U.S. patent application number 12/111643 was filed with the patent office on 2008-10-23 for method and apparatus for dynamic radio resource controlling.
This patent application is currently assigned to Spyder Navigations L.L.C.. Invention is credited to Juha Rasanen, Marko Valo.
Application Number | 20080259898 12/111643 |
Document ID | / |
Family ID | 26160643 |
Filed Date | 2008-10-23 |
United States Patent
Application |
20080259898 |
Kind Code |
A1 |
Valo; Marko ; et
al. |
October 23, 2008 |
METHOD AND APPARATUS FOR DYNAMIC RADIO RESOURCE CONTROLLING
Abstract
A method and a mobile terminal for communicating with a mobile
network element (IWF) comprising communicating with a mobile
network element (IWF) using a bearer that is modifiable by a
negotiation between the mobile terminal (MS) and the mobile network
element (IWF). The data is divided into data units (60) that
comprise at least one user data element (61) and at least one
status data element (62), said status data element (62) optionally
comprising a status indication (63) from the mobile network element
(IWF) to the mobile terminal (MS). A need for bearer modification
is detected from received status indications (63) in at least two
consecutive data units; and a negotiation for bearer modification
is initiated, as a response to the detected need for bearer
modification.
Inventors: |
Valo; Marko; (Tampere,
FI) ; Rasanen; Juha; (Espoo, FI) |
Correspondence
Address: |
FOLEY & LARDNER LLP
150 EAST GILMAN STREET, P.O. BOX 1497
MADISON
WI
53701-1497
US
|
Assignee: |
Spyder Navigations L.L.C.
|
Family ID: |
26160643 |
Appl. No.: |
12/111643 |
Filed: |
April 29, 2008 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
09397300 |
Sep 15, 1999 |
7385962 |
|
|
12111643 |
|
|
|
|
Current U.S.
Class: |
370/345 |
Current CPC
Class: |
H04W 24/00 20130101;
H04W 28/18 20130101; H04W 28/06 20130101 |
Class at
Publication: |
370/345 |
International
Class: |
H04J 3/00 20060101
H04J003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 16, 1998 |
FI |
982002 |
Dec 7, 1998 |
FI |
982643 |
Claims
1. A mobile terminal comprising: a transceiver configured to
receive a plurality of data units originating from a network
element, wherein at least one data unit of the plurality of data
units includes a status bit indicating that flow control in the
network element used to transmit the at least one data unit is
active or inactive; and a data processing unit configured to
analyze the status bit; and determine whether to request a change
in a data rate at which the transceiver receives the plurality of
data units based at least in part on the analysis of the status
bit.
2. The mobile terminal of claim 1, wherein the data processing unit
is further configured to request a bearer downgrade if the flow
control is active for a predetermined amount of time.
3. The mobile terminal of claim 1, wherein the data processing unit
is further configured to request a bearer upgrade if the flow
control is inactive for a predetermined amount of time.
4. The mobile terminal of claim 1, further comprising a counter,
wherein the data processing unit uses the counter to track a number
of consecutive status bits having a same value.
5. The mobile terminal of claim 4, wherein the data processing unit
is further configured to request the change in the data rate if the
number of consecutive status bits having the same value is greater
than a predetermined threshold.
6. The mobile terminal of claim 1, further comprising a timer,
wherein the data processing unit is configured to initiate the
timer when a second received status bit differs from a first
received status bit.
7. The mobile terminal of claim 6, wherein the data processing unit
is further configured to request the change in the data rate if a
time kept by the timer exceeds a threshold value.
8. The mobile terminal of claim 1, wherein analyzing the status bit
comprises comparing the status bit to a reference value.
9. The mobile terminal of claim 1, wherein the transceiver is
further configured to receive a user initiated modification
indication, and further wherein the data processing unit is
configured to activate or deactivate the analysis of the status bit
based on the user initiated modification indication.
10. A method for determining a rate for exchanging data, the method
comprising: receiving a plurality of data units originating from a
network element, wherein at least one data unit of the plurality of
data units includes a status bit indicating that flow control in
the network element used to transmit the at least one data unit is
active or inactive; analyzing the status bit; and determining
whether to request a change in a data rate at which the plurality
of data units is received based at least in part on the analysis of
the status bit.
11. The method of claim 10, further comprising requesting a bearer
downgrade if the flow control is active for a predetermined amount
of time.
12. The method of claim 10, further comprising requesting a bearer
upgrade if the flow control is inactive for a predetermined amount
of time.
13. The method of claim 10, further comprising using a counter to
track a number of consecutive status bits having a same value.
14. The method of claim 13, further comprising requesting the
change in the data rate if the number of consecutive status bits
having the same value is greater than a predetermined
threshold.
15. The method of claim 10, further comprising initiating a timer
when a second received status bit differs from a first received
status bit.
16. The method of claim 15, further comprising requesting the
change in the data rate if a time kept by the timer exceeds a
threshold value.
17. A network element for using in controlling a rate of data
exchange, the network element comprising: a transceiver configured
to provide a plurality of data units to a mobile station, wherein
at least one data unit of the plurality of data units includes a
status bit indicating that flow control used to provide the at
least one data unit is active or inactive; and receive a request
for a change in a data rate at which the plurality of data units
are provided from the mobile station, wherein the request based at
least in part on an analysis of the status bit by the mobile
station; and a data processing unit configured to change the data
rate based on the received request.
18. The network element of claim 17, wherein the data processing
unit is further configured to determine whether the flow control is
active or inactive.
19. The network element of claim 17, wherein the network element
comprises an inter-working function.
20. The network element of claim 17, wherein the plurality of data
units is provided through a plurality of data streams.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 09/397,300, filed Sep. 15, 1999, which claims
priority to Finnish Patent Application No. 982002, filed Sep. 16,
1998, and to Finnish Patent Application No. 982643, filed Dec. 7,
1998, the disclosures of which are incorporated herein by reference
in their entireties.
FIELD
[0002] The present invention relates to a method for communicating
with a mobile network element and a mobile terminal implementing
the method. The mobile terminal comprises transmission means for
communicating with a mobile network element using a bearer that is
modifiable by a negotiation between the mobile terminal and the
mobile network element, said data being divided into data units
that comprise at least one user data element and at least one
status data element, said status data element optionally comprising
a status indication from the mobile network element to the mobile
terminal.
BACKGROUND
[0003] Many existing digital wireless or mobile telephone networks
make use of time division multiple access (TDMA) to share out radio
resources between a number of mobile stations and between a number
of channels. For example, in the European Telecommunications
Standards Institute (ETSI) GSM standard, a given frequency band is
divided in the time domain into a succession of frames, known as
TDMA (Time Division Multiplexed Access) frames. The length of a
TDMA frame is 4.615 ms. Each TDMA frame is in turn divided into
eight consecutive slots of equal duration. In the conventional
circuit switched transmission mode, when a call is initiated, a
full rate bidirectional traffic channel (TCH/F) is defined for that
call by reserving two time slots (1 to 8), in each of a succession
of TDMA frames, for the duration of the call. One of these slots
provides the downlink from the base station (BS) to the mobile
station (MS) whilst the other provides the uplink.
[0004] The circuit switched transmission mode in GSM provides for a
data transmission rate of 9.6 kbps. However, due to the demand for
higher transmission rates, a set of GSM enhancements known as GSM
Phase 2+ have been specified by ETSI. One of the main features of
GSM Phase 2+ is known as High Speed Circuit Switched Data
(HSCSD--specified in GSM 02.34 and GSM 03.34) which achieves an
increased data transmission rate by using more than one TCH/F for a
single connection (i.e. effectively reserving two or more
consecutive time slots in each TDMA frame).
[0005] In GSM HSCSD non-transparent connection mode the user can
(if the MS supports this feature) request service level up- or
downgrading, i.e. request more or less time slots to be allocated
for a connection. Provided that the feature is requested in the
set-up of a call, service level up- and downgrading is possible
during an ongoing call. For example, when setting up a connection
to an Internet Service Provider (ISP), the login and authorisation
procedures do not require a lot of transmission capacity and could
therefore be managed with one time slot connection. When the
connection is established and a large file or a www-page (World
Wide Web) containing graphics is being downloaded, more
transmission capacity is needed. When the file or the www-page are
downloaded and the user is reading the information, the need for
capacity is not that big anymore, and a small number of time slots
are needed.
[0006] The advantage of using a correct amount of capacity, i.e.
correct number of time slots at each time draws from the fact that
the user pays for the connection depending on the amount of time
slots used. The less capacity is used, i.e. the less time slots are
wasted, and the less the user has to pay. In addition, this
approach is advantageous also with respect to the network, since
the same resources can be used to facilitate services for a
remarkably larger number of users.
[0007] However, until now the initiative of radio resource
modification (e.g. capacity) is left to the user, which means that
in order to be able to properly utilise said radio resource
modification, the user should be able to perform relatively
complicated call control procedures. On the other hand, the
protocols between a mobile station and network entities have been
quite definitely specified in the standards, and any new solutions
for easier assessment of radio resource modification that require
changes to existing standards and/or to existing mobile network
elements are not very satisfactory.
[0008] Furthermore, to facilitate such up- or downgrading of
service level, also the application running in the MS must be
adapted to support this feature. This means that for example, a
www-browser or an email application in the MS must be adapted to
recognise that the connection used is a GSM connection employing
multiple time slots, and that service level up- and downgrading is
supported by the mobile. So far no such applications exist, and
even if some such applications were created, mobile subscribers
would always be limited to those few adapted applications
available.
SUMMARY
[0009] Now, a method and a device have been invented, with which
the effect of these problems can be considerably reduced.
[0010] According to the first aspect of the invention the mobile
terminal comprises detecting means for detecting a need for bearer
modification from received status indications in at least two
consecutive data units; and control means for initiating a
negotiation for bearer modification, as a response to the detected
need for bearer modification.
[0011] In the solution according to the invention, the mobile
terminal is arranged to analyze the received data flow, and using
the existing information therein to decide whether a correct radio
resource is used for the transmission or not. If the radio resource
is insufficient, the mobile terminal will initiate negotiations for
radio resource upgrading. If the radio resource is excessive, the
mobile terminal will initiate negotiations for radio resource
downgrading.
[0012] Consequently, radio resource modifications can be
implemented automatically without the user or the data processing
entity connected to the MS necessarily being involved with the
control of the properties of the radio resource. Accordingly, the
present invention enables easy utilisation of the dynamic nature of
the data link.
[0013] According to a second aspect of the invention a method for
communicating with a mobile network element is presented. The
method comprises communicating with a mobile network element using
a bearer that is modifiable by a negotiation between the mobile
terminal and the mobile network element. The data is divided into
data units that comprise at least one user data element and at
least one status data element, said status data element optionally
comprising a status indication from the mobile network element to
the mobile terminal. The method is characterized by detecting a
need for bearer modification from received status indications in at
least two consecutive data units; and initiating a negotiation for
bearer modification, as a response to the detected need for bearer
modification.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] For a better understanding of the invention and in order to
show how the same may be carried into effect reference will now be
made, by way of example, to the accompanying drawings, in
which;
[0015] FIG. 1 illustrates the basic elements of the GSM system
(state of the art);
[0016] FIG. 2 illustrates a generalised implementation of HSCSD
services in the GSM network (state of the art);
[0017] FIG. 3 illustrates an example of the signalling in GSM
HSCSD, associated with the user initiated service level up- and
downgrading procedure (state of the art);
[0018] FIG. 4 illustrates the functional elements of the data
transfer process in GSM (state of the art);
[0019] FIG. 5 illustrates the structure of a RLP frame;
[0020] FIG. 6 illustrates an example of a L2R Packet Data Unit
(PDU);
[0021] FIG. 7 illustrates the functionality of a MS according to
the invention;
[0022] FIG. 8 illustrates an embodiment for controlling the radio
transmission in the downlink direction; and
[0023] FIG. 9 illustrates functional modules of a mobile terminal
according to the invention.
DETAILED DESCRIPTION
[0024] The invention will, by way of an example, be described in
connection with GSM (Global System for Mobile Telecommunications)
system using the terms and elements traditionally appearing in this
context. Further embodiments in functionally equivalent mobile
communication system environments are naturally possible. Among the
preferred systems are, for example, GSM derivatives, like DCS
(Digital Cellular System for 1800 MHz) and PCS (Personal
Communications Service for 1900 MHz).
[0025] FIG. 1 illustrates the basic elements of the GSM system.
Mobile stations MS are in connection with base stations BTS using
radio communication. The base stations BTS are further, through a
so-called Abis interface, connected to a base station controller
BSC, which controls and manages several base stations. The entity
formed by several base stations BTS and a single base station
controller BSC controlling them are called a base station
sub-system BSS. Particularly, the base station controller BSC
manages radio-communication channels, as well as handovers. On the
other hand, the base station controller BSC is, through the so
called A interface, in connection with a mobile services switching
centre (MSC), which co-ordinates the establishment of connections
to and from mobile stations. Through the mobile services switching
centre MSC, a connection can further be established to a subscriber
not operating under the mobile communication network.
[0026] A set of GSM enhancements specified by European
Telecommunications Standards Institute (ETSI) is called ETSI Phase
2+. One of the main work items in phase 2+ is High Speed Circuit
Switched Data (HSCSD). HSCSD is an enhancement of the current
circuit switched GSM data services to cover higher user rates than
9.6 kbps. The architecture of the HSCSD service is based on the
physical layer of the current data services. The increased data
rate is achieved by using a combination of more than one full
traffic channel (TCH/F) for a single connection.
[0027] In the transparent data transmission mode the maximum HSCSD
data rate is 64 kpbs using bit transparent protocols. In
non-transparent mode the maximum data rate is 38.4 kpbs achieved by
using a combination of four TCH/F9.6 channels. After the
standardisation of the 14.4 kbps channel coding is completed, the
maximum non-transparent data rate is increased to 57.6 kpbs. The
effective user data rate of the non-transparent HSCSD data service
may be further increased by using GSM data compression that is
based on V.42bis algorithm. This compression algorithm increase the
effective user data rate to between two and four times the physical
user data rate.
[0028] Non-transparent mode of HSCSD is realised by modifying the
RLP (Radio Link Protocol) and L2R (Layer 2 Relaying) functions to
support multiple parallel traffic channels (TCH/F) instead of only
one TCH/F, and the RLP frame numbering is increased to accommodate
the enlarged data transmission rate, as specified by the ETSI and
generally known to a person skilled in the art. FIG. 2 illustrates
a generalised implementation of HSCSD services in the GSM network.
In addition to the network elements described in connection of FIG.
1, a new functionality IWF (Inter-Working Function) is introduced
in the network side and TAF (Terminal Adapter Function) in a mobile
station. The new elements provide the functions of combining and
splitting the data into separate data streams, which will then be
carried via n channels at the radio interface. Once split, the data
streams shall be carried by the n full rate traffic channels,
called HSCSD channels, as if they were independent of each other,
for the purpose of data relay and radio interface error control,
until to the point in the network where they are combined.
[0029] To couple the Terminal Adapter Function with Interworking
control procedures, a group of GSM Bearer Capability Information
Elements (BCIE) need to be defined during the call set-up
procedure. The BCIE comprise a parameter User Initiated
Modification Indication (UIMI), which is relevant between the MS
and IWF. The value of UIMI indicates whether the user would like to
be able to modify the value of maximum number of traffic channels
during a connection, and in positive case also the maximum number
of time slots available for upgrading the connection. Among
parameters negotiated in the call set-up procedure are also the
Fixed Network User Rate (FNUR), which defines the user rate between
the IWF and the fixed network, and the Wanted Air Interface User
Rate (WAIUR) defining the air interface user rate between the MS
and IWF.
[0030] If the parameter UIMI has been given a non-zero value,
during a HSCSD call the user may request the network to change the
current maximum number of traffic channels and air interface user
rate parameters. FIG. 3 illustrates an example of the signaling in
GSM HSCSD, associated with the user initiated service level up- and
downgrading procedure. The user will initiate the procedure with a
signal 3.1 comprising the new parameters para defining the radio
resource wished for. If the network allows the modification, the
resulting new parameters are forwarded to the BSC (signal 3.2) and
the radio interface resources may be adjusted accordingly. The
resource upgrading and downgrading are done separately from the
change in HSCSD parameters. However, if a contradiction between the
new parameters and the used air interface resources exists, the
resource downgrading may be needed before the network acknowledges
the new parameters. When the procedure is finished, the BSC will
acknowledge it to the MSC (signal 3.3) and the MSC will indicate
the completion of the modification to the MS (signal 3.4).
[0031] In the system according to the embodiment of the invention,
the mobile station monitors the data flow transferred over the air
interface, and based on the monitoring results intelligently
controls e.g. the number of the time slots used for the connection.
In the following, some embodiments of the invention are discussed.
The radio resource used for a connection is hereafter referred to
as a bearer.
[0032] According to the invention the data already available in
data units is used by the MS to derive the decision whether bearer
modification is necessary. To demonstrate the structural division
of transceived information, data transfer process in a GSM system
supporting HSCSD service is studied. FIG. 4 illustrates the
functional elements of the data transfer process in GSM. Data from
the Data Terminal Equipment DTE is processed by Layer 2 Relay
function L2R, which provides for the reliable transportation of
known, i.e. non transparent, user protocols across the radio
interface of a GSM PLMN. The L2R uses the services provided by the
Radio Link Protocol (RLP) to transport the non-transparent protocol
information between the MS and the network. In FIG. 5 an example of
a RLP frame 50 is shown. The frame typically comprises a header 51,
an information field 52 and a frame check sequene 53. The
information of L2R data units is carried in the information field
52 of the frame.
[0033] The decision on whether a correct radio resource is used
could also be made in the IWF and be indicated to the MS in the
header 51 of the RLP frame. Anyhow, this seems to be an unnecessary
association between a link layer protocol and a non-link-layer
function, and as conceivably bringing about some changes to the
protocol, would not be very satisfactory.
[0034] In FIG. 6 as an example of a data unit, a structure of a L2R
Packet Data Unit (PDU) is illustrated. It comprises consecutive
octets that are data octets 61 carrying user data and status octets
62 carrying general information on the contents of the PDU and/or
the status of the connection.
[0035] The L2R and RLP entities have buffers which may become full
to a predetermined threshold for a number of reasons, e.g. severe
radio fading, failure or slowness of DTE to react to end-to-end
flow control, or certain RNR conditions. When this predetermined
threshold is reached, a flow control active condition is sent to
the associated DTE, which is then prevented from sending any data.
Subsequently, the flow control inactive condition is sent to the
associated DTE when the L2R or RLP entities have indicated that
there is sufficient free capacity in their buffers for data flow
from the associated DTE to proceed. A status octet 62 of a L2R PDU
comprises a flow control indication bit 63 indicating whether the
flow control in the DTE in the opposite end is active or inactive.
A status octet may also comprise a break indication bit indicating
that the rest of the PDU is empty, i.e. the PDU is not full of user
data.
[0036] In the solution according to the invention, the user has an
opportunity to enable or disable the use of user initiated bearer
modification. When the modification is enabled, the mobile station
according to the invention starts monitoring the contents of the
consecutively received data units, here the L2R PDUs. In the first
embodiment of the invention, the MS will especially monitor
consecutively received flow control indication bits. Whenever it
seems that the flow control in the IWU end is active for a long
period, the MS deduces that the data rate should be downgraded and
initiates a bearer downgrading negotiation. If the flow control is
not active or has not been active for some time, the MS will
initiate a radio resource upgrading negotiation. The decision, on
when the flow control is active or inactive for a long time, i.e.
when the bearer modification (upgrading or downgrading) in this
case is necessary, can be derived in many ways. Next one of the
possible ways is described.
[0037] The flow chart of FIG. 7 illustrates the functionality of a
MS according to the invention from the beginning of a set-up of a
call or from the acknowledged bearer modification. In step 710 the
reference value R equaling to the value of the received status bit
Flbit (Flow control Indication bit) that indicates the activity or
inactivity of the flow control in the IWU, is initialised. In step
715 the counter CT, which is used for storing the number of
consecutive Flbits having the same value, is initialised. After
this the first PDU is received (step 720), and the value of Flbit
is checked (step 725). The received value Flbit is compared with
the reference value R (steps 730, 735), and if they are not the
same, the reference value R will be changed (step 770). If the
Flbit is the same as the reference value R, the counter CT is
incremented (steps 740). The derived counter value CT is compared
(steps 745, 750) with the threshold value CTmax that indicates the
maximum number of consecutive flow control indication bits that are
detected before the initiation of bearer modification. If the
counter value is less than or equal to CTmax, the process will
continue from step 720 where the next PDU is received. If the
counter value CT is greater than CTmax, the MS will initiate a
negotiation for a bearer modification, as described earlier (step
760).
[0038] The embodiment of FIG. 7 is an example of a solution
according to the invention. It applies well for controlling the
radio transmission in the uplink direction. Anyhow, as mentioned
earlier, the interval of consecutive indication of flow control
before initiation of bearer modification can be implemented in many
ways. For example, a timer that is initialised each time the value
of the flow control indication bit changes can be used. It is also
possible to use different threshold values for bearer upgrading and
downgrading. For example, bearer upgrading can be initiated after a
number of consecutive bits that indicate the Flow control
inactive-status, and bearer downgrading can be initiated after a
number of consecutive bits that indicate the Flow control
active-status.
[0039] The flow chart of FIG. 8 illustrates an embodiment for
controlling the radio transmission in the downlink direction. The
PDUs comprise information indicating whether the PDU is full or
not. By monitoring such information, it is possible to derive an
estimate on the effective transmitted user data rate. If the
effective user data rate is substantially less than the full
capacity of the used channels, the MS will initiate bearer
downgrading. If, on the other hand, the effective user data rate
corresponds to the full capacity of the used channels, the MS will
try data rate upgrading. The effective user data rate can be
derived in several ways, but in the following an embodiment using
two simple counters and a timer is described.
[0040] The RLP-header of a PDU comprises a S-bit that indicates
whether the PDU comprises a status octet or not. Status octets are
inserted in the character stream 30 whenever a status change needs
to be transmitted. If the PDU is full of data, it does not comprise
the status octet. In the embodiment the effective user data rate is
derived in predefined intervals T. This means that a timer t is
running for a period of T at a time and after the elapse of the
time limit T, the estimation of effective user data rate is
restarted. In step 810 two counters SE and SF are initialised, and
in step 815 the timer t is started. In step 820 the count of the
timer t is checked, and whenever the time limit T has elapsed, the
process will go to step 845. Until the time limit T has elapsed, a
next PDU will be received (step 825) and the indication Sbit,
indicating whether the PDU comprises a status octet or not, is
checked (step 830). If in step 835 the Sbit indicates that the PDU
does not comprise a status octet, the counter SF is incremented
(step 840). If the Sbit indicates that PDU comprises a status
octet, the contents of the PDU has to be checked more thoroughly
(step 860). The status octet comprises status bits SA, SB and X,
and a 5-bit code which indicates the location of the next status
octet or that the remainder of the PDU is empty. If the indication
of the remainder of the PDU being empty is found (step 865), the
counter SE is incremented (step 870), otherwise no incrementation
is done. After step 865=No or after step 870 the process will
continue from step 820. Alternatively the step 865=No could go to
step 840 (not shown in the Figure).
[0041] When at step 820 it is noted that the time limit T has
elapsed, it continues at step 845 in which the current value of the
counter SF is divided with the reading t of the timer to derive the
rate sf at which PDUs that are full of user data are received.
Moreover, at step 875 the current value of the counter SE is
divided with the reading t of the timer to derive the rate se. Then
it is checked if the derived value of sf is greater than a
predefined threshold TH1 (step 850), and if so the MS will initiate
a bearer upgrading process (step 855). If sf is not greater than a
predefined threshold TH1 another comparison is made (at step 880)
to see if the derived value of se is greater than a predefined
threshold TH2, and if so the MS will initiate a bearer downgrading
process. If the threshold TH1 or TH2 is not exceeded, the process
will continue from step 810.
[0042] FIG. 9 illustrates functional modules of mobile terminal
according to the invention. A Central Processing Unit 91 controls
the blocks responsible for the mobile station's different
functions: a Memory (MEM) 92, a Radio Frequency block (RF) 93, a
User Interface (UI) 94 and an Interface Unit (IU) 95. CPU is
typically implemented with one or more functionally inter-working
microprocessors. The memory preferably comprises a ROM (Read Only
Memory), a RAM (Random Access Memory) and is generally supplemented
with memory supplied with the SIM User Identification Module. In
accordance with its program, the microprocessor uses the RF block
93 for transmitting and receiving messages on the radio path.
Communication with the user is managed with by the U194, which
typically comprises a loudspeaker, a display and a keyboard. The
Interface Unit 95 provides a link to a data processing entity, and
it is controlled by the CPU 91. The data processing entity may be
an integrated data processor or external data processing equipment.
The mobile terminal according to the invention further comprises
detection means 96 for monitoring the contents of the received data
flow, and based on a certain predefined property in the data flow
will detect whether the current bearer is adequate or not. The
means may comprise at least one counter that is incremented by
consecutive flow control indications, as described in connection
with FIG. 6. The means may also comprise one or more counters
responsive to the indication of full or partly full PDUs, and a
timer, as described in connection with FIG. 9. Other functionally
equivalent means are also possible. Though shown as a separate
element in FIG. 9, the means may also be integrated within the CPU.
By utilising said detection means 96 the mobile terminal is able to
automatically control the capacity used for the connection and
thereby enhance the effective use of bearer.
[0043] The above is a description of the realization of the
invention and its embodiments utilizing examples. It is self
evident to a person skilled in the art that the invention is not
limited to the details of the above presented embodiments and that
the invention can be realized also in other embodiments without
deviating from the characteristics of the invention. The presented
embodiments should be regarded as illustrating but not limiting.
Thus the possibilities to realize and use the invention are limited
only by the enclosed claims. Thus different embodiments of the
invention specified by the claims, also equivalent embodiments, are
included in the scope of the invention.
* * * * *