Title: Command processing method and radio communication apparatus
Abstract: A command processing method for a radio LAN system composed of a plurality of terminals and at least one base apparatus is disclosed which prevents users of the terminals from suffering from confusion or conflict between them with regard to handling of a command issued from any of the terminals and from misunderstanding that the system has failed. When a channel changing command or a like command is issued from a terminal, the base apparatus determines whether or not the received command is a competitive command whose acceptance may result in the disturbance of reception of data of any other terminal. If the received command is a competitive command, then the base apparatus rejects the command and issues a notification of the rejection to the terminal which has issued the command. When a particular condition is satisfied such as when the priority of the terminal which has issued the command is higher than that of any other terminal receiving data, then the base apparatus may accept the command.
Patent Number: 7,020,117 Issued on 03/28/2006 to Nire
| Inventors:
|
Nire; Katsuo (Saitama, JP)
|
| Assignee:
|
Sony Corporation (Tokyo, JP)
|
| Appl. No.:
|
955339 |
| Filed:
|
September 17, 2001 |
Foreign Application Priority Data
| Sep 19, 2000[JP] | 2002-283847 |
| Current U.S. Class: |
370/338; 370/462 |
| Current Intern'l Class: |
H04Q 7/24 (20060101) |
| Field of Search: |
370/328,338,310,349,401,410,351,352,353,354,355,356
|
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|
Primary Examiner: Patel; Ajit
Assistant Examiner: Lee; Andrew C.
Attorney, Agent or Firm: Frommer Lawrence & Haug LLP, Frommer; William S.
Claims
What is claimed is:
1. A command processing method for a radio LAN (Local Area Network) system which
includes a plurality of terminals and at least one base apparatus and wherein a
command issued from any of said terminals is received by said base apparatus and
information is transmitted from said base apparatus to one or more of the plurality
of terminals by radio communication between the terminals and said base apparatus,
said method comprising the steps of:
receiving commands issued from any of said terminals, said commands comprising
both competitive commands and non-competitive commands;
determining whether the received command is a competitive command whose acceptance
can result in a disturbance of information reception of any other of said terminals;
rejecting acceptance of the command if it is determined that said received command
is a competitive command; and
issuing a notification of the rejection of the command to the terminal that has
issued the command;
whereby the disturbance caused by an acceptance of a competitive command to other
terminals that are under a receiving state is minimized.
2. The command processing method of claim 1, further comprising the steps of:
setting a priority order among said plurality of terminals;
if it is determined that said received command is a competitive command, determining
whether said priority order of said terminal issuing said command is higher than
that of any other of said terminals currently receiving data;
if it is determined that said priority order of said terminal issuing said command
is higher than that of any other of said terminals currently receiving data, accepting
said command; and
issuing a notification of said acceptance of said command to said other terminals
currently receiving data.
3. The command processing method of claim 1, further comprising the steps of:
setting a predetermined time interval;
if it is determined that said received command is a competitive command, determining
whether said predetermined time interval has elapsed since the issuance of a command
implementing a procedure currently in operation;
if it is determined that said predetermined time interval has elapsed, accepting
said command; and
issuing a notification of said acceptance of said command to said other terminals
currently receiving data.
4. The command processing method of claim 1, further comprising the steps of:
inquiring of said other terminals receiving data whether a particular command
may be accepted; and
if a response to said inquiry from all of said other terminals consents to acceptance
of said particular command, accepting said particular command.
5. A radio communication apparatus for a radio LAN (Local Area Network) system
that includes a plurality of terminals and at least one base apparatus wherein
a command issued from any of said terminals is received by said base apparatus
and information is transmitted from said base apparatus to the terminals by radio
communication between the terminals and said base apparatus, said base apparatus comprising:
reception means for receiving commands issued from any of said terminals, said
commands comprising both competitive commands and non-competitive commands;
discrimination means for determining whether the received command is a competitive
command whose acceptance can result in a disturbance of reception of data of any
other of said terminals, and further determining, based on a result of the determination
whether the received command is the competitive command, and whether or not the
command should be accepted; and
first transmission means for issuing, when said discrimination means determines
that acceptance of the command should be rejected, a notification of the rejection
of acceptance of the command to the terminal which has issued the command;
whereby the disturbance caused by an acceptance of a competitive command to other
terminals that are under a receiving state is minimized.
6. The radio communication apparatus according to claim 5, further comprising:
means for setting a priority order among said plurality of terminals;
means for determining whether said priority order of said terminal issuing said
command is higher than that of any other of said terminals currently receiving
data if it is determined that said received command is a competitive command;
means for accepting said command if it is determined that said priority order
of said terminal issuing said command is higher than that of any other of said
terminals currently receiving data; and
second transmission means for issuing a notification of said acceptance of said
command to said other terminals currently receiving data.
7. The radio communication apparatus according to claim 5, further comprising:
means for setting a predetermined time interval;
means for determining whether said predetermined time interval has elapsed since
the issuance of a command implementing a procedure currently in process if it is
determined that said received command is a competitive command;
means for accepting said command if it is determined that said predetermined
time interval has elapsed; and
second transmission means for issuing a notification of said acceptance of said
command to said other terminals currently receiving data.
8. The radio communication apparatus according to claim 5, further comprising:
means inquiring of said other terminals receiving data whether a particular command
may be accepted; and
means for accepting said particular command if a response to said inquiry from
all of said other terminals consents to acceptance of said particular command.
Description
BACKGROUND OF THE INVENTION
This invention relates generally to a command processing method for a radio
LAN (Local Area Network) system, and a radio communication apparatus which composes
a radio LAN system.
In order to view an audio/video program, access the Internet, or perform various
other desired functions with a computer it is conventionally necessary to maintain
at least one hard-wired connection so that desired data may be transferred from
any number of remote sites to the computer for processing, and then to an associated
display device for display. It would therefore be beneficial to provide an improved
device allowing for access to the above functions without maintaining such a hard-wired connection.
SUMMARY OF THE INVENTION
Therefore, generally speaking, in accordance with the invention, an improved
display terminal for a radio LAN system is provided.
In accordance with the invention, it has been proposed to construct a radio LAN
system from a plurality of apparatus and transmit and receive data between the
apparatus in a limited area such as within a house or within a room. To this end,
the IEEE (Institute of Electrical and Electronics Engineers) 802.11 standards prescribe
a 2.4 GHz and 5 GHz radio frequency bands that can be used for such a radio LAN system.
A radio LAN system of the type described includes, for example, a base apparatus
and one or more terminals. The base apparatus includes a built-in tuner or a tuner
connected thereto for receiving a broadcast and to which a telephone circuit or
the like is connected. A terminal that communicates with the base apparatus by
radio communication to send a command or other information to the base apparatus
and receive information such as image data and audio data from the base apparatus
to allow for the display of an image on a display section and the output sound
from a speaker or an earphone is also provided. Thus, a user of such a radio LAN
system can enjoy a ground wave TV (television) broadcast or a BS/CS (broadcasting
satellite/communications satellite) digital broadcast, access the Internet, or
enjoy telephone conversation using the display terminal regardless of the location
of the user in a house or in a room.
In particular, a radio LAN system can be configured as is shown in FIG. 1. The
radio LAN system shown in FIG. 1 includes two terminals 30A and 30B
each including an antenna 31, a liquid crystal display (LCD) apparatus 32,
a speaker 33 and a microphone 34. A base apparatus 10 is also
shown, and includes an antenna 11 for radio communication with terminals
30A and 30B and a built-in TV tuner 13 connected to an antenna
12 for reception of a TV broadcast. A telephone circuit 1 is also
connected to base unit 10. In accordance with the radio LAN system of the
invention, a user can use terminal 30A in a first location while another
user can use terminal 30B in a second location to enjoy a TV broadcast,
access the Internet or enjoy telephone conversation.
In the radio LAN system in accordance with the invention including two terminals
30A and 30B, for example, when a TV broadcast is to be enjoyed by
a user, if only one of the terminals is in use and receives the broadcast, then
the user can freely change the channel. However, when both of terminals 30A
and 30B are in use and receive the broadcast simultaneously, a problem arises
with regard to channel selection.
If the system is configured such that the channel to be received by the TV tuner
13 in base apparatus 10 is changed by base apparatus 10 each
time a channel changing command is issued from one of the terminals, then each
time a channel changing command is issued from any of the terminals, the broadcast
channel to be received by the terminals 30A and 30B is changed for
both terminals. As a result, confusion or conflict in channel selection occurs
between the user of terminal 30A and the user of terminal 30B.
While terminals 30A and 30B receive the same broadcast channel
X simultaneously, if a command for changing the channel to a channel Y is issued
from terminal 30A and another command for changing the channel to a channel
Z is issued immediately or substantially simultaneously from terminal 30B,
then the channel is changed to channel Z (the second requested channel) on both
of terminals 30A and 30B. Consequently, the user of the terminal
30A who has requested the channel selection to channel Y may assume that
the system has failed.
In accordance with the invention, an improved command processing method and radio
communication apparatus for a radio LAN system is provided composed of a plurality
of terminals and at least one base apparatus which prevents users of the terminals
from suffering confusion or conflict between them when issuing command from the terminals.
According to an aspect of the present invention, there is provided a method
for processing commands for a radio LAN system that includes a plurality of terminals
and at least one base apparatus. In the system, commands issued from any of the
terminals are received by the base apparatus. Information is transmitted from the
base apparatus to the terminals by radio communication. The base apparatus first
receives a command issued from any of the terminals. The base apparatus then determines
whether or not the received command is a competitive command whose acceptance may
result in the disturbance of any other terminal that is receiving information.
If it is determined that the received command is a competitive command, the command
is rejected. A notification of the rejection to the terminal which has transmitted
the command is issued.
The command processing method includes an alternative embodiment including the
feature that a priority order among the terminals may be set. Thus, even if a received
command is a competitive command, if the priority of the terminal which has transmitted
the command is higher than that of any of the other terminals that is currently
receiving information, then the base apparatus accepts the command and issues a
notification of the acceptance of the command to the other terminal or terminals.
In another alternative embodiment, a command processing method may be constructed
such that, even if a competitive command is received, if a predetermined time or
more has elapsed after implementation of a previous command regarding a process
being currently executed by any other terminal, then the base apparatus accepts
the command and issues a notification of the acceptance of the command to the other
terminals that are a receiving state.
In accordance with another alternative embodiment of the invention, a command
processing method may be constructed such that, if a competitive command is received,
then the base apparatus issues to the other terminals that are receiving information
an inquiry whether the command may be accepted. If a reply from the other terminals
accepts the command, the command is then accepted by the base unit.
According to another aspect of the invention, a radio communication apparatus
for a radio LAN system is provided that includes a plurality of terminals and at
least one base apparatus. A command issued from any of the terminals is received
by the base apparatus and information is transmitted from the base apparatus to
the terminals by radio communication. The radio communication apparatus is located
in the base apparatus. The radio communication apparatus comprises a receiver for
receiving a command issued from any of the terminals, and a discriminator for determining,
when a command issued from any of the terminals is received by the reception means,
whether the command is a competitive command whose acceptance may result in disturbance
of the reception of information by any other of the terminals. Based upon a result
of the determination, it is determined whether or not the command should be accepted.
Finally, when it is determined that acceptance of the command should be rejected,
a notification of the rejection of the command is transmitted to the terminal which
transmitted the command.
In the command processing method and the radio communication apparatus in accordance
with the invention, if a competitive command is issued from a terminal, it is generally
not accepted by the base apparatus. Therefore no disturbance or conflict occurs
among the users of the terminals in regard to handling of a command issued from
one of the terminals. If the command is not accepted, then a notification of such
a rejection is issued from the base apparatus to the terminal which originally
transmitted the command. Therefore, if the command is not accepted, the user of
the terminal which has issued the command does not think that the system has failed.
Still other objects and advantages of the invention will in part be obvious
and will in part be apparent from the specification and the drawings
The invention accordingly comprises the several steps and the relation of one
or more of such steps with respect to each of the others, and the apparatus embodying
features of construction, combination(s) of elements and arrangement of parts that
are adapted to effect such steps, all as exemplified in the following detailed
disclosure, and the scope of the invention will be indicated in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view showing an example of radio LAN system;
FIG. 2 is a schematic view showing an example of a radio LAN system to which
a command processing method according to an embodiment of the invention is applied;
FIG. 3 is a block diagram showing an example of functional block configuration
of a base apparatus of the radio LAN system of FIG. 2;
FIG. 4 is a block diagram showing an example of functional block configuration
of terminals of the radio LAN system of FIG. 2; and
FIGS. 5 to 7 are flow charts illustrating different forms of a command processing
method according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 2 shows an example of radio LAN system to which a command processing method
according to the present invention can be applied. Referring to FIG. 2, the radio
LAN system shown includes a base apparatus
10 and two display terminals
30A and
30B.
A telephone circuit
1 is connected to base apparatus
10. Base apparatus
10 includes an antenna
11 for radio communication with display terminals
30A and
30B so that display terminals
30A and
30B are
able to perform telephone communication as desired utilizing radio communication
with base apparatus
10 (as will be described below) and access the Internet.
Of course, any manner for accessing the Internet may be employed by display terminals
30A and
30B, as long as this method of access is properly connected
to base unit
10.
Further, an antenna
12 for receiving a ground wave television broadcast
and another antenna
14 for receiving a BS/CS digital broadcast are connected
to the base apparatus
10. A tuner
13 and a BS/CS tuner
15
are built into base apparatus
10 so that display terminals
30A and
30B can receive video and audio information of a ground wave television
broadcast and a BS/CS digital through radio communication with base apparatus
10.
Of course, rather than an antenna, a cable feed wire or other transmission media
for a television broadcast may be coupled with base apparatus
10. In accordance
with such a configuration, tuners
13 and
15 would be configured to
allow a user to select from among various audio/video programs provided via the
provided transmission media.
Furthermore, a playback apparatus such as a DVD player may be connected
as an external apparatus
50 so that the display terminals
30A and
30B can receive audio/video program information and so forth played back
by external apparatus
50 through radio communication with base apparatus
10. While a DVD player is shown, any appropriate playback device may be employed.
A remote controller transmitter
29 such as a remote controller mouse or
the like is connected to base apparatus
10. An infrared remote control signal
transmitted from remote controller transmitter
29 is received by a remote
control signal reception section
51 provided on external apparatus
50
to control external apparatus
50. Of course other control devices, such
as a radio wave remote control, or hardwired controller may be provided for allowing
control of external apparatus
50.
Display terminals
30A and
30B (collectively "display terminal
30") will now be described. Display terminal
30 includes an antenna
31 for radio communication with base apparatus
10, a liquid crystal
display (LCD) apparatus
32 for displaying an image, a speaker
33
for outputting sound, and a microphone
34 for inputting sound. Display terminal
30 further includes a key selection and operation section
35 including
a power supply key, an Internet key, an electronic mail key, a channel selection
key, a sound volume adjustment key and the like.
Further, a touch panel
36 is provided on a screen of LCD apparatus
32 so that, when a user touches touch panel
36 within a predetermined
region, a control panel
37 is displayed on LCD apparatus
32. A user
can touch a key switch section of control panel
37 to control various functions
of base apparatus
10, such as requesting a channel change.
Base apparatus
10 is functionally configured as shown in FIG. 3 while
display terminal
30 is functionally configured as shown in FIG. 4, as will
now be described.
Referring next to FIG. 3, base apparatus
10 includes a key operation
section
16 and a display section
17 which function as a user interface
between the user and base apparatus
10. Key operation section
16
is connected to a main control section
21 through an interface section
18.
Display section
17 is connected to main control section
21 through
a display control section
19. Remote controller transmitter
29 is
connected to main control section
21 through an interface section
28.
A signal of a ground wave television broadcast selected and demodulated, and
then
converted into digital image data by tuner
13 from a data signal received
by antenna
12, and is then sent to a compression-decompression section
24.
A signal of a BS/CS digital broadcast is selected and separated into compressed
image data and compressed audio data. The separated data are then decompressed
by BS/CS tuner
15, and are sent to compression-decompression section
24.
Telephone circuit
1 is connected to compression-decompression section
24
through a circuit interface section
25 and is also connected to a signal
control section
23 through a modem section
26.
Furthermore, external apparatus
50 reproduces and outputs data
to compression-decompression section
24, via external input interface
52.
Compression-decompression section
24 compresses
video data and audio data from TV tuner
13, BS/CS tuner
15, external
input interface
52 and circuit interface section
25 in accordance
with a predetermined compression system such as, for example, the MPEG (Moving
Picture Experts Group) system. The compressed video data and audio data are forwarded
to signal control section
23.
Further, compression-decompression section
24 decompresses compressed
audio data transmitted thereto from display terminal
30. This compressed
audio data is received by a radio communication section
22 and then forwarded
from radio communication section
22 to compression-decompression section
24 through signal control section
23. The decompressed audio signal
data is then forwarded to circuit interface section
25.
Radio communication section
22 modulates data forwarded from signal
control section
23 in accordance with a predetermined modulation system
such as, for example, the CCK (Complementary Code Keying) system or the OFDM (Orthogonal
Frequency Division Multiplexing) system, for example. The modulated data is then
converted into a high frequency signal in the 2.4 GHz band or the 5 GHz band. The
high frequency signal is then transmitted from antenna
11 to display terminal
30. Radio communication section
22 also converts a high frequency
signal transmitted thereto from display terminal
30 and received by antenna
11 into an intermediate frequency signal, demodulates the intermediate frequency
signal and forwards the demodulated data to signal control section
23.
Signal control section
23 arbitrates and selectively forwards video
data and audio data compressed by compression-decompression section
24,
data received by modem section
26 and control data from main control section
21 to radio communication section
22. Further, signal control section
23 selectively forwards data transmitted from display terminal
30
and received by radio communication section
22. This received data is then
forwarded from radio communication section
22 to signal control section
23, and from signal control section
23 to main control section
21,
modem section
26 and compression-decompression section
24.
Main control section
21 controls the components of base apparatus
10.
Main control section
21 comprises, though not shown in FIG. 3, a CPU (Central
Processing Unit), a ROM (Read Only Memory) in which programs to be executed by
the CPU, fixed data and so forth are written, a RAM (Random Access Memory) which
functions as a working area of the CPU and other necessary elements.
Referring next to FIG. 4, display terminal
30 constructed in accordance
with the invention includes a main control section
41 to which key operation
section
35 is connected through an interface section
38. Further,
a coordinate detection section
39 is provided as an interface for touch
panel
36 and detects coordinates of a touched position of touch panel
36.
The detected coordinate values are forwarded to main control section
41.
If touch panel
36 is touched in the predetermined region thereof, then
main control section
41 controls a display control section
45 to
display control panel
37 on LCD apparatus
32. Then, if the key switch
section of control panel
37 displayed on the LCD apparatus
32 is
touched, main control section
41 produces control data in response to the
touched position of the key switch section. Further, if key operation section
35
is operated, main control section
41 produces control data in response to
the operated key. The control data produced by main control section
41 is
forwarded to a signal control section
43.
In display terminal
30, an audio signal from microphone
34 is amplified
by an audio amplifier
48 and converted into digital audio data by an A/D
(analog to digital) converter
49. The audio data is compressed in accordance
with a predetermined compression system by a compression-decompression section
44. The compressed audio data is then forwarded to signal control section
43.
Signal control section
43 arbitrates and selectively forwards control
data from main control section
41 and audio data compressed by compression-decompression
section
44 to a radio communication section
42. Further, signal control
section
43 selectively forwards data transmitted from base apparatus
10
and received by radio communication section
42. Control and other data that
are previously received by modem section
26 of base apparatus
10
are forwarded to main control section
41, while compressed video data and
audio data are forwarded to compression-decompression section
44.
Radio communication section
42 modulates data forwarded from signal
control section
43 in accordance with a predetermined modulation system,
converts the modulated data into a high frequency signal in the 2.4 GHz band or
the 5 GHz band and transmits the high frequency signal from antenna
31 to
base apparatus
10. Further, radio communication section
42 converts
a high frequency signal transmitted from base apparatus
10 and received
by antenna
31 into an intermediate frequency signal, demodulates the intermediate
frequency signal and forwards the demodulated data to signal control section
43.
Compression-decompression section
44 decompresses
compressed video data and audio data forwarded from signal control section
43.
The decompressed video data is displayed as an image on LCD apparatus
32
under the control of display control section
45. The decompressed audio
data is converted into an analog audio signal by a D/A (digital to analog) converter
46, is amplified by an audio amplifier
47 and is output as sound
from speaker
33.
Main control section
41 controls the components of display terminal
30
and includes, though not shown in FIG. 4, a CPU, a ROM, a RAM and so forth similarly
to main control section
21 of base apparatus
10.
In order to receive a ground wave television broadcast or a BS/CS digital broadcast
at display terminal
30 in the radio LAN system described above, video data
and audio data from TV tuner
13 or BS/CS tuner
15 of base unit
10
from a selected channel are first compressed by compression-decompression section
24. This compressed data is then transmitted by radio communication section
22 under the control of signal control section
23 to display terminal
30. In display terminal
30, the compressed video data and audio data
are first received by radio communication section
42. This received data
is then forwarded to and decompressed by compression-decompression section
44
under the control of signal control section
43. Consequently, an image is
displayed on LCD apparatus
32 and sound is output from speaker
33.
If a user selects a channel of a TV or BS/CS broadcast using key operation section
35 or control panel
37, a command indicating the desired channel
is transmitted from main control section
41 of display terminal
30
to the base apparatus
10 by radio communication section
42 under
the control of signal control section
43.
In base apparatus
10, the transmitted command is received by radio communication
section
22 and sent to main control section
21 under the control
of signal control section
23. Main control section
21 controls tuner
13 to select a channel in accordance with the received command.
In order to view and hear data played back by external apparatus
50, the
user initiates a playback operation through key operation section
35 or
control panel
37. In response, a command is transmitted from terminal
30
to base apparatus
10 requesting playback of data by external apparatus
50.
External apparatus
50 is controlled in accordance with a command
transmitted by remote controller
29. Desired image and audio data are therefore
played back by external apparatus
50. Image and audio data output from external
apparatus
50 are transmitted from base apparatus
10 to terminal
30
in a manner similar to that noted above. At terminal
30 an image is displayed
on LCD
32 and sound is output from speaker
33 in accordance with
the received image data and audio data, respectively.
In order to access the Internet, a user operates key operation section
35
or control panel
37 to request connection to an ISP (Internet Service Provider).
The request is transmitted from main control section
41 of display terminal
30 to base apparatus
10 by radio communication section
42
under the control of signal control section
43.
In base apparatus
10, a request is received by radio communication section
22 and is forwarded to main control section
21 under the control
of signal control section
23. Consequently, modem section
26 and
circuit interface section
25 are controlled in response to the request by
main control section
21 to establish a connection to the ISP. Then, for
example, data sent from the ISP to telephone circuit
1 in response to the
access request to a certain homepage is sent to signal control section
23
through circuit interface section
25 and the modem section
26. This
data is in turn transmitted to display terminal
30 by radio communication
section
22.
In display terminal
30, the data is received by the radio communication
section
42 and sent to main control section
41 under the control
of signal control section
43. Main control section
41 processes the
data to produce display data. This display data is then forwarded to display control
section
45 so that the retrieved homepage is displayed on the LCD apparatus
32. Of course, access to the Internet may be performed employing any other
type of provided ISP connection, including but not limited to cable transmissions,
satellite transmissions, DSL transmissions, or any other information data transmission medium.
In order to perform the function of allowing for a telephone conversation, a
transmission
audio signal from microphone
34 of display terminal
30 is converted
into digital audio data by A/D converter
49 and compressed by compression-decompression
section
44. Then, the compressed audio data is transmitted to base apparatus
10 by radio communication section
42 under the control of the signal
control section
43.
In base apparatus
10, the compressed audio data is received by radio communication
section
22. This received data is in turn forwarded to and decompressed
by compression-decompression section
24 under the control of signal control
section
23. Then, the decompressed transmission audio signal is forwarded
to telephone circuit
1 through circuit interface section
25.
Meanwhile, a received audio signal transmitted over telephone circuit
1 is sent through circuit interface section
25 to compression-decompression
section
24 where it is compressed. The compressed audio data is transmitted
to display terminal
30 by radio communication section
22 under the
control of signal control section
23.
In display terminal
30, the compressed audio data is received by radio
communication section
42. This received audio data is forwarded to and decompressed
by compression-decompression section
44 under the control of signal control
section
43. Then, the decompressed audio data is converted into an analog
audio signal by D/A converter
46 and output as a voice from speaker
33.
Different forms of command processing methods according to the invention
will now be described. A command issued from the terminal
30A or
30B
is processed by the base apparatus
10 in the radio LAN system described hereinabove.
According to the command processing method of the present invention, if
a command issued from terminal
30A or
30B is a competitive command,
then the base apparatus
10 does not accept the command. A competitive command
is one that would disturb the reception of information by another terminal from
the base apparatus. For example, if a channel selection command is issued from
terminal
30A while the power supply to terminal
30B is off and terminal
30B is not in receiving information, then the command is not a competitive
command. On the other hand, if a channel changing command is issued from terminal
30A while terminals
30A and
30B are receiving the same channel
from the base apparatus, then the command is a competitive command.
In the command processing method of the invention, when a command is a competitive
command and therefore is not accepted, base apparatus
10 issues a notification
to the terminal from which the command has been transmitted indicating that the
command could not be accepted. In the terminal receiving the notification, a message
such as "This command cannot be accepted." is displayed on LCD
32 or is
output from speaker
33 under the control of main control section
41.
Identification information (ID) for identification of the terminal
which transmits a command is added to the command transmitted from terminal
30A
or
30B to base apparatus
10. Also, ID for identification of the terminal
of the destination of a response to command is added to a notification transmitted
from base apparatus
10 to terminal
30A or
30B.
Several detailed examples of the command processing method according to the
present invention will now be described.
Referring next to FIG. 5, a priority order is determined between terminals
30A and
30B. In other words, priority is given to one of terminals
30A and
30B.
However, the priority need not necessarily be given permanently to one of
the terminals. For example, priority may be given to terminal
30A or
30B
depending upon a current time. Thus, priority may be given to terminal
30A
from 6:00 a.m. to 6:00 p.m. but to terminal
30B from 6:00 p.m. to 6:00 a.m.
Priority may also be determined based upon the day of the week such that priority
is given to terminal
30A from Monday to Friday but to terminal
30B
on Saturday and Sunday. The desired priority order is set by the user in main control
section
21 of base apparatus
10 through key operation section
16
of base apparatus
10.
In the first example in accordance with the invention, main control section
21
of base apparatus
10 executes a command processing routine
60 as
illustrated in FIG. 5. In accordance with command processing routine
60,
even if a received command is a competitive command, if the terminal which has
issued the command has priority, then the command is accepted and a notification
of the acceptance of the command is sent to the other receiving terminals.
In particular, referring to FIG. 5, a command is received by base apparatus
10
from one of the terminals. At step
61 it is determined whether the command
is a competitive command. If it is determined that the command is not a competitive
command, then processing advances from step
61 to step
62, in which
main control section
21 of base apparatus
10 accepts the command.
Accordingly, if no other terminal is receiving information, then the user of the
terminal can change the channel freely irrespective of whether or not the user
has the priority.
However, if it is determined in step
61 that the received command
is a competitive command, then the processing advances from step
61 to step
63. At step
63 main control section
21 determines whether
the terminal that has issued the command has priority. If it is determined that
the terminal issuing the command does not have the priority, then processing advances
from step
63 to step
64. At step
64 main control section
21
of base apparatus
10 rejects the command and issues a notification of the
rejection of the command request to the terminal that issued the command. Accordingly,
if a channel changing command is issued from terminal
30A while terminals
30A and
30B are simultaneously receiving the same channel, if terminal
30A does not have priority, then the channel changing command from terminal
30A is not accepted.
If it is determined in step
63 that the terminal that issued the command
has priority, then processing advances from step
63 to step
65. At
step
65 main control section
21 of base apparatus
10 accepts
the command and notifies the other terminal of this acceptance. Thereafter, processing
advances to step S
66, in which base apparatus
10 performs the process
requested in the command. Accordingly, if a channel changing command is issued
from the terminal
30A while the terminals
30A and
30B are
simultaneously receiving the same channel, then if terminal
30A has priority,
the channel changing command from the terminal
30A is accepted. Because
terminal
30B is notified in advance that the channel will be changed, the
user of terminal
30B is aware of the change.
Where the priority is given to terminal
30A or
30B depending
upon time or day of the week as described above, it is therefore determined in
step
63 whether or not the terminal which has issued the command has priority
at the present time or day of the week. Where the priority is given to the terminal
30A or
30B depending upon time or day of the week as described above,
control by terminal
30A and terminal
30B can be adjusted appropriately.
Referring next to FIG. 6, main control section
21 of base apparatus
10 executes such a command processing routine
70. In accordance with
processing routine
70 if a received command is a competitive command, and
the desired command is issued after a predetermined time or more after a beginning
of a process being currently executed by the other terminal, then the command is
accepted and the other terminal is notified. Preferably, the predetermined time
represents around one to two hours.
In particular, when base apparatus
10 receives a command from one of the
terminals, at step
71, main control section
21 first determines whether
the command is a competitive command. If it is determined that the command is not
a competitive command, then processing advances from step
71 to step
72.
At step
72, main control section
21 of base apparatus
10 accepts
the command. Then, processing further advances to step
73, in which main
control section
21 resets a timer to update time measurement. Accordingly,
when only one terminal is in a receiving state, the user of the terminal can change
the channel freely. Each time the channel is changed, the timer is reset.
If it is determined at in step
71 that the command is a competitive command,
then processing advances from step
71 to step
74. At step
74
main control section
21 of base apparatus
10 determines from the
timer whether or not a predetermined time or more has elapsed after the acceptance
of a prior command initiating the process being currently executed by the other
terminal. If the predetermined time or more has not elapsed, then processing advances
from step
74 to step
75. At step
75 main control section
21
of base apparatus
10 rejects the requested command and notifies the terminal
which has issued the command of the rejection. Accordingly, when a terminal is
receiving a certain channel, if the user of another terminal tries to select a
channel different from the channel being received by the first terminal, if at
least a predetermined time period has not elapsed after the acceptance of a preceding
command that selected the certain channel the channel selection command from the
other terminal is not accepted.
If base apparatus
10 determines in step
74 that at least a predetermined
time has elapsed, then processing advances from step
74 to step
76.
At step
76 main control section
21 of base apparatus
10 notifies
the other terminal currently receiving data that the newly requested command will
be accepted. Then, processing advances to step
77, in which main control
section
21 of base apparatus
10 performs a process requested by the
command. Further, in a step
78, main control section
21 resets the
timer to update the time measurement. Accordingly, in the case described above,
if a fixed predetermined time or more has elapsed after the acceptance of a preceding
command initiating a present activity from one terminal, then channel selection
command received from another terminal is accepted. The user of the one terminal
is therefore notified in advance that the channel will be changed.
Referring next to FIG. 7, main control section
21 of base apparatus
10 executes a command processing routine
80. In accordance with this
embodiment of the invention, even if a competitive command is received, if the
user of the other terminal which is receiving data consents to acceptance of the
command, then the command is accepted.
In command processing routine
80, base apparatus
10 first determines
in step
81 whether or not a received command is a competitive command. If
the command is not a competitive command, then processing advances from step
81
to step
82. At step
82, main control section
21 of base apparatus
10 accepts the command.
If it is determined in step
81 that the command is a competitive command,
then processing advances from step
81 to step
83. At step
83
main control section
21 of base apparatus
10 issues to the other
terminal currently receiving data an inquiry whether or not the command may be
accepted. The inquiry is performed by transmitting control data from base apparatus
10 to the other terminal and displaying a message such as "May the channel
be changed?" on the LCD
32, or outputting from speaker
33 on the
other terminal an audio version of the question.
In response to the inquiry, the user of the other terminal operates key operation
section
35 or control panel
37 to issue a reply representing whether
or not the command may be accepted. Reply data is transmitted from the other terminal
to the base apparatus
10.
After the inquiry in step
83, processing advances to step
84.
At step
84 main control section
21 of base apparatus
10 determines
whether or not the received reply accepts the command. If the reply objects to
the acceptance of the command, then processing advances from step
84 to
step
85. At step
85 main control section
21 of base apparatus
10 rejects the command and notifies the terminal that issued the command
of the rejection.
If the reply consents to the acceptance of the command, then processing advances
from step
84 to step
86. At step
86 main control section
21
of the base apparatus
10 accepts the command and implements the requested action.
While the radio LAN system described hereinabove includes the single base apparatus
10 and the two terminals
30A and
30B, the present invention
can be applied also to a radio LAN system which includes a single base apparatus
and three or more terminals.
In this instance, where a priority order is set among the terminals as in the
first example described hereinabove, it is possible to give priority permanently
to one or more of the terminals, to permanently give different order numbers to
the terminals, to give priority to one or more of the terminals depending upon
the time or day of the week, or to give different priority order numbers to the terminals.
In this case with three or more terminals, base apparatus
10 determines,
at step
63 of command processing routine
60 of FIG. 5, whether or
not the priority of the terminal which has issued a command is higher than the
priority of the other terminal or terminals that are currently receiving data.
If the priority is not higher or is equal, then the command is not accepted. If
the priority is higher, then the command is accepted.
Further, where the command is accepted when the user of the other terminal
consents to acceptance of the command, if a plurality of other terminals are also
receiving data, then the base apparatus
10 accepts the command, in step
84 of the command processing routine
80 of FIG. 7, only when the
command is accepted by a majority of the plurality of terminals currently receiv
