Method and apparatus for providing multicast services in a wireless communication environment
View Patent ↗Method for multicasting messages to users of a wireless communication system includes the steps of establishing a power ratio threshold for transmitting the messages, measuring respective power ratios of the users, comparing the established power ratio threshold to the measured power ratios, determining a first subset of the users and a second subset of the users based upon the measured power ratios and delivering the messages to the first subset of the plurality of users via a first transmission scheme. The first transmission scheme delivers the messages to all of the users of the first subset via a broadcast channel. The method also has a step of delivering the messages to the second subset of the users via a second transmission scheme. The second transmission scheme delivers the messages to each of the users of the second subset via respective dedicated channels.
1. Method for multicasting a message to a plurality of users comprising:
establishing a power ratio threshold adapted to enable reliable transmission of said message;
comparing the established power ratio threshold to measured power ratios associated with said plurality of users;
determining a first subset of the plurality of users and a second subset of the plurality of users based upon the measured power ratios;
delivering said message to the first subset of the plurality of users via a first transmission scheme; and
delivering said message to the second subset of the plurality of users via a second transmission scheme.
2. The method of claim 1 , wherein:
said first transmission scheme delivering said message to said first user subset is via a broadcast channel.
3. The method of claim 1 , wherein:
said second transmission scheme delivering said message to said second user subset is via respective dedicated channels.
4. The method of claim 1 ,further comprising:
periodically measuring the respective power ratios of said plurality of users.
5. The method of claim 1 , further comprising:
continuously measuring the respective power ratios of said plurality of users.
6. The method of claim 1 , wherein the step of determining is performed by evaluating an equation of the following form:
(
N
-
m
)
=
arg
m
min
(
P
B
(
N
-
m
)
+
(
∑
i
=
1
m
P
i
)
)
where N is the plurality of users in a given area, N−m is the first subset of the plurality of users, m is the second subset of the plurality of users, P B (k) is a reliable MBMS broadcast service power level to user k, and Pi is the required power to support user i using a dedicated channel.
7. The method of claim 1 , wherein the first subset of users has power requirements different from the second subset of users.
8. A computer readable medium having stored thereon a program which, when executed, performs a method of multicasting a message to a plurality of users comprising:
establishing a power ratio threshold adapted to enable reliable transmission of said message;
comparing the established power ratio threshold to measured power ratios associated with said plurality of users;
determining a first subset of the plurality of users and a second subset of the plurality of users based upon the measured power ratios;
delivering said message to the first subset of the plurality of users via a first transmission scheme; and
delivering said message to the second subset of the plurality of users via a second transmission scheme.
9. The method of claim 8 , wherein: said first transmission scheme delivering said message to said first user subset is via a broadcast channel.
10. The method of claim 8 , wherein:
said second transmission scheme delivering said message to said second user subset is via respective dedicated channels.
11. The method of claim 8 , further comprising:
periodically measuring the respective power ratios of said plurality of users.
12. The method of claim 8 further comprising:
continuously measuring the respective power ratios of said plurality of users.
13. The method of claim 8 wherein the step of determining is performed by evaluating an equation of the following form:
(
N
-
m
)
=
arg
m
min
(
P
B
(
N
-
m
)
+
(
∑
i
=
1
m
P
i
)
)
where N is the plurality of users in a given area, N−m is the first subset of the plurality of users, m is the second subset of the plurality of users, P B (k) is a reliable MBMS broadcast service power level to user k, and Pi is the required power to support user i using a dedicated channel.