for further processing. If the CRC check fails, then another method can be tried for the decoding process, and another CRC test is performed. More particularly, it has been determined that a block of data received, occasional, with certain combinations of bits, can erroneously pass the decoding process of FACCH, and also the verification of the FAC CRC. This failure mode is due to the rather limited length of the CRC field. In this case, the data may be lost, since it was erroneously detected that it is a FACCH message from the base station. In more detail, a received block is typically decoded first as the FAC. It has been found, however, that the FACCH CRC check will sometimes happen with some combinations of bits found in ordinary data blocks (for example, coded voice data). In this case the data block is detected (erroneously) as a FACCH message, and the ordinary data can be completely lost. The presumed FACCH message is then further processed and subsequently detected as invalid (wrong type). Also very problematic is the case where the presumed FACCH message (effectively the data) corresponds to one of the plurality of valid FACCH messages, thereby introducing a possibility that the mobile station may operate in an erroneous manner, in any case , the intended ordinary data block has been lost.

There may be an ability to retransmit the DATA (for example if no acknowledgment of the reception by the mobile station is detected at the base station), especially in some circumstances where the DATA is considered vital. However, this could result in the generation of a loop or endless cycle if the DATA is again mistakenly detected as a FACCH message in the mobile station. The final result could be the suppression of a DATA call. The same failure mechanism can also be found on the side of the base station, and a DATA call can be suppressed when the DATA is being transferred to the base station from the mobile station. Similar failure mechanisms have been observed with voice encoded by VSELP, where a received FACCH message was erroneously detected as a voice due to the CRC verification that was passed. To summarize, and by way of example, in a mobile station based on the IS-136 specification, the FACCH data is well protected against errors induced by the channel (convolution coding of 1/4 ratio), and the decoding process You can correct several erroneous bits in the data field. Typically, but not necessarily, the mobile station first tries to decode the received signal as a FAC message .. However, if the decoded data block is not a FACCH message (for example, this is an ordinary DATA), the decoding process FACCH attempts to correct several (typically 30-65) bits in the data field. In most cases the CRC check will fail. However, some random bit sequences in the decoded (ordinary) DATA can also produce a passing CRC check. The decoding process then wrongly assumes that the received bits represent a FACCH message that has a high proportion of bit errors (Poor RF signal), and the DATA is lost. The presumed FACCH message will then typically be subsequently determined to be invalid, although in some cases the received bit sequence may be decoded to a valid FACCH message, resulting in a possibility of wrong mobile station operation.

OBJECTIVES AND ADVANTAGES OF THE INVENTION Thus, a first objective and advantage of this invention is to provide an improved method for receiving information from a traffic channel in one or both of a mobile station and a base station of a radio telecommunications system. A further objective and a further advantage of this invention is to provide a method for distinguishing the received control messages, from the received data, such as the computer data or the encoded voice data. Yet another object and further advantage of this invention is to provide a method for distinguishing received FACCH messages from received user data, such as computer data or encoded voice data.

BRIEF DESCRIPTION OF THE INVENTION The above problems and other problems are overcome and the objectives and advantages are realized by methods and apparatuses according to the embodiments of this invention. In accordance with the teachings of this invention, a decoding process is carried out with all possible decoding methods. If the CRC verification happens with more than one decoding method, then an additional study of the decoding process is performed to determine which resulted in a correct CRC verification. According to one embodiment of this invention, the receiver circuitry typically first decodes a received signal as a FACCH message and obtains a first BER, and then also attempts to decode the same input signal (received bits) as ordinary or user DATA. (DATA in a digital data channel and voice in a digital voice channel). In the latter case the decoding process and CRC verification will also pass, because the data received was effectively an ordinary DATA block. The decoding process then corrects, typically, zero or only a few erroneous bits (induced by a poor radio channel) and it finds that a second BER is significantly smaller than the first BER that was obtained when the received signal was decoded assuming a FAC message. The data type (ordinary FACCH or DATA (user) is then selected based on the first BER obtained when the received signal was decoded as a FACCH message and the second BER obtained when the received signal was decoded as ordinary DATA. it is assumed that the lower BER indicates the true data type of the received signal More particularly, in one embodiment of this invention, a method for operating a mobile station of a type that receives a digital traffic channel, such as a mobile station complying with time division, multiple access ISIS (TDMA) .The method includes the steps of (a) receiving a signal from a forward traffic channel and decoding the received signal using a first technique default decoding to generate a first bit rate or bit error ratio (BER); (b) decoding the received signal using a second predetermined decoding technique to generate a second BER; (c) compare the first BER to the second BER; and (d) declaring the received signal as one of a FACCH message or a user data depending on the result of the comparison. The declaration step may include a preliminary step, for a case where the compare step indicates that the received signal is a FACCH message, to first verify that the received signal contains a valid FACCH message type. In other embodiments of this invention, useful in one or both of a mobile station and a base station, a combination of the signal quality indications, such as the BER and CRC validity indicators, are used to detect a type of data that is received, and to declare that the data received from a message related to control and supervision (such as the FACCH), or is a user DATA or encoded voice information. In general, the teachings of this invention apply to so-called DATA and voice calls.

BRIEF DESCRIPTION OF THE DRAWINGS The features of the invention described above and others are made more apparent in the following detailed description of the invention, when read in conjunction with the accompanying drawings, wherein: Figure 1 is a block diagram of a mobile station that is constructed and operated in accordance with this invention; Figure 2 is an elevation view of the mobile station shown in Figure 1, and which further illustrates a cellular communication system to which the mobile station is bidirectionally coupled through wireless RF connections; Figure 3 is a very high level description of a conventional traffic channel organization; Figure 4 is a logical flow diagram of a method according to a first embodiment of the teachings of this invention; Figure 5 is a logical flow diagram of a method according to a second embodiment of the teachings of this invention; Figure 6 is a logical flow diagram of a method according to a third embodiment of the teachings of this invention; and Figure 7 is a logical flow diagram of a method according to a fourth embodiment of the teachings of this invention.

DETAILED DESCRIPTION OF THIS INVENTION Reference is first made to Figures 1 and 2 to illustrate a wireless user terminal or mobile station 10, such as, but not limited to a cellular radiotelephone or personal communicator, which is suitable for practicing this invention. The mobile station 10 includes an antenna 12 for transmitting signals to, and for receiving signals from, a base site or base station 30. the base station 30 is a part of a cellular network comprising a Base Station / Mobile Switching Center function / Interleaving (BMI) 32 including a mobile switching center (MSC) 34. The MSC 34 provides a connection to wired trunk lines when the mobile station 10 is involved in a call, which may be a voice call or a call DATA . The mobile station includes a modulator (MOD) 14A, a transmitter 14, a receiver 16, a demodulator (DEMOD) 16A, and a controller 18 that provides signals to, and receives signals from, the transmitter 14 and the receiver 16, respectively. These signals include the signaling information according to the air interconnection standard of the applicable cellular system, and also the data generated by the voice of the user and / or the user. The air interconnection standard is assumed for this invention to use a digital channel (such as that found in IS-136) that is capable of transporting a messaging signal, such as FACCH, as well as "ordinary" or "ordinary" data. "user" that is assumed to include DATA such as facsimile or computer data (e.g., Internet data packets having a TCP / IP format), or voice data obtained from an appropriate voice coder. However, the teachings of this invention are not intended to be limited solely to use with a mobile station compatible with IS-136, or for use only in TDMA-type systems. In fact, the teachings of this invention can also be applied to at least some CDMA-type systems, as well as to various modes of other types of TDMA systems. It is understood that the controller 18 also includes the circuitry required to implement the audio and logical functions of the mobile station. For example, the controller 18 may be comprised of a digital signal processing device, a microprocessor device, and various analog-to-digital converters, digital-to-analog converters, and other support circuits. The signal processing and control functions of the mobile station are assigned among these respective capability devices. For purposes of this invention, the controller 18 is assumed to contain or implement at least one decoder 18a for the encoder A received in bit blocks. A decoder 18a could be used to decode the signal using two or more selected decoding techniques, as described in detail below, or multiple separate decoders could also be used for this purpose. A user interface includes a conventional headset or loudspeaker 17, a conventional microphone 19, a display 20, and a user input device, typically a keyboard 22, all of which are coupled to the controller 18. The keyboard 22 includes the keys conventional keys (0-9) and reclaimed keys (# / *) 22a, and other keys 22b used to operate the mobile station 10. These other keys 22b may include, for example, a send key (SEND), various keys Menu shift and soft keys, and an energy key (PWR). The mobile station 10 also includes a battery 26 for energizing the various circuits that are required to operate the mobile station. The mobile station 10 also includes various memories, collectively shown as the memory 24, wherein a plurality of constants and variables are stored which are used by the controller 18 during the operation of the mobile station. The memory 24 may be an external memory device as shown, or may be integrated within the controller 18. For example, the memory 24 stores the values of various parameters of the cellular system and the number assignment module (NAM). An operation program for controlling the operation of the controller 18 is also stored in the memory 24 (typically in a ROM device). In accordance with one aspect of this invention, the memory 24 is used to store a received block of data from the forward traffic channel, and to store also first and second BERs, as described below, as well as first and second CRCs, also as described later. In a first aspect of this invention, the above problems are overcome by decoding a received signal as a FACCH message, and by determining whether the received data represents a valid control message. If the received data does not decode as a valid FACCH message, then it can be assumed that an ordinary data block has been received. The processing of the ordinary data block can then proceed according to the highest levels of data handling. However, it will remain as a possibility that the block could be mistakenly detected as a valid FACCH message, even in the case where the block did indeed contain an ordinary data block. Therefore, an invalid behavior can be generated in the mobile station 10 (such as an erroneous or inappropriate operation of the controller 18) and / or a block of data will be lost, causing a possible error loop in the handling portion of the data transfer data.

According to a currently most preferred embodiment of this invention, mobile station 10 decodes the received data block as a FACCH message and as ordinary DATA. In some cases, the result of the decoding process is such that the CRC check will pass for both decoding methods. In such a case, it is more likely that the wrong decoding procedure has modified several bits in the received block (attempted error correction) while the correct decoding procedure has not modified any or only a few bits in the slot to compensate for the normal errors induced by the channel. The proportion of received signal bit errors (BER) can therefore be approximated as a function of the number of bits of the corrected decoding process. The method can then determine what type of data the received block actually contained (FACCH or user DATA) by selecting the decoding method that provides the lowest BER with the received signal (bit block).

Someone can also detect the accuracy of the FACCH message as well, in the case where the FACCH decoding procedure results in a lower BER (fewer corrected bits). In more detail, and with reference now to Figure 4 for a first embodiment of this invention, in Block A the mobile station 10 receives and stores in the memory 24 a data block coming from the forward traffic channel, and executes a procedure of predetermined decoding to first decode the received data signal (bit block) as a FACCH message (using, for an IS-136 example, the procedures described in Section 2.7.3.1.1). During the decoding of the data block, using the 1/4 ratio convolutional decoding procedure, the verification and correction of specified error is achieved, and a first indication of received signal quality, such as BER (BERi), it is obtained and stored in memory 24 (see Figure 1), as is another indication of received signal quality, such as CRC (CRCí). In Block B, the stored data block is again decoded, but this time using the decoding procedure specified for the user / voice DATA. The final result is the generation of a second indication of received signal quality, such as BER (BER2), which can also be stored in memory 24 or used immediately in the execution of the next block C. A second CRC is obtained (CRC2 ) and is also stored in memory 24. In Block C, controller 18 compares BER-. and BER2. If BERi is not less than (or equal to) BER2, then the control goes to block D where a check is made to determine if CRC2 passes. If so, then it is assumed in Block E that the received signal is user DATA, and further processing of the user DATA is performed as required. If the CRC check in Block D indicates that the CRC does not pass, then it is assumed that the received signal is invalid and too corrupted to be used. That is, if the block reaches Block F, the test in Block C will find that the first BER, for example, that obtained when the received signal was decoded assuming a FACCH message, indicated a higher number of bit errors than the number obtained when the received signal was decoded assuming a DATA / voice signal, still the CRC obtained when the signal was decoded as DATA / voice was not adjusted to the CRC value that forms a part of the received data signal. When in Block C the controller 18 compares BERi and BER2 and finds that BERi is smaller (or equal to) BER2, then the control passes instead to Block G where a check is made to determine if CRCí happens (for example, the CRC obtained when the signal was decoded as FACCH is adjusted to the CRC value that forms a part of the received data signal?). If so, then control passes to Block H (optional) where a step is performed to determine if the received signal contains a valid FACCH message type. If not, then the control goes to Block D, as it does also if the CRC test in Block G fails. In Block D a check is made to observe if the CRC2 is good, as previously described. If the test in Block H (optional) passes (or the test of Block G happens if Block H is not used), then control passes to Block I where it is assumed that the received signal is a FACCH message, and is performed the subsequent processing of the received signal as a FACCH message is carried out. The invention has been described above in the context of the use of BER as the indicator of the quality of the signal. However, the teaching of this invention is not limited to use only with the BER, since the proportion of symbol errors (SER) could also be used, preferably in combination with the BER. Whichever quality measure is used, it is desirable that it be an indicator of the number of erroneous, possibly corrected, bits that occur in the block of bits received during the execution of the selected decoding process. With reference to Figure 5, in Block A, the received data signal (for example, the bit blocks) is first decoded as FACCH, and the BERi is derived and stored in memory 24. In Block B the indicator CRC validity that resulted from the decoding step of Block A is verified to determine if it meets a pass / fail criterion. If the CRC indicator indicates a fault condition, control passes to Block C, where the stored data block is again decoded, but this time using the decoding procedure specified for the user's DATA / voice. Although not specifically required later in the method, one result of this decoding step is the generation of BER2 which can be stored in memory 24. In Block D the CRC validity indicator that resulted from the decoding step of the Block C is verified to determine if it meets the pass / fail criteria. If the CRC validity indicator indicates a fault condition, control passes to Block E where the data block is declared as invalid and can typically be erased or overwritten. If the CRC validity indicator indicates a passing condition in Block D, the control then passes to Block F where the decoded data block is declared as DATA / voice to the subsequent processing routine. Returning to Block B, if the CRC validity indicator that resulted from the decoding step of Block A indicates rather a pass condition, the control goes to Boke G to compare the BER to some threshold level (LEVELi). Yes BER. is less than the threshold, then control passes to Block H where the decoded data block is declared as a FACCH message for the additional processing routine. If BERi is not less than the threshold, then the control passes instead to Block C where, as described above, the stored data block is again decoded, but this time using the decoding procedure specified for the user's DATA / voice. Reference is now made to the embodiment shown in Figure 6. Blocks A, B, C, D, E and F operate as described above with reference to Figure 5. In Block G the BERj is compared to a level of threshold (referred to as LEVEL; to distinguish it from the threshold described in Figure 5). LEVEL2 is preferably defined as zero or some small value. If BERi is greater than the threshold, then control passes to Block H where the stored data block is again decoded using the decoding procedure specified for the user's DATA / voice. The final result is the generation of BER2, which is stored in memory 24. In Block I the validity indicator of CRC that resulted from the decoding step of Block H is verified to determine if it meets a pass / fail criterion . If the CRC validity indicator indicates a pass condition, control passes to Block J to perform a comparison to verify if BER2 is greater than BERi. If so, control passes to Block F where the decoded data block is declared as DATA / voice for subsequent processing routines. If in Block G it is found that BERi is not greater than the LEVEL2 threshold (that is, zero or only a few bit errors are detected during the FACCH decoding), or if the CRC validity indicator fails the test in the Block I, or if in Block J it is found that BER2 is not greater than BERi, then control passes to Block K where the decoded data block is declared as a message FACCH for subsequent processing routines. Reference is now made to the modality shown in Figure 7. It can be noted at the outset that this modality does not require the use of the BER indications, but rather relies solely on CRC validity indicators (eg, the computed CRC from the decoded block of bits is equal to the expected CRC value found in the CRC field of the received signal?). It is also noted that in the voice channel it is preferred to decode the received signal (for example, using only class 1 bits) as the voice (or FACCH) using the convolutional polynomial defined in the applicable specification (for example IS-136). In the DATA channel (switched circuit) it is preferred to decode the signal as DATA. When using the same convolutional polynomial (in the Viterbi decoder), but a different number of bits are (de) coded and the CRC is calculated on different (number of) bits. Also, the CRC field length (for example, the number of CRC bits) is different, so the CRC polynomial is also different for voice and DATA. For example, the voice has a CRC of 7 bits and DATA has a CRC field of 16 or 24 bits. The speech encoding methods VSELP and EFR also have a different number of encoded bits. Returning again to Figure 7, in Block A the received data signal (for example, the bit block) is first decoded as FACCH. In Block B the CRC validity indicator that resulted from the decoding step of Block A is verified to determine if it meets the pass / fail criteria. If the CRC validity indicator indicates a fault condition, control passes to Block C where the stored data block is once again decoded, but this time using the decoding procedure specified for the DATA / voice user. In Block D the CRC validity indicator that resulted from the decoding step of Block C, is verified to determine if it meets the pass / fail criteria. If the CRC validity indicator indicates a fault condition, control passes to Block E where the data block is declared as invalid and is typically erased or overwritten. If the validity indicator CRC indicates a passing condition in Block D, the control passes instead to Block F where the decoded data block is declared as DATA / voice for the additional processing routines. These steps are very similar to those described in Figure 5, with the exception of the single use of the CRC indicators, and not the BER values. If the CRC test passes to Block B, then control passes to Block G where the validity of the decoded data as a FACCH message is verified (eg, does the decoded data represent a valid FACCH message type?). If in Block H it is found that the FACCH data is valid, then the control passes to Block I where the decoded data block is declared as a FACCH message for the additional processing routines. If it is found rather in Block H that the FACCH data is invalid, then control passes to Block C, and processing continues as described above. Although described in the context of the preferred embodiments, it should be noted that a number of modifications to these teachings can occur for a person skilled in the art. For example, certain blocks in the flow diagrams could be executed in a different order from the one shown, and other steps could also be inserted, while also achieving the same desired result. For example, Blocks A and B of Figure 4 could be reversed, such as Block G and (Optional Block H), and / or the operation of Block F that could result in the generation of no data flags. received with a request for retransmission of data, if available. As previously mentioned, the teachings of this invention are also not limited to the reception of the front channel in a TDMA format, since a CDMA or some other format could also be used. It should also be noted that the teachings of this invention can be extended to the use of three or more decoding schemes and the generation and comparison of three or more quality indicators of received signal such as BERs, in a case where a transmitted signal could contain three or more different types of information that will be correctly identified and distinguished for further processing. It should also be noted that the BER gives the desired information since the number of bit errors in the received data is of greater interest, while an averaged value of a number of errors over multiple received slots is of little or no interest. As such, the expression "BER" has been used for convenience to describe the number of erroneous bits in the received signal (the last received slot), and does not need to indicate a "proportion" of errors per s e. According to the teachings of this invention, the erroneous bits (high BER) are mainly induced by the use of the decoding method (erroneous) (for example, trying to decode a FACCH message using the decoding technique designed for DATA / voice). In this context, the value of a BER signal quality indicator or similar that was found to be lower than some threshold value could be considered "better" than another BER or signal quality indicator that was found to be greater than the threshold value, while conversely the value of a BER signal quality indicator or similar that was found to be greater than some threshold value could be considered as "worse" than another signal quality indicator or BER that is found is less than the threshold value. It should also be remembered that the teachings of this invention can be used in the mobile part of the wireless communication network, for example in a mobile station such as a cell phone, a personal communicator, or a modem (modulator-demodulator) wireless; or it may be used in the fixed part of the wireless communications network, such as in a base station or cell site receiver (which are considered as wireless devices for purposes of this invention). The teachings of this invention can thus also be used in the moving and fixed parts of the communication network. In view of the above comments, and also in view of the various possible embodiments of the invention that were described above, those skilled in the art should appreciate that while the invention has been particularly shown and described with respect to these preferred embodiments, it may be make various changes in form and detail to the teachings of this invention, without departing from the scope and spirit of the invention.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Claims (30)

CLAIMS Having described the invention as above, the content of the following claims is claimed as property:

1. A method for operating a wireless device, characterized in that it comprises the steps of: receiving a signal and decoding the received signal using a first predetermined decoding technique, to generate a first indication of received signal quality; decoding the received signal using a second predetermined decoding technique to generate a second indication of received signal quality; and declaring the received signal as a first type of received signal or a second type of received signal, depending on a value of the first and second indications of the quality of the received signal, and also directing the processing of the decoded received signal with base whether the received signal is declared as the first type of the received signal or the second type of the received signal.

2. A method according to claim 1, characterized in that the first and second quality indications of the received signal are each, an indication of a number of bit errors that occur during the decoding process.

3. A method according to claim 1, characterized in that the first type of received signal is a type of control and monitoring message, and wherein the second type of received signal carries data generated by a user or intended for a user.

4. A method according to claim 1, characterized in that the first type of received signal is a type of Fast Associated Control Channel (FACCH), and wherein the second type of received signal is a DATA type (data).

5. A method according to claim 1, characterized in that the first type of received signal is a type of Fast Associated Control Channel (FACCH), and wherein the second type of received signal is a type of coded voice.

6. A method according to claim 1, characterized in that the device is one of a mobile station or a base station.

7. A method for operating a mobile station, characterized in that it comprises the steps of: receiving a signal from a forward traffic channel and decoding the received signal using a first predetermined decoding technique to generate a first BER; decoding the received signal, using a second predetermined decoding technique to generate a second BER; compare the first BER to the second BER; and declare the received signal as one of a FACCH message or a user data, depending on the result of the comparison.

8. A method according to claim 7, characterized in that the declaration step includes a preliminary step, for a case where the comparison step indicates that the received signal is a FACCH message, or first verifying that the received signal contains a message type FACCH valid.

9. A method for operating a wireless device, characterized in that it comprises the steps of: A) receiving a signal and decoding the received signal using a first predetermined decoding technique, to generate a first indication of received signal quality and a second indication of quality of received signal; B) determine if the second indication of received signal quality indicates one of a pass / fail condition; C) if a pass condition is indicated, the first indication of the quality of the received signal is compared with a threshold value; and D) if the first indication of the quality of the received signal is better than the threshold value, it is stated that the received signal is a first type of received signal; even more E) if a pass condition is not indicated in Step C, or if the first indication of received signal quality is found to be no better than the threshold value in Step D, the received signal is decoded using a second predetermined decoding technique for generating a third indication of received signal quality; F) determine if the third indication of received signal quality indicates a pass / fail condition; G) if a passing condition is indicated in Step F, it is declared that the received signal is of a second type of received signal; even more H) if a fault condition is indicated in Step F, the received signal is declared invalid.

10. A method according to claim 9, characterized in that the first indication of received signal quality is a Bit Error Ratio (BER), and wherein the second and third received signal quality indications are each a Verification Indicator. of Cyclic Redundancy (CRC).

11. A method according to claim 9, characterized in that the first type of received signal is a type of control and supervision message, and wherein the second type of received signal transports data generated by a user or designed for a user.

12. A method according to claim 9, characterized in that the first type of received signal is a type of Fast Associated Control Channel (FACCH), and wherein the second type of received signal is one of a DATA type or one of a kind of coded voice.

13. A method according to claim 9, characterized in that the device is one of a mobile station or a base station.

14. A method for operating a wireless device, characterized in that it comprises the steps of: A) receiving a signal and decoding the received signal using a first predetermined decoding technique to generate a first indication of received signal quality and a second indication of received signal quality; B) determine if the second indication of received signal quality indicates one of a pass / fail condition; C) if a pass condition is indicated, the first indication of received signal quality is compared to a threshold value; and D) if the first indication of received signal quality is worse than the threshold value, the received signal is decoded using a second predetermined decoding technique to generate a third indication of received signal quality and a fourth indication of signal quality received; E) it is determined if the fourth indication of received signal quality indicates a pass / fail condition; if a pass condition is indicated, the first indication of received signal quality is compared to the third indication of received signal quality; and F) if the first indication of received signal quality is not worse than the third indication of received signal quality, or if the first indication of received signal quality is not worse than the threshold value in Step D, or the fourth indication of received signal quality indicates a fault condition in Step E, then it is declared that the received signal is a first type of received signal; G) if a pass condition is not indicated in Step B, the received signal is decoded using the second predetermined decoding technique to generate the third indication of received signal quality and the fourth indication of received signal quality; H) It is determined if the fourth indication of received signal quality indicates a pass / fail condition; I) if a pass condition is indicated in Step H, or if the first indication of received signal quality is determined to be worse than the third indication of signal quality received in Step F, it is declared that the received signal is a second type of received signal; even more J) if a fault condition is indicated in Step H, it is declared that the received signal is not valid.

15. A method according to claim 14, characterized in that the first and third indications of received signal quality are each, a Bit Error Ratio (BER), and wherein the second and fourth signal quality indications received are each a one indicator of Cyclic Redundancy Verification (CRC).

16. A method according to claim 14, characterized in that the first type of received signal is a type of control and monitoring message, and wherein the second type of received signal transfers data generated by a user or intended for a user.

17. A method according to claim 14, characterized in that the first type of received signal is a type of Fast Associated Control Channel (FACCH), and wherein the second type of received signal is one of a kind DATA or a type of coded voice.

18. A method according to claim 14, characterized in that the device is one of a mobile station or a base station.

19. A method for operating a wireless device, characterized in that it comprises the steps of: A) receiving a signal and decoding the received signal using a first predetermined decoding technique, to generate decoded data and a first indication of received signal quality; B) determine if the first indication of the quality of the received signal indicates one of a pass / fail condition; C) if a pass condition is indicated, the decoded data is checked to determine if it contains a valid data type; D) if so, it is declared that the received signal is of a first type of received signal; even more E if the first indication of received signal quality indicates a fault condition in Step B, or if the verification of the decoded data does not find that it contains a valid data type, the received signal is decoded using a second decoding technique predetermined to generate a second indication of received signal quality; F) it is determined if the third indication of received signal quality indicates one of a pass / fail condition; G) if a passing condition is indicated, it is declared that the received signal is of a second type of received signal; even more H) if a fault signal is indicated, it is declared that the received signal is not valid.

20. A method according to claim 19, characterized in that the first and second indications of the received signal quality are each a Cyclic Redundancy Verification (CRC) indicator.

21. A method according to claim 19, characterized in that the first type of received signal is a type of control and monitoring message, and wherein the second type of received signal transfers data generated by a user or intended for a user.

22. A method according to claim 19, characterized in that the first type of received signal is a type of Fast Associated Control Channel (FACCH), and wherein the second type of received signal is one of a DATA type or a type of coded voice

23. A method according to claim 19, characterized in that the device is one of a mobile station or a base station.

24. A wireless device, characterized in that it comprises a wireless receiver coupled to a controller having a memory and at least one received signal decoder, for receiving a signal through said receiver and decoding the received signal using a first predetermined decoding technique, for generating and storing a first indication of received signal quality and decoding the received signal using a second predetermined decoding technique, to generate and store a second indication of received signal quality; the controller responds to the received signal quality indications to declare that the received signal is of a first type of received signal or of a second type of received signal, depending on a vapor of the first and second signal quality indications received, and to direct the further processing of the decoded received signal based on whether the received signal is declared as the first type of received signal or the second type of received signal.

25. A wireless device according to claim 24, characterized in that the first and second received signal quality indications are each, an indication of a number of bit errors occurring during the operation of at least one decoder.

26. A wireless device according to claim 24, characterized in that the first type of received signal is comprised of a type of control and monitoring message, and wherein the second type of received signal is comprised of user data that are generated by a user or intended for a user.

27. A wireless device according to claim 24, characterized in that the first type of received signal is comprised of a type of Fast Associated Control Channel (FACCH), and wherein the second type of received signal is comprised of a DATA type.

28. A wireless device according to claim 24, characterized in that the first type of received signal is comprised of a type of Fast Associated Control Channel (FACCH), and wherein the second type of received signal is comprised of a coded voice type. .

29. A wireless device according to claim 24, characterized in that the wireless device is located in one of a fixed part of a wireless telecommunications network or a mobile part of a wireless telecommunications network.

30. A wireless device according to claim 24, characterized in that the first type of received signal is comprised of a type of control and monitoring message, and wherein the second type of received signal is comprised of an Internet data packet.