GB2332123A

GB2332123A - Two way radio communication system, radio unit and method of operation

Info

Publication number: GB2332123A
Application number: GB9725747A
Authority: GB
Inventors: Jens Kristiansen
Original assignee: Motorola AS
Current assignee: Motorola Solutions Danmark AS
Priority date: 1997-12-05
Filing date: 1997-12-05
Publication date: 1999-06-09
Anticipated expiration: 2017-12-05
Also published as: GB2332123A9; GB2332123B; GB9725747D0

Abstract

A radio unit (10, 12, 14, 22, 24, 26, 28, 30, 32, Figs 1 and 2) for operation in a two way radio communication system (20) is provided. The radio unit communicates via at least one communication resource (34, 36) and includes a logger 45, 46 for recording usage information of the at least one communication resource by the at least one first radio unit. The logging operation includes logging the time of transmissions by the radio unit for subsequent billing purposes. The logged information is transmitted to a central billing unit. The logging may also include recording voice transmissions of the two way communication system.

Description

0 2332123 TWO WAY RADIO COMMUNICATION SYSTEM, RADIO UNIT AND METHOD OF

OPERATION Fleld of the Invention This invention relates to two-way point-to-point radio corn milni cation systems. The invention is applicable to, but not limited to methods of recording information on communications between at least two radio subscribers and consequently being able to bill for air-time used.

Badwmund of the htion In a two way radio communication system there are often a number of communication resources, for example frequencies, time periods, coding schemes, that are available for allocating to communication system user's to enable the users to set up a communication link. In some communication systems, the radio users transmit and receive on the same radio frequency. In such a system, assuming no geographical reuse of the frequency, only one call can be established between at least two radio units at any one time. It is possible, and often implemented in multi-site systems, that the same communication resources are re-allocated on a geographical basis to some users as long as they do not interfere with existing users using that particular resource, for example where any potential interfering signal level from new users would be too low to be detected by the existing users.

In two-way radio communications systems, communication between two radios is typically performed via individual calls between two users or via group calls where users commilni to a number of other users in a particular communication group. In mobile trunked radio communication systems, the recording or logging of voice communications is carried out at a central location of the system, for example a central controller or primary base station. A central location is the optimal position for performing voice recording as all voice communications pass through such a position. An example of the necessity for logging voice communications is found in Public Safety Systems where a record of say, a police operation is logged. The information stored in such a process includes the step by step record of 0 2 actual voice communication including what information was provided, at what time, who was involved, etc.

Furthermore, in such communication systems, the registration of used talk time for a subscriber radio leads to the opportunity for the service provider to bill according to the resource usage within the system. In a Groupe Speciale Mobile (GSM) cellular communication system, a record of phone call times is logged at the central station, as communications pass through the central station, which is subsequently used for billing purposes.

In a time division multiple access (TDMA) communication system time and frequency resources are allocated to users in trunked and/or nontrunked commimi cations, for example where each frequency includes four time slots for use by four separate users. In trunked commi-Ini cation systems, use of the communi cations resource can be monitored and billed for by the service provider, by way of monitoring at the central stations communications that pass through. This is often a lucrative business, once the infrastructure and the frequencies have been purchased. In nontrunked operation, i.e. direct mode operation (DMO) in the European TETRA standard, the radio units may communicate on a particular time slot dedicated for this mode of operation. However, there is no central element in this type of communication for either monitoring the use made of the resource by radio units or for recording voice communications.

This invention seeks to provide a two-way communi on system, a radio unit for use in the two-way communication system and methods of operating the two way communication system and radio unit which mitigates at least some of the above mentioned disadvantages.

EmWklu of the According to the to a first aspect of the invention there is provided a two way radio communication system. The two way radio communication system includes a plurality of radio units communicating via at least one communication resource. At least one radio unit of the plurality of radio units comprises a logger for recording usage information of the at least one c 3 communication resource by the at least one first radio unit. In the preferred embodiment of the invention, the logger includes a time recording fiinction for monitoring the time usage of the at least one communication resource by the at least one first radio unit.

In this manner, the usage made of the available communications by the at least one radio unit can be monitored, and subsequently charged for by the communication system provider. Preferably a voice recording function is included to enable the voice communications to be stored and either retained or relayed to a central control unit at a later date, for example as would be usefi:d in Police radio situations where transmissions may be required for evidence purposes.

Preferably, the radio unit includes a processor for maintaining a list of time usage of the at least one communication resources, where the list includes at least one of. day, call start time, call duration, call end time, total call time. The radio unit further includes a transmitter to tran rnit the maintained list to a central billing unit for determining the call charge rate of the first radio unit. In the preferred embodiment of the invention, the logger can be selectively enabled according to the present usage of the two way radio communication system.

In a second aspect of the present invention a at least one first radio unit for use in a two way radio communication system, as hereinbefore described, is provided.

In a third aspect of the present invention a method of operating a radio unit in a two way communication system, as hereinbefore described, is provided.

A preferred embodiment of the invention will now be described by way of example only, with reference to the drawing.

BrW lkfficd of the]2r& FIG. 1 shows a first two way communication system according to a preferred embodiment of the invention.

FIG. 2 shows a second two way communication system according to 35 a preferred embodiment of the invention.

0 4 4 FIG. 3 shows a block diagram of a at least one first radio unit according to a preferred embodiment of the invention.

FIG. 4 is a flow chart showing a method of operating a at least one first radio unit in the two way communication system according to a 5 preferred embodiment of the invention.

Detailed 12w&r of the Dras Referring first to FIG. 1, a two-way radio cornmilni cations system is shown. Communications are typically performed via individual calls between two remote mobile/portable users or alternatively via group calls where users communicate to a number of other users in a particular communication group, as highlighted in FIG. 1 with communication group 14 containing portable radios 10, 12 and 16. Portable radio unit 10 has entered into communication on a frequency resource with portable radio unit 12, whilst portable radio unit 16 has entered into a communication with fixed portable radio unit 18. It should be noted that fixed portable radio unit 18 may be any fixed radio unit on the communi cations system.

Referring now to FIG. 2, a two way communi cation system 20 is shown that includes a plurality of at least one first radio units, for example mobile stations 22, 24, 26 28, 30 and 32. In such two way radio communication systems, the mobile stations can be arranged in groups, for example mobile stations 22 and 24 are members of a first group, mobile stations 32 and 30 are members of a second group and mobile stations 36 and 38 are members of a third group. In the preferred embodiment of the invention, the two way communication system 20 has a plurality of communication resources including radio frequencies 34 and 36, each having respective time slots (not shown) arranged in a Time Division Multiple Access (TDMA) manner. However, it is within the contemplation of the invention that other communication schemes, such as Frequency Division Multiple Access (FDAIA) or Code Division Multiple Access (CDMA) would also benefit from the present invention. A communication between mobile radio 26 and mobile radio 28 is being monitored as shown.

The communication begins at a first time period 19 followed by alternating 0 transmissions by each mobile radio before the communication is terminated at time period 21. The total duration 23 of the communication is recorded. It is within the contemplation of the invention that each mobile/portable radio unit monitors at least one time factor of a communication, such as day/date, call start time, call end time, call duration, duration of transmissions by that particular mobile/portable radio unit, total duration of a number of calls by that particular mobile/portable radio unit.

Referring now to FIG. 3, a block diagram of a mobile station 22, 24, 26, 28, 30 or 32 of FIG. 2 is shown. Preferably all mobile stations of the twoway communication system 20 monitor the transmissions each mobile station makes on either of the radio frequencies 34, 36. Each mobile station includes monitoring means 44 for monitoring the transmission activities on the radio frequency 34 or 36. An antenna 43 is connected to an antenna switch 49, for transferring received signals to a receiver block 48. A second position of the antenna switch 49 connects the antenna 43 to a transmitter block 47. The monitoring means 44 is connected to the receiver block 48 and to the processor 42. The processor 42 contains a timer 41 and is connected to the transmitter block 47 and to a memory element 46. The memory element 46, which may include the function of the processor 42, contains a list 45 of radio frequency transmissions. Processor 42 is also operably coupled to a speech coder for encoding and decoding speech signals to be transmitted from, or received by, the radio unit.

In a first operation of the radio wift, a communication between mobile radio 26 and mobile radio 28 is monitored by monitoring means 44.

The monitoring means 44 monitors here a call is initiated and passes this information to the processor 42. The processor 42, with a time stamp provided by the timer 41, then records timing information of that call to the list 45 in the memory element 46. This information may include: other party calling ID, day/date, call start time, call end time, call duration, duration of transmissions by that particular mobile/portable radio unit, total duration of a number of calls by that particular mobile/portable radio unit.

c 6 In a second, perhaps alternative, operation of the radio unit, voice communication between mobile radio 26 and mobile radio 28 is recorded by memory element 46. The memory element 46 records transmitted voice signals and/or received voice signals, as provided by the encoding or decoding operation of the speech coder. Such information may be stored with a time stamp, as provided by the timer 41. In the TETRA system, such recording of voice communications can be readily performed as the voice information is often in compressed form. This allows a large number of voice transmissions to be recorded in a limited memory space. Preferably, the voice recording is linked in with a Voice Activation Detection system, either in the transmit and/or receive path, to further limit the amount of voice communication to be stored. Once stored, the recorded voice information can then be transferred to some fixed point, by means of a wireline connection or via over-the-air transmission, as shown in FIG. 1 with the communication between radio unit 16 and radio unit 18.

An over-the-air transmission download of recorded voice transmissions, or time usage, may be implemented whenever the communication system is lightly loaded with regard to traffic communication and the radio unit is within communication range of the fixed unit. This invention also offers the service provider to charge different rates for usage of the communication resource during different time periods or say, on week-ends. Such an opportunity to bill, and bill at different rates, greatly assists the service provider in regulating and controlling the use of the resource.

It is within the contemplation of the invention that other radio function arrangements can be used to provide a similar voice logging fimction. It is also within the contemplation of the invention that the service provider may provide one allocated receiver (portable, mobile or base station) to each communication resource, e.g. frequency, for logging all of the voice COMMUnications on that particular frequency. This could include recording all voice transmissions and/or recording the time periods that particular users utilise that frequency, by way of using their call ID.

The method for operating a voice logging function in the mobile/portable radio unit will now be described with reference to FIG. 4.

In the preferred embodiment, the communication system is a Time 0 7 Division Multiple Access (TDMA) communication system, having a number of frequency channels, wherein each radio frequency is divided into four time-slots. The method of operating a radio unit in a two way radio communication system includes setting up a call with another radio unit, as in step 100. If voice messages are to be recorded, as shown in step 102, the radio unit transmits on the at least one communication resource and stores samples of the transmitted and/or received speech in a memory element, as in step 104. If the call time factors are to be monitored and stored, as in step 106, the timer 41 in the processor 42 is started, and the time used tran mitting, and perhaps receiving, on the at least one communication resource by the radio unit is monitored and stored, as shown in step 108. The stored call time factor data may include at least one of. details of the other party's callin ID, day, date, call start time, call duration, call end time, total call time. Once the call is terminated in step 110, the radio preferably checks to see whether it is connected to, or within range of a fixed voice logging or billing radio. If it is connected to such a radio, or within range, the radio unit may transmit the stored information to a fixed central unit for either storing the recorded voice centrally and/or determining the call charge rate to be billed to the radio unit, as shown in step 112.

As shown in FIG. 4, the operation of the voice recording fimction or call time factor monitoring function can be selectively enabled. Such a feature is beneficial in order to further control the amount of information to be stored in the radio unit. Furthermore, it is within the contemplation of the invention that such enabling of these fimctions can be initiated either by wireline or via over-the-air transmissions. This enables for example, a fixed unit of a police radio system to remotely initiate a voice monitoring or voice recording functions in a remote radio immediately to record communications in an emergency situation.

In this manner, a two way communication system, a method of operating the two way communication system and a radio unit for use in the two-way communication system are provided which mitigate at least some of the aforementioned disadvantages with present communications systems.

0

Claims

8 Claims

1. A two way radio communication system having a plurality of radio units communicating via at least one communication resource wherein at least one first radio unit of the plurality of radio units comprises: a logger for recording usage information of the at least one cornmilnication resource by the at least one first radio unit.

2. A two way radio communication system according to claim 1 wherein the logger includes a time recording function for monitoring the time usage of the at least one communication resource by the at least one first radio unit.

3. A two way radio communication system according to claims 1 or 2, wherein the at least one first radio unit further comprises a processor for maintaining a list of time usage of the at least one communi cation resources.

4. A two way radio communication system according to claim 3 wherein the maintained list of the at least one first radio unit includes at least one of. other party calling ID, day, date, call start time, call duration, call end time, total call time.

5. A two way radio communication system according to any one of the preceding claims, wherein the at least one first radio unit further comprises a transmitter to transmit the maintained list to a central billing unit for determining a call charge rate of the at least one first radio unit.

6. A two way radio communication system according to any one of the preceding claims wherein the logger further includes a voice recording function for recording voice transmissions on the two way radio communication system.

0 9

7. A two way radio communication system according to claim 6, wherein the at least one first radio unit further includes a receiver for receiving voice transmissions on the two way radio communication system and the logger includes a voice decoding element operably coupled to the receiver and a memory element for storing said voice transmissions after they have been received and decoded.

8. A two way radio cornrn i ini cation system according to claim 6 or 7, wherein the logger records voice transmissions between the at least one 10 first radio unit and any other radio unit of the plurality of radio units.

9. A two way radio communication system according to any one of preceding claims 6 to 8, wherein the at least one first radio unit further comprises a transmitter to transmit the stored logger information to a central unit over the air or via a fixed communication link-

10. A two way radio communication system according to any one of the preceding claims wherein the logger can be selectively enabled according to usage of the two way radio communication system.

11. A two way communication system as claimed in any one of the preceding claims wherein the at least one communication resource is a frequency channel and the communication system is a Time Division Multiplex Access (TDMA) communication system operating in a direct 25 mode of operation (DMO).

12. A radio unit for use in a two way radio communication system according to any one of the preceding claims.

13. A radio unit for use in a two way radio comirnuni cation system, the radio unit comprising a logger for recording usage information of at least one comrniiini cation resource on the two way radio communication system by the radio unit.

0

14. A radio unit according to claim 13 wherein the logger includes a timer recording function for monitoring the time usage of the ah- least one communication resource by the radio unit.

15. A radio unit according to claims 13 or 14, further comprising a processor for maintaining a list of time usage of the at least one communication resource.

16. A radio unit according to any one of preceding claims 13 to 15 10 wherein the maintained list of the radio unit includes at least one of. other party calling ID, day, date, call start time, call duration, call end time, total call time.

17. A radio unit according to any one of preceding claims 13 to 16 15 wherein the radio unit further comprises a transmitter to transmit the maintained list to a central billing unit for determining the call charge rate of the at least one first radio unit.

18. A radio unit according to any one of preceding claim 13 to 17 wherein 20 the logger further includes a voice recording function for recording voice transmissions on the two way radio communication system.

19. A radio unit according to claim 18 wherein the radio unit includes a receiver for receiving voice transmissions on the two way radio communication system and the logger includes a voice decoding element operably coupled to the receiver and a memory element for storing said voice transmissions after they have been received and decoded.

20. A radio unit according to claim 18 or 19, wherein the logger records 30 voice transmissions between the radio unit and any other radio unit of the plurality of radio units.

21. A radio unit according to any one of preceding claims 18 to 20, wherein the radio unit further comprises a transmitter to transmit the 0 11 stored voice transmissions to a central unit over the air or via a fixed communication link.

22. A radio unit according to any one of the preceding claims 13 to 21, wherein the logger can be selectively enabled according to the present usage of the two way radio communication system.

23. A method of operating a radio unit in a two way radio cornTniini cation system having a plurality of radio units communicating via at least one communication resource the radio unit including a processor, the method comprising the steps of.. transmitting on the at least one communication resource by the radio unit; and recording usage information by the processor of the at least one communication resource used by the radio unit.

system; and

24. A method of operating a radio unit in a two way radio communication system according to claim 23, the method further comprising the step of' 20 maintaining a list of time usage of the at least one communication resources, the maintained list including at least one of. other party calling ID, day, date, call start time, call duration, caU end time and total call time.

25. A method of operating a radio unit in a two way radio 25 communication system according to claim 24, the method further comprising the step of. transmitting the maintained list to a central billing unit for determining the call charge rate of the radio unit.

26. A method of operating a radio unit in a two way radio communication system according to any one of preceding claims 23 to 25 further comprising the steps of.

receiving voice transmissions on the two way radio communication C.

12 recording voice transmissions to or from the radio unit on the two way radio communication system.

27. A method of operating a radio unit in a two way radio communication system according to claim 26, wherein the radio unit includes a voice decoding element operably coupled to a receiver and a memory element, the method further comprising the step of. storing voice transmissions in the memory element of the radio unit after they have been received and decoded.

28. A method of operating a radio unit in a two way radio communication system according to claim 26 or 27, wherein the radio unit further comprises a transmitter, the method further comprising the step oftransmitting the stored voice transmissions to a central unit over the air or via a fixed comirnil ni cation link.

29. A method of operating a radio unit in a two way radio communication system according to any one of preceding claims 23 to 28, the method further comprising the steps of. selectively enabling the voice monitoring or voice recording functions according to the present usage of the two way radio communication system.

30. A communication system substantially as hereinbefore described with reference to, or as illustrated by, FIG. 1 or FIG. 2 of the drawings.

31. A radio unit substantially as hereinbefore described with reference to, or as illustrated by, FIG. 3 of the drawings.

32. A method of operating a communication system substantially as hereinbefore described with reference to, or as illustrated by, FIG. 4 of the drawings.