Allocating speech items to mobile units communicating on a direct mode channel

(72) Inventor (s): Osmo Schroderus Kimmo Kinnunen (74) PlOCurator: Momsen. Leonardos & Cia (57) Abstract: Patent of Invention 'PROCESS AND ALLOCATE VOICE ITEMS TO MOBILE UNITS COMMUNICATING IN A DIRECT MODE CHANNEL AND THEIR MOBILE UNIT'. A process and a mobile unit to allocate voice items to mobile units (RU1. RU2. RU3) moving in a direct mode channel (DM) In the process, a transmission of a first mobile unit (RUI) is emitted during the voice item of that unit moves) in the direct mode channel, a second mobile unit (RU2) takes the turn to speak, and the transmission of the second mobile unit (RJ?) is emitted during the voice item of the second unit moved directly in the channel. In the process, the mobile units (RUI. RU2. RU3j using the channel in direct mode are instructed to operate in such a way that the first mobile unit (RUI) is given priority to start a voice item or request a time to speak after the second mobile unit's voice item has ended (RU2) before the other mobile units (RU3) communicating on the channel directly

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Invention Patent Description Report PROCESS OF ALLOCATING VOICE ITEMS TO MOBILE UNITS COMMUNICATING IN A DIRECT MODE CHANNEL AND THEIR UNIT

MOBILE".

This application is based on patent application FI 955857, filed in Finland on December 5, 1955, the content of which is incorporated herein by reference.

Field of the Invention

The present invention relates to a process of allocating voice items to mobile units communicating on a channel directly. The process comprises the steps of:

transmitting a transmission from a first mobile unit during the voice item of the first voice unit on the channel in a direct way;

a second mobile unit taking over the conversation;

transmit a transmission from the second mobile unit during the voice item of the second mobile unit on the channel in direct mode.

Fundamentals of the Invention

The process of the invention is specifically designed for use in PMR (Private Mobile Radio or Professional Mobile Radio) networks, that is, long distance networks, which ··· if * ·· ti ·· ··· are typically municipal or recfefi J3 ^ networks ..JaiütclrIdade,. · :. ::

• j_and ·· ·· * ··· * · ··. · · * Public where all channels are shared by one or more user organizations. In these networks, subscribers have individual subscriber numbers and also group numbers indicating the communication group or group of subscribers to which the subscriber belongs. Thus, calls destined for subscribers in a specific group can be switched to members of that group.

The invention is suitable for application in mobile communication systems with both digital and analog radio channels. Analog mobile communication systems are described for example in MT 1327, A Signalling Standard for Trunked Private Land Mobi1e Radio Systeme,

January 1968, revised and reissued in November 1991, and MPT 1343, Performance Specification, January 1988, revised and reissued in September 1991, both published by the UK Department of Commerce and Industry, Radiocommunications Agency.

A group call is one of the essential functions of a private mobile radio system. A group call is used, for example, in all types of operations involving more than one participant, particularly when an entire group has to be constantly aware of the progress of events. A group call is a conference call in which all participants can speak in turn and listen to one another. In group calls the entire group is called by a common number. A single radio unit, eg a mobile unit or a radio phone, that is, a subscriber station, can belong to several groups programmed in: ·, * j · _β·· · ·· ··· ·· · radio unit. The schedule can be £ j.xaj peçrpm JtánflDéirt .. ·:.

• Β ·· · Β Bl ·&gt; · * ii *

BBB can be changed by the user of the mobile unit. The system stores information about base stations related to each group number. The group call can cover one, several or all base stations within the service area of ​​the mobile exchange or several mobile exchanges. When a group call is established, a traffic channel is allocated to all base stations related to the group, and each of these base stations transmits a group call message comprising the group number and information about the allocated traffic channel. . If the mobile unit identifies the group number included in the group call message, it will switch the traffic channel indicated in the group call message. Thus, in principle, the mobile unit is always available for a group call if it is located within the predetermined operational area of ​​the group and if it is no longer engaged in another group call.

In addition to the channels in their mobile radio systems, the radio system can employ channels in the direct mode, that is, the operation is in the direct mode. Communicating subscriber stations in direct mode do not communicate directly with the radio network or its base stations. Direct mode channels are FDMA frequencies or TDMA time openings in which radiotelephones or other units can communicate outside the system directly with each other, or via repeater stations either with the system base stations or with other mobile units.

Direct mode channels are typically used in situations where, for example, a number of units; · ··· ·· ·· · ···· ·· · ·· handheld communications communicate with another aj.juuncj · · base station not allowing system channels to be used.

Another important utility for direct mode channels is to add capacity when traffic on the system rapidly increases (for example in an incident) in a part of the system's service area, for example in a local part of it.

A direct mode channel is referred to as a simplex channel or simplex connection. A direct mode channel is a channel that is typically not available at all for use by the system. For example, it can be a channel having a channel spacing equal to that of a mobile communications system,. ex. 12.5 kHz or 25 kHz. Of radiotelephones communicating on a channel in direct mode, the transmitter has tuned its transmitter to the channel and transmits voice or data information. The other radiotelephones using direct mode channels have tuned their receivers to the same channel and will hear the broadcast directly.

Direct mode channel operation may employ analog modulation or digital modulation. A radiotelephone transmitting on a channel can also emit signaling information, such as information about user rights priorities or information about the communicating group on the channel, or data traffic. A direct mode channel can employ encryption or transmit in a clear (unencrypted) voice.

In typical group call traffic for MR systems, there is a need to provide a · ** * · **! · * '··· ·· free space characteristics normjd, íuíflJC Γνάζ: usually two parties are in communication and the others just want to listen. It would be desirable that these two subscribers who participated in the communication are likely to end their dialogue before a third party can interrupt the communication with their voice item. In the prior art approaches, no solution to the above problem was found for the operation of mobile units communicating on a channel in direct mode.

• ·· • ca aaa • aaa aaa aa problem with prior art solutions lies in the absence of any direct mode channel system that would establish the priority of starting voice items from mobile units participating in a group call in such a way that, for example, two subscribers who recently participated in the communication would be given an opportunity to end their dialogue before a third speaker was given a speech.

Brief Description of the Invention

The description below uses the following terms: A recent user is the same as the user who spoke before the user who finished speaking. A user who has finished speaking means a user who abandons his or her turn to speak, that is, ending his or her voice item.

It is an objective of the present invention to solve the problems related to the solutions of the prior art. Thus, the purpose of the invention is to implement recent user priority in a direct mode group call. This means favoring the recent user on a group call on a channel directly.

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This new process for aljoóarf peg4ψφβ, peg&gt; wj ^ · is carried out with the process of the invention, which is characterized by the fact that it additionally comprises the steps of:

issue priority information indicating which or which mobile users are a priority to take the next turn on the direct mode channel of the second mobile unit on the direct mode channel;

in response to the priority information, take the next speaking turn for the indicated mobile unit to be prioritized, transmit the transmission from the mobile unit during the next speaking turn.

A second embodiment of the invention relates to a process for allocating voice items to the communicating mobile units on a channel directly, the process comprising the steps of:

transmitting a transmission from a first mobile unit during the voice item of the first mobile unit on the channel in a direct way;

a second mobile unit taking the turn to speak;

transmit a transmission from the second mobile unit during the voice item of the second mobile unit on the channel in direct mode.

This process according to the second embodiment of the invention is characterized by the fact that it additionally comprises the steps of:

issue priority information indicating which user or mobile users is / are priority to take the next turn on the H '£ re3 mode channel: 3^and* $ Úçl $ '' ;·· · ·· · ··· ·· • ··· mobile unit on the channel in direct mode;

in response to the priority information, taking the next turn to speak for the indicated mobile unit to be a priority;

transmit the transmission from the mobile unit during the next turn.

The invention further relates to a mobile unit communicating on a channel directly, which comprises memory devices, a transceiver and a control unit for controlling the operation of the mobile unit.

The mobile unit of the invention is characterized by the fact that it comprises controller devices to control the mobile unit to operate in such a way that after the termination of the voice item of the second mobile unit, it has priority to initiate a voice item or request a time to speak before the other mobile units communicate on the channel directly.

The invention is based on the idea of ​​recent user priority in such a way that this speaker or user gets a new time to speak faster than any other communicating mobile unit on the channel in a direct way. The aim is for the speaker who precedes the user who has finished speaking to get a speech once, if he so wishes, immediately after the voice item of the outgoing speaker ends, so that no other speaker / mobile unit gets a turn. speak before a recent user of this type.

The basis of the invention lies in ijdéòj ídp:

·· priority of the user who precedes the user who has finished speaking (to obtain the next speaking time) is increased in such a way that the speaking time is granted to the user more easily than to third parties. Recent user priority can also be implemented in addition to several voice items in such a way that the process favors not only the previous user but also the one who preceded it.

The idea of ​​the invention is that the second mobile unit that received the turn to speak after the voice item of the first mobile unit and that ends its voice item, that is, it is leaving its turn to speak, add to the transmission information the the fact that the user who preceded the user who finished speaking, that is, the first mobile unit, has priority to receive the next turn. In response to this information, the first mobile unit can, if it so desires, take the next turn to speak without the other mobile units (third parties) on the channel in a direct way that wish to speak to disturb them by transmitting their voice items. It is obvious that the priority for the recent user can be given either in the immediately preceding unit, that is, first, mobile unit or for several recent users.

It is an advantage of the process and radius unit of the invention that they eliminate problems with solutions of the previously known technique, that is, they enable the user who precedes the user who has finished speaking to be favored when the next voice item is assigned on a channel in direct mode.

Short Description of the Drawings

The invention will be explained fent mãibtí aAetia {He_The4 '\ follow with reference to the attached drawings, in which:

Figure 1 is a schematic view of a situation where subscribers participate in a group call on a direct mode channel;

Figure 2 shows the communication of radius units according to the invention in a direct mode channel;

Figures 3a and 3b are flowcharts illustrating the operation of a mobile unit seeking its transmission turn;

Figures 4a and 4b are flowcharts illustrating the process according to the invention;

Figure 5 is a block diagram of a mobile unit according to the invention, communicating directly on a channel.

Detailed Description of the Invention

Figure 1 is a schematic view of a situation where subscribers participate in a group call. The subscribers SI, S2, S3, using their mobile units with which the present invention relates, belong to the call of the same group Gl; the other subscribers participating in this group call are not known. The group call is conducted on a direct DM channel. SI and S2 subscribers participate in the group call by talking in shifts, thus establishing a dialogue. According to the invention, both SI and S2 speaking subscribers basically allocate times to speak to each other in such a way that the dialogue conducted by these two subscribers can be completed. The S3 subscriber would like to have a time to speak, but according to the invention sometimes to speak SaO • 0 «0 00 00 00« 00 0 000 the S1 and S2 subscribers only. Thus, subscriber S3 is prevented from obtaining one time to speak until the dialogue between subscribers S1 and S2 is completed and the previous subscriber has finished his turn to fail. The arrow 10 in the figure designates the exchange of voice items between subscribers Sl and S2, according to the invention the subscriber who ended Sl inserts in the transmission of his voice item information about the fact that the user S2 that preceded the user who finished Sl has priority to have the next voice item. In response to this information, the previous subscriber S2 may, if he so wishes, take the next turn to speak without the other S3 (third party) mobile units on the channel directly wishing to speak upset him by transmitting his requests from time to time to speak or voice items.

Figure 2 illustrates the communication of radio units RUI, RU2, RU3 according to the invention in a DM direct mode channel. Radio units can be mobile units or any other entities equipped with a radio device that is capable of communicating on a channel in the direct mode. Radio units can also be repeater stations for mobile communication systems. The invention operates in principle as described in conjunction with figure 1.

process of the invention can be implemented for example in the following ways:

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1) The counter of the mobile unit increases the progressive direction in each case after a new voice item; this will be explained in relation to figure 3; and

2) Explicit address through which the subscriber who has expressly ended Ktdícrflct Ãss &amp; Tfasãtef * * * 999 β 99999 999

99 99 999 99

9999 or subscribers who are / are entitled to take the next turn to speak directly on the channel; this will be explained in conjunction with figure 4.

Figures 3a and 3b show flowcharts of the process of the invention. Here, a recent user priority counter built into the handset is used. Hereby the mobile unit keeps a record of how many times to speak were taken after the mobile unit had once to speak. This process works in such a way that the mobile unit ending its voice item adds to its transmission information about how much recent users are favored when the next voice item is allocated.

In this embodiment of the invention, that is, the counter alternative, the procedure is such that whenever a mobile unit abandons once to speak, that is, it stops talking and possibly stops pressing the PTT button (press to speak), it resets your priority counter (cfm. figure 5) to its initial value, eg 1. The counter value is increased whenever another mobile unit takes the time to speak and starts speaking. It is also possible to increase the counter in response to a message informing the mobile unit that another mobile unit has abandoned its turn to speak. That is, when the mobile unit finishes its voice item, that is, it leaves its turn to speak, informs the other mobile users of this fact in its transmission. The transmission from the mobile unit can also include a command for other mobile units to assume once to speak in such a way that the command only gives a priority to once of *

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It is a given value, for example 1, or 2 if specifically the two previous users must be given the right to speak, that is, they must be favored. Naturally, the abandonment message can include any priority parameter value, depending on how recent or remote the preceding mobile unit should be favored.

Through the process, the mobile unit of the user who has finished speaking indicates to the other mobile units how many recent users are favored. Typically only a recent user / mobile unit is favored. The process, however, also makes it possible to favor several preceding mobile units. It should be noted that the information included in the broadcast of the user that ended about how many recent users are favored can also be a channel-specific parameter directly.

When a recent user wishes to speak after the voice item is finished, this must be reported to the mobile unit even before the voice item of the user who has finished speaking has finished. One way to indicate this is to press a PTT button (push to talk) on the handset whose user wants to take the next turn.

A mobile unit seeking its transmission turn stores information on how many times to speak were taken after the last transmission was made as a voice item for the group call in question. If this mobile unit specifically transmitted the previous voice item, the recent user counter parameter of said mobile unit is 1.

The transmission location is calculated * ã'dcütit £ il £ ãaH3d \ I »» · «··.« I • · »·. ·· ··· ·· • ··· the starting point of the random access frame and the counter of the recent user of the mobile unit that tried to transmit.

The mobile unit can initiate transmission if any preceding transmission positions have not been used. This is determined by the handset receiving a confirmation message from the handset that has finished speaking. If there is no confirmation from the handset that has finished speaking or if the confirmation is negative, the handset starts issuing a request for one time to speak in the normal way (first attempt).

The flowcharts shown in figures 3a and 3b illustrate the operation 301 of a mobile unit RU seeking its transmission turn. The mobile unit receives in 302 communications on a channel in the direct mode. Simultaneously, the UK mobile unit supervises in 303 whether the voice item of the recent user / subscriber is ending. If the voice item does not end, the operation of the mobile unit will revert to the previous step 302, in which the mobile unit is receiving communication. If, on the other hand, the voice item ends, the UK mobile unit tests in 305 whether its user has requested their turn to speak. If this is not the case 306, the UK mobile unit waits at 307 for the user's voice item or start of communication. In the next step 310, it is examined whether the user has requested a time to speak, and if so, 315, the execution of the process moves to step 316, in which it is tested whether the priority of the recent user is invoked or activated. If, on the other hand, it was verified in step 310 that the user did not request 311 times to speak, in the next step 312 it is tested whether the communication starts. Otherwise, the execution of the process returns in '$ l'S', S * ':

e «e · eevie ee · eeee · e • ···· eee ee · ee * ··· in which the user voice item or start of communication is awaited. If, on the other hand, communication starts, the recent user counter is incremented by one step.

If in step 310 the user requested 315 times to speak, the process proceeds to step 316 in which it is examined whether the priority of the recent user according to the invention is invoked or activated. If not, the process proceeds to step 317, in which the first start position is established to be the same as the transmission position of the first request for once to speak, added to the number of recent users. This first starting position can also be set to be higher than the one above, that is, higher than the transmission position of the first request for once speaking plus the number of recent users. Subsequently, step 318 takes over the process for the normal first attempt procedure.

If, on the other hand, it was found in step 316 that the recent user priority according to the invention is invoked or activated in 319, the process proceeds to step 320. This step examines whether the number of recent users is higher that or equal to the recent user counter value.

Otherwise, the execution of the process proceeds to step 317, from which the process passes on to step 318 for the first attempt procedure. If, on the other hand, the number of recent users is 322 higher than the value of the recent user counter in step 320, the transmission position of the request for once speaking is established in step 323 to be the transmission position of the first ··· · ·· ·· ·· ··· ··, · request to speak once summed up: cpm-5cç^and,yãll3r ·. to. :

S ”2 1« «a ·· ··· ·· · ·» »aaa recent user counter. Subsequently, in step 325 the next transmission position is awaited. After that, the position of the transmission of the request for once to speak is examined in step 326. If the position is not correct in 327, the process proceeds to step 324, in which it is examined whether the communication starts. If, on the other hand, the transmit position is correct, a request at a time to speak is issued in step 330 using the reserved transmit position, after which it is examined in step 331 if a positive confirmation from the mobile unit that ended RU was received. If this is not the case in 332, the execution of the process proceeds to step 317, in which the starting position of the first attempt is established. If, on the other hand, the confirmation received from the mobile unit that ended RU is positive, the process proceeds to step 333, in which the mobile unit is transmitting its transmission. Subsequently, the process proceeds to step 334, in which it is tested whether a voice item termination request is received from the user. If there is no request to terminate the voice item, 335, from the user, the execution of the process returns to step 333, in which the communication is transmitted. If, on the other hand, a voice item termination request is received from the user, the execution of the process is continued from step 336 in which the mobile unit abandoning the turn to speak issues to the other communicating voice units on the mode channel direct priority information with which the other mobile units are informed that they can try to take the next turn if their recent user counter has • flfl flfl flfl the value 1. This value is typical of favoztederf &amp; «Msu ^ rio^aaq {ieI; ·· «·« ·· ·· ··· ·· · had his turn to speak immediately before the subscriber who ended. It is of course also possible to set the priority parameter to some other value, which would mean that another recent user or more than one of the recent users is favored.

Figures 4a and 4b are flowcharts illustrating a process according to another embodiment of the invention, using explicit addressing when a user who has finished assigns voice items to the mobile units that are about to have a turn to speak next.

In this embodiment, the procedure is of such a nature that when a mobile unit receives from its user an indication of the fact that the user wants to take the next turn, the mobile unit stores the recent user's identification (mobile unit). When the user then finishes his voice item, the mobile unit transmits an indication to the recent user in its transmission. In response to this indication, the recent user can take the time to speak if they wish.

In this process, the user finishing his voice item, that is, the user who finished, that is, the mobile unit RU, unequivocally indicates the address of the user or recent users.

When the recent user wants to speak after the voice item, this must be reported to the UK mobile unit before the voice item is finished. In figure 4, this indication is shown in step 408, in which it is tested whether the user has requested a time to speak. If the recent user wishes ·· ·· ·· ·· ····. · To have a time to speak, he can signal: cB áetídefeehò * jã »·. ·, · ·: ··: ·· .... ........

999 example by pressing its PTT button (press to talk).

If the address of the mobile unit RU is the same as that defined as the address of the previous mobile unit RU (recent user) in the transmission of the voice item of the mobile unit that ended RU, the mobile unit RU can avail itself of the possibility by a request by your turn to speak reserved for the previous mobile unit.

The transmit position is counted using the start position of the first random access frame.

If there is no confirmation of the mobile unit that ended RU or if the confirmation is negative, the mobile unit RU initiates the request for once to speak in the normal manner according to the first attempt procedure explained above.

In the flowcharts of figures 4a and 4b, steps 401-415 correspond to steps 301-319 shown in figures 3a and 3b. The process proceeds to step 416 shown in figures 4a and 4b if it has determined in step 412 that the recent user priority explained above is invoked or activated on the mobile unit that spoke during the previous speaking turn. In this case, it is examined in step 416 whether the address of the recent user is the same as the address of the mobile unit itself. If this is not the case, the execution of the process proceeds from 417 to step 413, which was explained as step 317 in the flowchart of figure 3a. If, on the other hand, the address of the recent user is the same as the address of the mobile unit itself, the execution of the process proceeds to step 418, in which the mobile unit issues a · ···_β·· _β· »······ S ·· request once to speak to 4,_Thetiniáae £ e: «&lt;gQvef“ quiS · ended that sent a message indicating the end of its transmission. As a next step, the mobile unit that wishes to speak in turn supervises in step 419 whether a positive confirmation for a turn to speak request made by the mobile unit that wishes to speak is received from the mobile unit that has ended. If the confirmation is negative at 420 or if no confirmation is received, the execution of the process proceeds to step 413 explained above and from there in addition to the first attempt procedure. If, on the other hand, the confirmation received from the mobile unit that ended is positive, the execution of the process proceeds to step 421, in which the mobile unit stores the address of the user who spoke previous (which ended) and begins to transmit, this yes, take the time to speak. As long as the user of that mobile unit does not provide in 423 a request to terminate the voice item, that is, release of the PTT button, the mobile unit transmits its transmission, that is, it keeps its turn to speak.

When a voice item termination request is received from the user of the mobile unit, that is, when the user releases the PTT button, the mobile unit emits 424 to the other mobile units communicating in the channel directly with priority information adding the address of the recent user to your broadcast. whether the recent user priority is invoked or enabled.

By the operation according to another embodiment of the invention, the procedure is of such a nature that the priority information is information identifying the voice item indicating the identifier of one or more items of ··· ·· ·· ·· * ·_β ··· _β··_β_β··_β previous voice whose users have priorjj $ Ldq to ^ têr: srwéfe: «·· to speak next. Here the voice item identifying information is compared with the mobile units that received the priority information with the information stored in the mobile unit about the identifiers of the voice items that the mobile unit owned. If said comparison shows that the mobile unit has priority to take the next turn and the user of the mobile has indicated his desire to take the next turn, the mobile takes the next turn, unless another unit indicated mobile having priority previously reserved the turn to speak next.

Figure 5 is a block diagram of a mobile unit 500, i.e., a radiotelephone used by a subscriber, a mobile unit, or a subscriber station, communicating on a channel in the direct mode. The task of the transceiver (TX / RX) 501 is to tune the radio channel used in each case. The transceiver 501 incorporates an antenna 502 connected with an RP radio channel. Normally, radio frequencies between 60 MHz and 1000 MHz are used (VHF and UHF bands), although other frequencies can also be used. Analog modulation can be used on the RP radio channel, the modulation modality being normally phase modulation. Other modulation modes can also be used. A voice frequency subcarrier (FFSK), for example, can be employed for signaling transmission. 0 Radio channel can also be conducted digitally. The mobile unit can adapt and communicate on the reverse and emission frequencies of the channel directly.

<img file="BR9605840A_D0003.tif" />

·· · · · · · · ·· electroacoustic transducer devices, typically a 506 headset and a 507 microphone, and possibly keys pertaining to call initiation and termination and selection. Since in a long distance system and especially in direct channel communication and an RP radio channel is advantageously simplex, the handset usually also has a push to talk (PTT) button, which has to be pressed during the time. of voice. 0 push button to speak is not shown in fig. 7.

The task of the 503 control unit is to control the operation of the mobile unit. The control unit 503 has access to user interface 505 from which it obtains impulses for the initiation and termination of a call, for example. The control unit 503 can also provide the user with audio or visual signals related to the operation of the mobile radio and / or radio telephone system via the 505 user interface.

The control unit 503 is connected with the TX / RX 501 transceiver. The channel used by the transceiver is determined by the control unit 503, which means that the transceiver 501 tunes to the channel, that is, radio frequency, determined by the control unit. 503 and with an appropriate opening time. The mobile unit of the invention is capable of tuning a channel in the direct mode and the reverse and emitting channels (frequencies) of the system channels and also with a desired opening time in the channel. The transceiver 501 is also activated under the control of the control unit 503. The control unit 503 receives and sends

• ... · ···· ·· · signaling via transceiver 501. UijãJurji 3 · • ·· * according to the invention, communicating in a direct mode channel, can for example be used in a communication system radio comprising a radio network with at least one base station and subscriber stations and possibly one or more repeater stations / networks transmitting communication between at least one base station and communicating subscriber stations on the direct mode channel.

The mobile unit communicating on a channel in a direct manner comprises memory devices 510, a transceiver 501 and a control unit 503 to control the operation of the mobile unit.

A mobile unit RUI, RU2; 500 (figure 5) according to the invention comprises: controller devices 516 for controlling the RUI mobile unit to operate in such a way that it receives priority to initiate a voice item or to request its turn to speak after termination of the voice item of a second mobile unit RU2 before the other mobile units RU3 communicating in the channel directly.

The mobile unit according to the invention is characterized by the fact that the controller 516 to control the mobile unit RUI to operate is adapted to give the first mobile unit RUI priority to start a voice item or request its turn to speak immediately after the termination of the voice item of the second mobile unit RU2 within a predetermined period of time.

The RUI mobile unit; 500 (figure 5) of the invention additionally comprises: adding devices 517 for adding information to the transmission of the RUI mobile unit, »··· ·· · ·· ···· ·· when the RUI mobile unit leaves its cfe â |} af »Pr &amp; vj.?„ The information indicating that the RUI mobile unit wishes to have priority to start a voice item or to request its turn to speak immediately after the termination of the voice item of the second RU2 mobile unit which took the next turn.

The mobile unit of the invention additionally comprises transmitting devices 511 for outputting priority information indicating which or which mobile units have priority to request the next turn to speak on the right channel.

The mobile unit of the invention additionally comprises a priority counter 512. The value indicated by the counter indicates the number of times to speak taken by the other mobile units after the voice item of said mobile unit.

In the mobile unit of the invention, the transmitting devices are adapted to insert the priority parameter value in the priority information, indicating how many recent users are favored.

The mobile unit of the invention additionally comprises comparator devices 513 to compare at 320 the value of the priority parameter included in the priority information received by the mobile unit with the value stored in the priority counter of the mobile unit 512, and in response to said comparison, if the comparison shows that the mobile unit has priority to take the next turn, directing the unit to take the next turn, unless another mobile unit indicated to be a priority has previously reserved the turn to speak next.

ζ ··_β ·· ·· · ·· ··· ·

Otherwise, the devices g.prapsnríqsçfe ^ õlL * 9 99 99 99 999 99 in the mobile unit are adapted to insert in the priority information the identifier of the mobile unit that had the previous turn, in response to which the previous mobile unit takes the time to speak next.

The mobile unit of the invention additionally comprises voice item initiator devices 514 responsive to the i dent ifi cator of the first mobile unit1 included in the priority information issued by the second mobile unit RU2, so that the mobile unit takes the time to speak Following.

9999 9 9

The mobile unit of the invention is further characterized by the fact that the transmitting devices 511 are adapted to include in the priority information voice item identifying information indicating the identifier or identifiers of the preceding voice items whose subscribers have priority to receive the next speaking turn.

The mobile unit of the invention additionally comprises comparator devices 515 for comparing the voice item identifying information included in the priority information received by the mobile unit with the information stored in the mobile unit about the talk times identifiers that the mobile unit had, and in response to said comparison, if the comparison shows that the mobile unit has priority to take the next turn, instruct the mobile unit to take the next turn to speak, unless another mobile unit indicated that it is a priority has previously reserved the next turn.

The drawings and description òertS.neritQ * · ·· ·· ··· ·· · same are only proposed to illustrate the idea of ​​the invention. The process and the mobile unit according to the invention for allocating voice items to the mobile units communicating on a channel in the direct way may vary in their details within the scope of the claims. Although the invention has been explained in the above mainly in the context of PMR mobile units, the invention can also be used in connection with other radiotelephones or other mobile units or mobile phones.

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