CH625653A5 - Method for digital information transmission by radio - Google Patents

Description

The invention relates to a method for digital information transmission for mobile subscriber stations in the large area of a radio network, which consists of several radio concentrators with a mutual spatial arrangement with overlapping radio areas and which has a frequency distribution plan for the radio concentrators that largely co-channel interference in the respective radio area including its overlap area excludes.

A radio network of this type is described, for example, in US Pat. No. 3,310,741.

There is a whole range of radio networks of different structures for mobile public and non-public radio services. In general, a distinction is made between public mobile land radio (ÖbL) and non-public mobile land radio (NöbL). The public mobile land radio comprises the mobile telephone subscribers who can be connected to the dialing exchanges of the public telephone network via radio exchanges. The groups of participants in the non-public mobile land radio include the public security organs such as the police, fire brigade, accident services and civil protection, as well as service groups such as taxi companies, transport companies, industrial radio, business radio, construction companies and the like.

The constantly growing interest in mobile radio and the associated increase in the number of subscribers shows more and more that the system organizations used in known radio networks are not very suitable for large numbers of subscribers. The assignment of the radio subscribers to the different radio concentrators is partly done manually according to geographical criteria, so it does not take into account the optimal accessibility to the location. It also proves to be disadvantageous that the allocation of free channels, at least when the connection from the radio concentrator to the subscriber station is established, is carried out by the radio concentrator, that is, it takes little account of the radio situation of the subscriber station with regard to co-channel and adjacent-channel interference. Another shortcoming can be seen in the fact that the likelihood of blocking by the organization increases very quickly if there are large accumulations of registrations and connection requests during rush hours, even if free transmission channels are still available.

Another lack of the usual in known radio networks

3rd

5

10th

15

20th

25th

30th

35

40

45

50

55

60

65

625 653. 4th

It can be seen in system organizations that, on the other hand, the period of time which extends from the time of the reception, station, which is connected to a connection, during a call or from the occurrence of a connection request of the message transmission is extended on the part of the Subscriber station passes until the loan loses the network organization. desired connection is established. Is the structure of the i (.

It is the object of the invention to provide 5 organizational channels for radio networks of such a type that between the type described in the introduction, a given time interval suitable for large numbers of subscribers and a possible call is suitable for the traffic flow, which is appropriate that in these time intervals the “that which in known system organizations of radio networks subscriber station eliminates the defects that the radio concentrator reports as freely reported. operating channels as a precautionary measure

This task is checked for a method for digital information and see a usability as a suitable mation transmission for mobile subscriber stations in the recognized free operating channels in a further memory large area of a radio network according to the invention after which also constantly kept up to date 'Characteristic of patent claim 1. In this case, a call is made to the subscriber station

The invention is based on the knowledge that by means of or if the subscriber station wishes to establish a connection, central organization channels which are not required for the traffic concentrator to immediately provide the radio concentrator with one or more information free operational channels for establishing the desired exchange within a radio network can only be made considerably easier, but rather suggest a commitment.

in addition, even with large numbers of participants a faster In this context, it is advantageous if the partial radio-organizational traffic flow is made possible. The operator station requests the operating channel requested by her for the connection via the organisa- tion through the information channel transmitted to them, informs the radio concentrator and the radio accounts via the ones offered by the radio concentrators free centrator, in turn, this requirement through feedback channels that confirms the desired operating channel based on their own radio technology situation.

select the most suitable operating channels. To keep between the subscriber stations and the

The situation is particularly favorable, if the 25 radio concentrators take place via the organizational channels-information exchange between the radio concentrators and the information exchange is simple and time-efficient - it is sensible to carry out the subscriber stations in the operating channels and the organ, that for the information nization channels in duplex mode. the various organizational functions, such as identification,

The subscriber stations expediently check the quality of registration, reregistration, attendance check, occupancy and the radio accessibility of the various radio calls, each radio concentrator has a summation channel concentrators, taking into account the neighbors and who has this information available in a time

Summarizes co-channel interference based on the field strength and / or the tiplex frame. Here, the beginning of the frame phase jitter of the received organizational channels, since the total organization channel is marked by the information block practically the entire radio organizational information. In addition, the sum organization channel exchanges between the subscriber stations and radio concentration 35 for the presence check of one over two and gates takes place via the organization channels anyway. more frames extending in length to the temporal

Furthermore, it is advantageous if the superframe channels that can be adjusted in the fluctuating traffic load from the radio concentrators to the subscriber station use. The superframe takes into account the fact that a periodically transmitted information block is sufficient, in addition to the fact that it is generally sufficient if the presence radio area identifier contains information about the traffic check of the participants in relation to the frame level of the radio concentrators, that is to say this information period of the sum organization channel much slower mations continuously takes place in the rhythm of the frame period of the cycle. In addition, the number of subscriber organization channels is available to the subscriber stations. Stations that can be registered with a radio concentrator are the maximum. that can, much larger than that of the radio concentrator

In order to ensure the smoothest possible operation, it is important to provide 45 operating channels, so that the radio concentrators constantly check their operating channels for the larger number of registration-related operating characteristics, and only essential for their subscriber stations in an extra frame bes-

have such free operating channels accommodated in the relevant organizer.

transmission channels to the subscriber stations, whose In a radio network with a large number of channels and large Mel-

Radio-technical properties for the implementation of such a decapacity, it makes sense to be of sufficient quality depending on the local traffic transmission. a radio concentrator has two or more total

In a preferred embodiment of the method, organization channels with the same time-division multiplex frame according to the invention cease to be available in a radio area. In this case, the subscriber station registering organizational channels that are responsible for the sum of the radio concentrators differ from one another only by a traffic-related connection to this process, which concentrates in the responsible organizational channel on the radio 55-load-related different priority and continuously stores the free operating channels registering with the radio concentrator and stores them in one slave stations from each other.

Memory that is kept up to date. In a further development of the invention, if the radio network only checks when a connection request occurs, a radio frequency band is available which shows a small subscriber station the operating bandwidth that was last reported as free, to a decentralized operating channel and shows its radio usability The assignment is dispensed with in that the most suitable radio frequency operating channel is the radio concentrator for the zen of the organization channels for the middle area of the

Establishing the desired connection. Radio frequency band of the radio network can be set and

If the radio concentrator avoids checking that the assignment of free operating channels to the subscriber states, operating channels by the subscriber station only after a request has been made centrally by the radio concentrators, the time will be done. It is assumed here that the radio quality of the Organidas available to the subscriber station for listening to subscriber stations, which is checked by the sub-room, is optimized, but that the channels are also available to the only relatively low frequency

.uence distance from the associated company channels, • at least in a first approximation,. The differences in reception that actually exist can be easily compensated for by using the room diversity technology on the reception side of the subscriber stations.

Instead of a time-division multiplex organization channel with an overframe for the presence check, the radio concentrators can each have two or more organization channels, to which the various organization functions are assigned in a suitable manner. In this context, it is expedient to provide, at least for the presence test, a separate organizational channel (reporting channel) which provides a time slot for each registered subscriber station. The frame period of this reporting channel is n times (for n a whole positive number) the frame period of the other organizational channel or channels.

It is expedient to adapt the reporting channel in its frame period discontinuously in the time period corresponding to the frame period of the further organization channel or the further organization channels to the fluctuating number of registered subscriber stations.

In a first preferred procedure, the frame period of the reporting channel can be shortened with a decreasing number of subscriber stations registered by regrouping the subscriber stations registered in time slots with a high number of orders into unoccupied time slots with a low number of orders.

In a second preferred procedure, the adaptation of the frame period of the reporting channel depending on the number of registered subscriber stations is brought about automatically in that the subscriber stations registered in the radio area are periodically called up by the responsible radio concentrator via the reporting channel with a period dependent on the number of registered subscriber stations for submitting presence reports will. Accordingly, if many subscriber stations are registered with the radio concentrator, a cycle for the presence check results in a longer period than in the case in which only a few subscriber stations are registered with the radio concentrator.

As practice shows, it is not appropriate to require a subscriber station registered via a radio concentrator to automatically log off from the radio concentrator when deactivated. For this reason, it makes sense that the presence of a subscriber station deregistered in a radio area from the responsible radio concentrator is automatically deleted in the memory of the radio concentrator if the subscriber station does not send a presence message to the radio concentrator within a time interval of a predetermined length via the responsible organizational channel.

In a further development of the method according to the invention, a predetermined number of discrete time slots are available for the registration and calling of subscriber stations with a radio concentrator within a frame period of the responsible organizational channel, which are occupied by each of the subscriber stations if necessary according to a pseudo-random law. In this way it is possible with simple means to avoid a mutual blocking of subscriber stations when a number of logon and call processes occur.

In this context, it is advantageous if each subscriber station has a frame-synchronized and bit-clock-synchronized scrambler, which selects one of the time slots of the responsible organizational channel for occupancy on request.

The method according to the invention is extraordinary

625 653

advantageously the possibility of maintaining the functionality of a subscriber station in relation to the network organization even when this subscriber station is occupied with a connection. In this case, it makes sense for the subscriber station assigned to a connection to interrupt transmission in the time intervals in which the information blocks appear in the organization channels and to alternately check the radio channel-specific operating channel assigned to the connection for the continuation of the connection and to listen to one of the organization channels outside the radio range .

The periodic checking of the operating channel occupied with the connection is expediently carried out by a mutual exchange of messages between the subscriber station and the radio concentrator. If these messages fail to appear over several test periods, the connection is triggered.

The disturbances which the continuous flow of messages experiences due to the periodic interruptions of the occupied connection when listening to the information blocks of the organizational channels by the subscriber station can be eliminated in a simple manner by increasing the transmission speed on the radio link, in connection with a transmission and reception side Intermediate storage of the message signals at the subscriber station and the radio concentrator.

Since in a further training a subscriber station can constantly check its radio-technical situation by listening to the organizational channels of the different radio areas, even when it is occupied with a connection, it is able to make a decision about when a radio area change is necessary even when it is busy. This includes the subscriber station intending to change the radio area first of all from the channel information of the new radio area recognized as suitable in terms of technology and then registers with the associated radio concentrator, specifying the free operating channel recognized as suitable. The new radio concentrator acknowledges the message with a response prompting the subscriber station to wait, in which the subscriber station maintains the original connection via the previous radio concentrator. After preparation of the transfer of the existing connection in the dialogue between the previous and the new radio concentrator, the new radio concentrator informs the subscriber station of the time for the final switchover, in which the new radio concentrator and the subscriber station simultaneously carry out the final switchover.

To ensure the functionality of this operational process, it makes sense to repeatedly transmit the time for the final switch from the new radio concentrator to the subscriber station in such a way that the remaining time difference is still recognizable for the subscriber station and that the subscriber station can receive one of these if it is received correctly Notifications prompted the switchover at the specified time.

The method according to the invention requires a relatively high degree of technical intelligence on the part of the subscriber stations, the effort of which should be kept as small as possible. This can be achieved in an extraordinarily advantageous manner in that the sequence of the radio-organic functions on the part of a subscriber station is controlled by a microprocessor.

The invention will be explained in more detail below with reference to exemplary embodiments shown in the drawing. Mean in the drawing

1 is a schematic representation of a radio network constructed in the manner of a cellular system,

5

5

10th

15

20th

25th

30th

35

40

45

50

55

60

65

625 653

2 shows an overview of the distribution of the channel frequencies within a frequency assignment area consisting of seven radio areas,

3 shows the schematic representation of a first radio-organizational process between a subscriber station and a radio concentrator according to the invention,

4 shows a second radio-organizational process between a subscriber station and a radio concentrator according to the invention,

5 shows a third radio-organizational process between a subscriber station and a radio concentrator according to the invention,

6 shows a fourth radio-organizational process between a subscriber station and a radio concentrator according to the invention,

7 shows a fifth radio-organizational process between a subscriber station and a radio concentrator according to the invention,

8 shows a sixth radio organizational sequence between a subscriber station and a radio concentrator according to the invention,

9 shows an organizational multi-channel structure according to the invention,

10 shows the block diagram of a radio concentrator operating according to the method according to the invention,

11 shows the block diagram of a subscriber station operating according to the method according to the invention.

In the basic diagram of an expandable mobile radio network shown in FIG. 1, in which the radio concentrators are arranged spatially in the manner of a cellular system, the radio concentrators each implement a radio range with an average radius r. For example, the average radius r is about 15 km. Such a cellular radio network is given, for example, in the “Yearbook of Electrical Telecommunications”, year 21, 1970, publisher for science and life, Georg Heidecker, Bad Windsheim, pages 305 to 311, in particular page 308, picture 1. The radio network expediently works with frequency duplex in the UHF range at approximately 450 MHz. The transmission and reception bands have a frequency spacing of ^ 10 MHz that is necessary for 100% electromagnetic compatibility.

As can be seen in more detail in FIG. 1, the radio network is subdivided into frequency assignment areas, each of which has seven radio concentrators with the numbers 1 to 7. In Fig. 1 three differently hatched frequency assignment areas are highlighted, their radio concentrators with F1 ... F7,

F '1 ... F' 7 and F "1 ... F" 7 are designated. In contrast to the other radio concentrators marked with a dot, the radio concentrators Fl, Fl 'and F "1 are represented by a cross. This is to indicate that these radio concentrators form radio switching centers for the connection between the different radio areas and to the switching centers of the public telephone network are expanded.

The frequency assignment areas with their seven radio concentrators are all constructed in the same way and have the same frequency distribution plan. The numbers 1 to 7 of the radio concentrators also designate the radio area numbers.

To ensure that the mobile subscriber stations T, one of which is shown in the radio area F1, can be reached without gaps, the radio areas of the radio concentrators have a mutual overlap. No co-channel interference should occur in the overlap area, if possible. Co-channel interference from more distant radio concentrators is possible taking into account a minimum channel-to-noise ratio depending on the type of demodulation at the receiving location of a mobile subscriber station. The frequency distribution plan takes this fact into account within a frequency allocation range, taking into account the higher-level spatial planning scheme of the adjacent frequency allocation ranges.

The frequency assignment to the individual radio concentrators is carried out in such a way that the radio concentrators which have the same area numbers and which work here with the same radio frequencies have a sufficiently large mutual minimum distance. In the illustrated embodiment, it is approximately 80 km.

A frequency distribution plan which is favorable for the cellular system according to FIG. 1 and which repeats itself in each frequency assignment range is specified in more detail in the diagram of FIG. 2. Thereafter, the transmit and receive bands X and Y for full duplex operation each comprise 120 channel groups KG with seven individual channels each. The number of radio channels per frequency assignment area is thus 840. Each of the radio areas 1 to 7 is assigned a channel per channel group, in such a way that the position of the channels assigned to a specific radio area remains the same within the channel groups. In Fig. 2 are above the transmit or. Receiving band XY the channel group numbers KG, the channel numbers KNr, the radio area numbers FNr and the radio areas 1 to 7 belonging to a frequency assignment area are plotted in successive lines. 2, the first channel of a channel group KG is assigned to radio area 1, the second channel to radio area 6, the third to radio area 4, etc. With this arrangement it is achieved that the radio channels used in each radio area always have a mutual frequency spacing of own six channels. The channels of each radio area are so far apart that neighboring channel interference from area-specific transmitters can be avoided with certainty. With the frequency assignment shown in FIG. 2 in a frequency assignment area, it is further achieved that the radio areas in the immediate vicinity of a frequency assignment area operate with the maximum possible frequency spacings. As traffic estimates show, a radio concentrator designed for 120 channels has a capacity of max. 2400 subscriber stations, for which such a radio concentrator must also be designed.

The radio-organizational tasks in such a radio network operating with digital signal transmission, for example binary frequency modulation in full duplex operation, are carried out according to the method according to the invention with the aid of organizational channels within the radio area, which are listened to by the subscriber stations and with the aid of which the subscriber stations understand themselves from their own radio technology perspective out, taking into account the traffic load of the network, register for a radio area or change the radio area. Furthermore, the other radio organizational tasks such as attendance check, occupancy and call are carried out via these organizational channels.

There are basically different options for the structure of the organizational channels. On the one hand, different radio organizational functions can be divided into two or more organizational channels per radio area. This leads to simple and clear circuitry structures on the part of the radio concentrators, but requires that the subscriber stations must always jump back and forth in terms of frequency between two and more organizational channels for the radio-organizational information exchange, which of course also involves an increased expenditure of time.

At least in the case of radio networks, the radio areas of which are designed for small and medium number of channels, it should be more advantageous overall to combine all the organizational functions in one collective organization channel. Such a summary is useful when using digital technology insofar as the various organization

6

5

10th

15

20th

25th

30th

35

40

45

50

55

60

65

7

625653

nization functions easily signaled in a time-division multiplex frame structure. Thereupon the subscriber station signaled to be accommodated in the door. This basic structure of an organisa-transmission path of the organization channel to the radio concentrator F2 tion channel can also be used with large channel numbers per radio in a time slot A, the first notification signal EM-the radio area in such a way that how the concentrator F2 of the radio area 2 acknowledges in the organization - It has already been indicated in the introduction, instead of such a 5 channel OK of the subscriber station in the subsequent time total organization channel, two or more such slot B this initial message by the MF call - In the organization channels in connection with a traffic-related time slot B of the organization channel OK Radio station-dependent pre-authorization scale is provided concentrator F2, the subscriber station T follows this message. call with the MT participant message. This is the registration

The schematically illustrated radio organizational process of the subscriber station in the radio concentrator F2 processes according to FIGS. 3 to 8 is completed by such a total organization. She is now constantly listening to this organizational channel. As shown in FIGS. 3 to 8, this has a frame period x in the event of a call directed to it in one of the sum organization channels OK and time slots B or free channel information in one of the time slots ZS which are of equal width. Total slots A of the organization channel. There are three different types of time slots in this preamble, namely 15 gait is only used in time slots C, in which the time slots C, A and B in the organization. The time slots C always mark the channel of information K transmitted, the beginning of a basic frame at each and contain the information second interrupted incoming frame. This jumps to block K, which, in addition to the radio area identifier, informs the subscriber station of one of the organizational channels on the occupancy of the radio areas 1, 3 to 7 belonging to the radio area and checks them in the permanent radio concentrator. In the time slots F2 of the radio area 2 which follow the time slots 20 change with the information block K of the radio concentrator C and always occur alternately, in which the subscriber station registered A-B and B can transmit different information, respectively, for radio accessibility. Which will wear per radio range. The first letter, possibly with the results of the radio accessibility, followed by the number of the name for the radio are continuously averaged and the mean values are recorded in an organizational procedure according to FIGS. 3 to 8 over time t 25 memory of the subscriber station.

give the activated station, namely the subscriber station T If the subscriber station determines that the radio

or a radio concentrator Fi, while the second socket accessibility within the registered radio range combination of letters and numbers makes the respective organizations considerably worse than the radio-technical accessibility specifies channel or voice channels. In detail, OKi means to another radio area, it initiates a radio area - the organizational channel of the radio concentrator Fi, Fi the radio - 30 changes.

concentrator and GKi the selected voice channel of the radio. The subscriber station then also directs a radio concentrator Fi. Those who continue to appear in the representations of the change of radio area, if the radio concentrator, in which the arrows indicate the organizational processes they show the Rieh- is logged in, informs them in information block K that the device in which something is being transmitted. The transmitted signal is a danger of a blockage due to the time-fluctuating traffic load caused by a letter or a combination of letters when the radio concentration is registered. exists, d. H. the average occupancy rate is a critical value

3 has exceeded in the radio organizational. The subscriber station does this

The process of registering a partial change that is in operation is, however, only if the envisaged slave station is reproduced at a radio concentrator. Radio concentrator in addition to its reach in terms of radio technology.As soon as the subscriber station switches on, it begins to request the 40% availability of a cheaper medium occupancy level up to 7 which justifies the radio area organization channels OKI to OK7 of the seven radio areas 1 change to 7 according to FIG. 1 on its radio technology Suitability to be verified.

The corresponding activities are shown in FIG. 3 in the processes designated T-OK1, Um in the event of temporal accumulations of initial notification signals T-OK2, T-OK3 ... T-OK7. The likelihood of a mutual blocking of checking of the organizational channels has shown that the 45 partial radio area 2 registering for the same radio concentrator for the subscriber station T from its own radio stations is as low as possible, the participant-technical situation is the most favorable Is radio range. mestations equipped with discarding parties. The discarding party jumps at the end of the check interval of the organization dice for the channels of radio area 7 to be issued by the subscriber stations, in turn, on the organization channel initial message signals, quasi-randomly, frame time slots A into the channel of radio area 2 and listens to them. At the beginning of a 50 the subscriber stations then send their first-time signals to the new channel of the organization channel of radio area 2. In the same way, the rejection party comes into action, if the one labeled F2-OK, the subscriber station receives the subscriber stations at the radio concentrators, to which the information block K is added and supplemented in the organization channel, send out call signals or join one that has already been done want to avoid the bit synchronization performed by another radio concentrator.

through frame synchronization. At the same time, it finds out through 55 in FIG. 4 the time sequence of the establishment of a connect information block K is the occupancy state of the radio connection to the subscriber T via the radio concentrator F2 of the centrator. The information about the occupancy status of radio area 2 is shown. First of all, the subscriber receives information about the extent to which the reporting capacity in the organization channel OK of the radio concentrator F2 has been exhausted, the value of the average occupancy of the information block K and continues to listen to the organization channel channels and whether all speech channels of this radio concentrator are at the moment to which he is registered. channels are occupied or not. If the reporting capacity is exhausted two timeslots later, he receives one in timeslot A and / or if the average occupancy has a critical value. The radio concentrator has exceeded the offers he has made, the subscriber station must use what he sees as the free operating channels. This information in terms of radio technology by listening to the responsible organization is marked with V. The information V is transmitted in the next best radio concentration slot A ascertained in each time station channel in the organization channel, but it is changed over to gate. In the exemplary embodiment according to FIG. 3, and for the sake of clarity, it is assumed in FIG. 4 and the further FIGS. 5 to 8 that the information block K of the organization bar is only given where it explains the OK of the radio area in each case 2 A still free registration capacity is necessary for the functional sequence.

625653

8th

In the next time slot B, the subscriber station receives a call directed to it via the organization channel OK of the radio concentrator F2, which call is designated RF. The subscriber station always saves the latest status of the free operating channels constantly communicated to the subscriber station in the rhythm of the frame period in the organization channel, so that when a call is received, it can then immediately perform a free search FS from the collective of the free channels communicated by the radio concentrator. For this purpose, it leaves the organizational channel of the radio concentrator F2. After completion of the free search, the subscriber station reports to the radio concentrator in the organization channel in a time slot B which, from its own radio technology point of view, the most suitable free operating channel and at the same time acknowledges the received call. The radio concentrator acknowledges this message with the signal QF already in the proposed voice channel GK of the subscriber station which has meanwhile switched over to this voice channel. The connection is thus established and the message transmission between the subscriber station and the remote subscriber station which initiated the call can be carried out via the radio concentrator F2. This is illustrated in FIG. 4 by the double arrows in connection with the cross-hatched sections of the speech channels for both directions.

Even when the station is busy, the subscriber station must check the radio accessibility of all radio concentrators in order to be sure that the connection is still established and, on the other hand, if the radio accessibility deteriorates significantly, to be able to decide which radio area to switch to . This check is again carried out exclusively in the rhythm of the frame period t in the time slots C specified in the organization channel. In the first time slot C after the connection has been set up, the subscriber station receives the message signal MF from the radio concentrator and the radio concentrator receives the message signal MT from the subscriber station. When this signal is received, the subscriber station or the radio concentrator recognizes that on the one hand the frame synchronism is still guaranteed and on the other hand the speech connection between the radio concentrator and the subscriber station still exists. If the subscriber station or the radio concentrator does not receive a message signal MF or MT over a certain number of time slots C, the speech connection is triggered automatically by the subscriber station or by the radio concentrator. In the next time slot C, the subscriber station leaves the voice channel and listens to one of the other organizational channels. In Fig. 4 this period is designated FP.

The actual message flow is basically interrupted in time slots C in the voice channel. However, this interference is eliminated in that the transmission speed on the radio link is increased and, at the transmitting and receiving end, intermediate memories for the message signals are provided both at the subscriber station and at the radio concentrator, with the aid of which the gaps are bridged. If the call is ended by the calling subscriber, the radio concentrator F2 sends a shutdown signal AF over the voice channel in the following time slot C, which is acknowledged by the subscriber station T in the two subsequent time slots A and B with the shutdown signals AT, whereby the connection is terminated. On the other hand, if the called subscriber T ends the call, as is indicated in connection with the functional sequence according to FIG. 5, the subscriber station T sends a shutdown signal AT via the voice channel in the following time slot C, which in the two following time slots A and B from the radio concentrator with the Shutdown signals Af is acknowledged, whereby at least the radio connection is broken.

5 shows the case in which the subscriber station T registered with the radio concentrator F2 of the radio area 2 issues a call for a connection request. Since the subscriber station T wants to make a call, it receives the information V about a certain number of free operating channels from the perspective of the radio concentrator via the organization channel in a quasi-randomly rolled time slot A and starts the free search FS in the following time slot B from the collective of the channels communicated by the radio concentrator to determine the best free operating channel from their own radio technology perspective and then reports this to the radio concentrator in the organization channel. This message in connection with the call is called RT. The time slot for issuing the call RT is thus determined indirectly via the quasi-randomly rolled time slot for listening to the information V. She then leaves the organizational channel and switches to the GK voice channel she has proposed. The radio concentrator F2 already acknowledges this call with the signal QF in the voice channel GK. The connection is thus established and the message exchange can be carried out, as already indicated in FIG. 4.

If the call is ended by the calling subscriber, the subscriber station T sends a shutdown signal AT via the voice channel in the following time slot C, which is acknowledged by the radio concentrator F2 with the shutdown signals AF in the two subsequent time slots A and B, with which the connection is terminated. If the called remote subscriber ends the call, the call end status of the remote subscriber can be recognized on the radio concentrator or signaled to the radio concentrator via the switching network located behind it. The radio concentrator then sends a shutdown signal AF via the voice channel in the following time slot C ', which is acknowledged in the two following time slots A and B by the subscriber station T with the shutdown signals AT, whereby at least the radio connection is released.

4 and 5 it is assumed that the subscriber station for a free channel search FS only leaves the organization channel after a call or a call request has been made. As already pointed out, it can make sense to carry out the free search from the collective of the channels reported as free by the radio concentrator after each reception of information V in order to shorten the connection establishment when a call or

to achieve a call request. Each subscriber station registered with a radio concentrator must be periodically checked by the radio concentrator to determine whether it can still be reached. The corresponding radio organizational process is shown in FIG. 6. The subscriber station T first receives the information block K in the organization channel in the time slot C and a few time slots further in a time slot B the message call MF, which it acknowledges with the message MT in the next but one time slot B. Furthermore, within the same frame period, it receives information V about the free operating channels reported by the radio concentrator. At the beginning of the next frame, it leaves the organization channel in time slot C in order to check one of the organization channels of another radio area for its accessibility in terms of radio technology. This happens frame by frame in the interplay already described. The MF call, however, does not occur during each frame period, but at much larger intervals. The reason for this is that the possible number of subscriber stations that can register with a radio concentrator is considerably larger than the number of time slots B that are available for this within a frame period. The cycle for the call to the registered participants5

10th

15

20th

25th

30th

35

40

45

50

55

60

65

9

625 653

In other words, merstations extends over a larger number of frame periods, which is also permissible since, in contrast to, for example, the radio-organizational functions such as call, identification and registration, it is generally sufficient if the presence check is carried out only in cycle 5 of several frame periods becomes.

7 shows the case in which the unoccupied subscriber station T registered with the radio concentrator of radio area 2 is forced to re-register to another radio concentrator. In FIG. 7 it is assumed that the subscriber station registered with the radio concentrator F2 has determined in the course of its routine check that it has to avoid the radio concentrator F7 of the radio area 7 if its accessibility in terms of radio technology should continue to be guaranteed. 15 It therefore listens to the organizational channel of the radio concentrator F7 at the next start of the frame in time slot C and receives the information block with the identifier and the information about the occupancy status. It then immediately switches back to the organization channel of the radio concentrator F2. In a later quasi-randomly rolled time slot A, it transmits the reregistration Um to the organization channel of the radio concentrator F7, which is acknowledged in the following time slot B with the call MF for this radio concentrator. The subscriber station T acknowledges this with the message MT in the following time slot B and is thus registered with the new radio concentrator F7. The rest of the procedure corresponds to that of FIG. 3. It is not necessary to log off from the radio concentrator F2, since this automatically deletes the subscriber station in its memory if it does not respond to the call to it within a predetermined time. However, it can be carried out via a signaling exchange which takes place directly between the radio concentrator F7 and the radio concentrator F2. 35

The radio organizational process, which is shown in FIG. 8, describes the avoidance of a subscriber station occupied with a connection from the radio concentrator F2 to the radio concentrator F7. Below the time slots ZS, the voice channel GK is initially shown in the direction from the radio concentrator F2 to the subscriber station. The cross-hatching indicates the message flow that is interrupted in time slots C for the delivery of messages MF. The voice channel GK in the direction from the subscriber station T to the radio concentrator F2 is shown at the fifth place from above. 45 The subscriber station, which has determined that it has to avoid it and has already selected the radio concentrator F7 for this purpose, leaves the voice channel at the beginning of a frame and listens to the information block K in the organization channel of the radio concentrator F7 in time slot C. Then it receives the information V about the operating channels released by the radio concentrator F7 in a quasi-randomly rolled time slot A and then immediately proceeds in the following time slot B to check the radio channels for their suitability in terms of radio technology. In FIG. 8, this time period is again designated FS. The subscriber station then sends the call RTu in a time slot A in the organization channel to the radio concentrator F7 to reregister the existing connection, while simultaneously naming the free operating channel desired by it. The radio concentrator F7 acknowledges this message in the desired voice channel with the waiting message W. These re-registration procedures in time slots A and B generate a brief disturbance in the message flow. The subscriber station then jumps back to the original voice channel of the 65 radio concentrator F2, thus maintaining this connection. In Fig. 8 this is indicated by the double arrows. At the beginning of each new frame, the subscriber station T listens to it in the time slot C from the radio concentrator F7, which sends the waiting signal W in the time slot C until the connection is set up from the radio concentrator F2 to the radio concentrator F7. In the time slot of the waiting signal W, the subscriber station sends the message Mt. With the receipt of the message signals MT sent by the subscriber station T in the time slots C, the radio concentrator F7 recognizes that the connection to the subscriber station is still maintained. Once the new connection has been established, the radio concentrator F7 sends the signal C3 to the subscriber station T via the voice channel in the following time slot C, in which it is announced that the switchover takes place at the beginning of the frame period after next. In time segment C of the following frame, the radio concentrator F7 sends the signal C2, which indicates to the subscriber station that the switchover takes place at the beginning of the next frame period. At the beginning of the following frame, the radio concentrator notifies the subscriber station of the signal C1, which represents the time of the switchover.

This completes the switchover and the connection is maintained over the voice channel provided by the F7 Sur radio concentrator.

The signals C3, C2 and Cl represent a kind of “count down” which ensures that even if the switchover signal Cl is received incorrectly, the subscriber station still switches over if it has received one of the two preceding signals C2 or C3.

FIG. 9 shows an exemplary embodiment for a radio network with radio areas with a large number of channels of the associated radio concentrators, in which the various radio organizational functions are distributed over several organizational channels.

In the exemplary embodiment according to FIG. 9, each radio area has four organizational channels, namely the organizational channel KK for identification and first registration, the reporting channel MK for the presence check of registered subscriber stations, the call transmission channel RsK and the call reception channel ReK. 9 also shows an operating channel BK in the direction from the radio concentrator F to the subscriber T and the operating channel BK 'in the opposite direction from the subscriber T to the radio concentrator F.

Of the four organization channels, the organization channels KK, RsK and ReK have the frame period x and are divided into 32 time slots, of which time slot 1 each has the information block K. The reporting channel MK also has the information block K at intervals of the frame period x, and is aer by n (for n a whole positive number) frame lengths greater than the other organizational channels. This is necessary in order to accommodate the necessary reporting places for a maximum number of subscriber stations that can register with the radio concentrator. Within a frame period x, the reporting channel MK contains 124 reporting places, with the exception of the information block K. The length of the reporting channel MK is expediently made dependent on the traffic load, i. H. that with a decreasing number of registered subscriber stations, registration places with a high number of orders are rebooked into registration places with a low number of orders, so that depending on the volume of traffic, the cycle of a presence check of the registered subscriber stations comprises a different number of frame periods.

The call send channel RsK and the call receive channel ReK also comprise 32 blocks per frame period x, like the organization channel KK, of which blocks 2 to 32 can optionally contain calls R or messages B about the occupancy status of the radio concentrator. The call reception channel ReK is used to communicate connection requests from the subscriber stations to the radio concentrator. The risk of blocking the call reception channel ReK

625 653. 10th

Accumulation of time from the concentrator delivered to the radio concentrator.

Call messages from the subscriber stations are, as has already been done, the function module ESB is used to calculate the amount that has been carried out, by preventing every participant starting conditions. At the beginning of the establishment phase of a dialogue, a scrambler is assigned to the merstation, who is responsible for each new one between the radio concentrator and a participant.

Call message redefines one of the time slots for issuing the call message from the transmitted subscriber number of the participant. merstation the starting conditions for the obfuscation

10 and 11 are finally a direction VS from each. In this way, extensive block diagrams of a radio concentrator and a subscriber storage device for the code keys of all internal stations for digital signal transmission in duplex operation half of the radio network of existing subscriber stations can be entered, on the basis of which the practical implementation of the Verio is saved.

driving according to the invention are further clarified The functional module KV is for the operating channel

should. administration of the radio concentrator. In it the bele

The radio concentrator according to FIG. 10 correspondingly shows and manages the supply state or free state of the 120 channels of inscribed representations for a radio network according to FIGS. 1 and 2120. It identifies only those channels as free that

Voice channels GK, of which the voice channel GKI is neither a useful signal nor an impermissibly high one, while the voice channels GK2 to 120 are only occupied with interference levels. Free usable operating channels are indicated. The voice channels are of course also suitable for the transmission of data and other information to the subscriber stations via the organization channel OK. divided.

Each voice channel has a send / receive switch WE. The organization channel OK differs in its

via which the transmitter S and the receiver E are connected to the structure of a voice channel GKi due to the lack of the antenna shown. Transmitter and receiver VS VS, since the radio organizational are connected to the synthesizer SY, in which the information does not need to be concealed. Also the

Voice channel for both transmission directions assigned organizational channel OK no speed converter GW frequencies are generated. The receiver E is outgoing. The flow of information in both directions is immediately downstream of the regenerator RG that handles the regeneration and the clock phase of the receiver bar, which handles catch signals, and the function module SS is used to control the transmitter. It is followed by a runtime normalization circuit LN. switches the 120 transmitters S of voice channels KG1 to GK120. The runtime normalization circuit has the task of switching on or off as required.

different reception frame phases, for example up to The KE functional module generates the information

Can be ± 3 bits on the radio concentrator frame block 30, which is to be standardized in the organization channel OK at the beginning of each frame phase. In this way, the transmission is transmitted to the subscriber stations. The conditional phase shifts eliminated. Information block includes the identification block of the radio concentration

The obfuscation device VS, which is common to the transmitter and gate as well as information about the busy state of the radio channel and the receive path, bears the fact that the center of the data is based on the messages, to what extent the message states that in radio telephony the telephone secret only has 35 capacities is exhausted, an indication of the middle Bele-can be preserved when the message signals degree of delivery of the voice channels and an indication of whether veiled transmission. Limit the concealment device - all voice channels are currently occupied. From the VS device, the speed converter is connected upstream of the indication of the average occupancy rate of the Sprachka-GW and upstream in the transmission path. In the transmission direction channels, the subscriber stations obtain criteria as to whether the speed converter GW increases the bit rate of the information they are transmitting to another radio concentrator, for example from 4.8 kbit / s, if possible. The information block still gives 5.4 kbit / s. The time slots C in the subscriber stations thus released a message about the frame phase. As part of the organizational channel, the gaps can also contain other information of general interest that was originally a continuous flow of messages.

The signaling information is filled in, which is processed in the data backup 45 The function module RV controls the sending and payment DS. In the reception path, the catching of calls and the triggering and logging-in speech signaling information following the passage of the subscriber stations in connection with the establishment of signal flow through the obfuscation device VS of the removal and removal of connections.

The function module MN finally represents a signaling continuous signal flow of 5.4 kbit / s in the original 50 device, by means of which the booking of first and re-switching continuous signal flow of 4.8 kbit / s s implemented. fertilize as well as the ongoing presence check and training

The data security device DS, in which the signaling of subscribers takes place. The logout takes place when the information for the outgoing signal flow to signaling - the presence check has been carried out several times without success, has been put together and has been error-protected, or a transfer command from the switching center has been received and the 55 received in the receive path.

Signaling blocks, recognizes transmission errors and takes the multiplex device MUX shown in FIG. 10

if necessary, a correction. The device connected to the data security for the 120 voice channels GKI to GKI 20 forms the bridge to the device DS for the signal switching center MSt, which essentially consists of the signal processing SV for routinely performed radio organizing device SE, the switching matrix KF and the control unit is responsible for organizational processes. It winds up the signal repetition 60 SW. In order to indicate that the switching system, the resolution detection and reporting procedures from and mostly MSt cooperate with other functional units, the open positions shown by three double arrows in FIG Radio concentrator control line connections specified.

tion FS cooperating affected function block- The block diagram of a subscriber station according to Fig. 11 pen. It in turn receives corresponding signals, it also has one for the transmitter S and the receiver El

The clock center TZ, which is only indicated in FIG. 10, is on for the transceiver WE, via which the two units are used to generate the clocks and frame structures and for which the antenna AN 1 is connected. To carry out clock distribution on the various modules of the radio of a diversity reception mode, the subscriber station has

11 625 653

a second receiver E2, which is spatially connected to the functional module MN '.

Signaling device required for antenna AN2 installed separately from antenna AN 1. They work together through them. The outputs of both receivers El and E2 also change registrations.

work together with the diversity combiner DC, which has the function modules MN ', RV', SYS, FA and FE

Received level of both receivers and the signal jitter measures. s work with the higher-level central control unit ZS

Corresponding to the voice channels GK of the radio concentra-, which are expediently implemented by a microprocessor according to FIG. 10, the transmitter S and the receiver El and are realized.

E2 interconnected with the synthesizer S Y, which generates the various desired frequencies. The microphone M and the receiver H of the subscriber station are connected to the responsible input via analog / digital converter A / D.

the function module SYS is controlled. The clock center io or output of the speed converter GW connected.

TZ is connected via the DC diversity combiner- BT sets the busy controlled by the central control unit ZS-

synchronized regenerator RG. Correspondingly represents the speech-tone generator, which always responds when a

channels GKI to GKI 20 according to FIG. 10, the local link also does not have to be set up for radio-technical reasons. Merstation together for the send and receive direction can or cancels. With the analog-digital converter A / D, the

Veiling device VS, a speed wall is connected downstream of the microphone M, the free tone generator

ler GW and a data backup device DS. FTO gate, which is also operated by the central control unit ZS

The diversity-controlled works for the radio concentrator selection. The continue with the central control unit ZS

Combiner DC together with the function module FA, in cooperating ring tone generator RTO has an acoustic

which shows the reception level and the jitter criteria of the organisa- tion display L and in this way shows one of the radio con-

tion channels of the different radio concentrators collected 20 centrator calls to the subscriber station.

and for the selection of the most suitable radio concentrator for

First registration and re-registration can be evaluated. For manual operation of the subscriber station is the

The diversity combiner DC continues to work with the radio selection keyboard WT, which works together with the optical display module FE, in which the radio AZ, the selection memory WS and the operator control BS

View of the subscriber station Information on how the radio con The operating control WS is in turn connected to the central control ZS in the center of the free operating channels reported in the organizational channel.

collected and kept up to date. For the sake of completeness, there is also a device for carrying out data processing to the left of the most suitable operating channel in connection with the line.

free search to be carried out by the subscriber station. 30 drive provided, which instead of the voice operation

The functional module RV 'controls the transmission and the execution can be carried out. It consists of the data transmission capture of calls and points to the direction DÜ already described and the data terminal DE.

Throw up on.

G

10 sheets of drawings

Claims (17)

625 653 2 PATENT CLAIMS at the responsible radio concentrator (Fi) 1. Process for digital information transmission for merstation (T) immediately following this process, mobile subscriber stations in the large area of a radio network - that of the radio concentrator in the responsible organizational channel zes, which listens from several radio concentrators in a mutually continuously reported free operating channels (BK, GKi) In terms of spatial arrangement with overlapping radio areas and stores them in a memory that is constantly up to date and that a frequency distribution plan is kept up-to-date and that the subscriber station has radio concentrators, the co-channel interference in the operating channels reported as free by the radio concentrator Radio area including its overlap, as a precaution, largely excludes its radio usability range, characterized in that it checks and a number of free information that is recognized as being suitable for a radio organization congestion between operating channels in another memory, see the subscriber stations (T) and which is also kept constantly up to date with one, orderly clock synchronization working radio concentration 8. Method according to claim 7, characterized in gates (Fi) in the radio areas (1 ... 7) via central organization - that the subscriber station (T) makes the request for the operating channels (OKi, KK, MK, RsK, ReK) it makes, the connection establishment desired ( BK, that furthermore in the organizational channels from the radio 15 GKi) via the organizational channel to the radio concentrator (Fi) concentrators to the parts that can be detected in terms of radio range and that the radio concentrator periodically acknowledges this request to subscriber stations with information blocks (K) with the feedback in the desired operating channel. Radio area identification are sent, to which 9. The method according to one of the preceding claims, staggered further radio organization-related information characterized in that for the information of the connect and that the subscriber stations, insofar as they have 20 different organizational functions, such as identification, registration Fourth are eavesdropping on organizational channels, the quality of the dung, re-registration, attendance check, occupancy and reputation Check the radio connection and, taking into account each radio concentrator, a total organization channel (OKi) is available from the radio concentrators via the organizational channels, which this information in a time additionally received information on the traffic volume complex summarizes that the start of the frame also decides which of the radio areas they assign 25 of the summation organization channel to be marked by the information block or when they want to change the radio area (K) and that the summation organization channel is marked for and for the implementation of this Decisions then be made in dialogue with the attendance check of one yourself over two and more Bring radio concentrators across the organization channels - frame, in their position to the temporally fluctuating adaptable superframe use 2. The method according to claim 1, characterized in 30 makes. that the exchange of information between the radio concentra- 10. The method according to claim 9 for digital information gates (Fi) and the subscriber stations in the operating channels transmission in a radio network with a large number of channels and (BK, GKi) and the organizational channels in duplex operation with large reporting capacity of the radio concentrators, thereby he follows. marked that depending on the local traffic 3. The method according to claim 1 or 2, characterized in that a radio concentrator (Fi) has two or more sums that the subscriber stations (T) check the quality of the radio technology organization channels (OKi) with the same time-multiplexed accessibility of the different radio concentrators Men are available and that the sum organization (Fi) on the basis of the field strength and / or the phase jitter of the received channels check each other only through a traffic-related organization channels. different privileges with regard to the position 4. The method according to any one of claims 1 to 3, characterized in 40 of the subscriber states logging on to the radio concentrator that the organizational channels differ from one another from the stations (T). Radio concentrators to the subscriber stations (T) 11. The method according to claim 9, in which the information blocks (K) transmitted to the radio network in addition to the radio frequency band available for the radio network have a small band-range identifier, information about the traffic state of the broad, characterized that the Radiofre radio concentrators have. 45 sequences of organizational channels for the central area of the 5. The method according to any one of the preceding claims, radio frequency band of the radio network are defined and characterized in that the radio concentrators (Fi) their the assignment of free operating channels (BK, GKi) to the subscriber operating channels constantly with regard to their operating properties merstations (T) on request centrally by the radio control and only such free operating channels in the respective centrators. responsible organizational channels to the subscriber stations 50 12. Method according to one of claims 1 to 8, thereby transmitting (T), the radio technical characteristics of which indicate that one of the organizational channels, namely carrying out a transmission, has a sufficient quality of the reporting channel of a radio concentrator of the presence. Checking the subscribers registered in the radio area (1 ... 7) 6. The method according to any one of the preceding claims, serving stations (T) and for each registered subscriber-characterized in that one station in a radio area 55 has a time slot and that the frame period (1 ... 7) at the responsible radio concentrator (Fi ) registering this reporting channel (MK) n times, where n is a whole posi subscriber station (T) immediately following this tive number, the frame period (t) of the further organizing process, which is carried out by the radio concentrator in the responsible organizing channel or . of the other organizational channels (MS, RsK, tion channel, continuously reported free operating channels (BK, ReK). GKi) listens and stores them in a memory, which is kept up to date and that when the reporting channel (MK) discontinues a connection request in its frame period the subscriber station checks the periodically (in the frame period (x) of the other Organisa - lastly as freely reported operating channels for their radio technology channels or the other organizational channels (MK, RsK, see usability and the suitable company channels - ReK) corresponding periods of time to the swan -naligned to the radio concentrator for the establishment of the desired number of registered subscriber stations. becomes. 7. The method according to any one of claims 1 to 5, characterized ~ 14. The method according to claims 12 and 13, characterized in that one is in a radio area (1 ... 7) that a shortening of the frame period of the reporting channel (MK) when the number of registered subscriber stations decreases by regrouping the subscriber stations (T) registered in time slots with a high number of orders into unoccupied time slots with a low number of orders. 15. The method according to claims 12 and 13, characterized in that the subscriber stations (T) registered at a radio area are periodically called up by the responsible radio concentrator via the reporting channel (MK) with a period dependent on the number of registered subscriber stations for submitting presence reports. 16. The method according to any one of the preceding claims, characterized in that the presence of a subscriber station (T) registered in a radio area (1 ... 7) at the responsible radio concentrator (Fi) is automatically deleted in the memory of the radio concentrator when the subscriber station does not send a presence report to the radio concentrator within a time interval of a predetermined length via the responsible organizational channel. 17. The method according to any one of the preceding claims, characterized in that for the registration and call of subscriber stations (T) at a radio concentrator (Fi) within a frame period (t) of the responsible organizational channel, a predetermined number of discrete time slots are available, which if necessary, each of the subscriber stations can be occupied according to a pseudo-random law. 18. The method according to claim 15, characterized in that each subscriber station (T) has a frame and bit clock-synchronized scrambler, which selects one of the time slots of the responsible organization channel for occupancy on request. 19. The method according to any one of the preceding claims, characterized in that a subscriber station (T) occupied with a connection interrupts the transmission in the time intervals in which the information blocks (K) occur in the organizational channels and alternately interrupts the operational area's radio channel occupied with the connection checked for the continuation of the connection and listened to one of the organizational channels outside the radio area. 20. The method according to claim 19, characterized in that the periodic checking of the operational channel occupied by the connection is carried out by a mutual exchange of messages (MT, MF) between the subscriber station (T) and the radio concentrator (Fi) and in the absence of these messages a forced release of the connection is initiated over several test periods. 21. The method according to claim 19, characterized in that the periodic interruptions of the occupied connection when listening to the information blocks (K) of the organizational channels are eliminated by increasing the transmission speed with the radio link, in connection with a transmission and reception-side buffering the message signals to be transmitted at the subscriber station (T) and the radio concentrator (Fi). 22. The method according to any one of the preceding claims, characterized in that when initiating a necessary radio area change of a subscriber station (T) occupied with a connection, this subscriber station first listens to the channel information of the new radio area recognized as being suitable in terms of radio technology, and then contacts the associated radio concentrator (Fi) Specification of the free operating channel recognized as suitable registers that the new radio concentrator also acknowledges the message with a response prompting the subscriber station to wait, in which the subscriber station maintains the original connection via the previous radio concentrator, and also after preparation of the mediator 625653 Reallocation of the existing connection in the dialogue between the previous and the new radio concentrator, the new radio concentrator notifies the subscriber station of the time for the final switchover and that the new radio concentrator and the subscriber station then simultaneously carry out the final switchover. 23. The method according to claim 19, characterized in that the time for the final switch from the new radio concentrator is repeatedly transmitted to the subscriber station, in such a way that the respective remaining time difference is still recognizable for the subscriber station and that the subscriber station receives a properly upon receipt of these messages (C3, C2, Cl) causes the switchover at the specified time. 24. The method according to any one of the preceding claims, characterized in that the sequence of the radio organizational functions on the part of a subscriber station (T) is controlled by a microprocessor.