Estimation of interference variation caused by the addition or deletion of a connection

1. A method for determining whether a connection event between a base station and a wireless transmit/receive unit (WTRU) should be accepted or rejected, the method comprising:

measuring the interference level I 0 in a candidate timeslot;

measuring the path loss L between the base station and the WTRU;

measuring the total transmit power P 0 of the base station;

determining a thermal noise level θ;

determining a fading average signal-to-interference ratio (SIR);

obtaining a value G c , which relates to the link gain between the base station and a WTRU operating in an adjacent cell; and

calculating a ratio R, wherein if the ratio R is above a certain threshold the connection event will be accepted and if the ratio R is below the threshold the connection event will be rejected;

wherein the ratio R is calculated using the following equation:

R

=

1

1

-

(

I

0

θ

-

1

)

⁢

L

⁢

⁢

SIR

(

P

0

I

0

)

+

1

G

c

.

2. The method of claim 1 wherein the connection even is a connection addition.

3. The method of claim 2 wherein the threshold is zero.

4. A method for determining whether a connection event between a base station and a wireless transmit/receive unit (WTRU) should be accepted or rejected, the method comprising:

measuring the interference level I 0 in a candidate time slot;

determining the transmission power P c of an existing connection that is similar to the connection event;

measuring the total transmit power P 0 of the base station;

determining a thermal noise level θ; obtaining a value G c , which relates to the link gain between a base station and a WTRU operating in an adjacent cell; and

calculating a ratio R, wherein if the ratio R is above a certain threshold the connection event will be accepted and if the ratio R is below the threshold the connection event will be rejected;

wherein the ratio R is calculated using the following equation:

R

=

1

1

+

(

I

0

θ

-

1

)

⁢

L

⁢

⁢

SIR

(

P

0

I

0

)

+

1

G

c

.

5. The method of claim 4 , wherein the connection event is a connection addition.

6. The method of claim 5 wherein the threshold is zero.

7. A method for estimating interference variation caused by a connection event between a base station and a wireless transmit/receive unit (WTRU), the method comprising:

obtaining signal parameters for a communications link with a WTRU;

computing a plurality of variation parameters from the signal parameters;

computing an intermediary variable based on the computed variation parameters;

in the case of an addition connection event, using the intermediary variable to compute a ratio of predicted interference and interference without the connection event resulting from the addition;

determining if the ratio exceeds a predetermined maximum value, and if the interference exceeds the predetermined maximum value deeming the interference excessive; and

in the case of the interference value not exceeding the predetermined maximum value level, computing a predicted interference change as a result of the connection event.

8. The method of claim 7 , further comprising:

in the case of a deletion connection event, using the intermediary variable to compute the ratio resulting from the deletion; and

computing the predicted interference change as a result of the connection event.

9. The method of claim 7 , further comprising:

calculating, as one of the variation parameters, an interference variation parameter based on a ratio of an interference level as one of the signal parameters and a thermal noise level; and

determining whether the interference variation parameter falls below a reference value, and if the interference variation parameter falls below the reference value, setting the interference variation parameter at the reference value.

10. The method of claim 7 , further comprising:

calculating, as one of the variation parameters, an interference variation parameter based on an interference level I 0 as one of the signal parameters and a thermal noise level Θ as s=(I 0 /Θ)−1; and

determining whether the interference variation parameter falls below a reference value, and if the interference variation parameter falls below the reference value, setting the interference variation parameter at the reference value.

11. The method of claim 8 , wherein the signal parameters obtained include thermal noise level (θ), interference level (I 0 ), signal-to-interference ratio (SIR), and at least one parameter related to the system deployment.

12. A method for determining whether a connection event between a base station and a wireless transmit/receive unit (WTRU) should be accepted or rejected, the method comprising:

measuring the interference level I 0 in a candidate timeslot;

measuring the path loss L between the base station and the WTRU;

measuring the total transmit power P 0 of the base station;

determining a thermal noise level θ;

determining a fading average signal-to-interference ratio (SIR);

obtaining a value G c , which relates to the link gain between the base station and a WTRU operating in an adjacent cell; and

calculating a ratio R, wherein if the ratio R is above a certain threshold the connection event will be accepted and if the ratio R is below the threshold the connection event will be rejected:

wherein the ratio R is calculated using the following equation:

R

=

1

1

-

(

I

0

θ

-

1

)

⁢

P

c

I

0

(

P

0

I

0

)

+

1

G

c

.

13. The method of claim 12 wherein the connection event is a connection deletion.

14. The method of claim 13 wherein the threshold is zero.

15. A method for determining whether a connection event between a base station and a wireless transmit/receive unit (WTRU) should be accepted or rejected, the method comprising:

measuring the interference level I 0 in a candidate timeslot;

determining the transmission power P c of an existing connection that is similar to the connection event;

measuring the total transmit power P 0 of the base station;

determining a thermal noise level θ;

obtaining a value G c , which relates to the link gain between a base station and a WTRU operating in an adjacent cell; and

calculating a ratio R, wherein if the ratio R is above a certain threshold the connection event will be accepted and if the ratio R is below the threshold the connection event will be rejected;

wherein the ratio R is calculated using the following equation:

R

=

1

1

+

(

I

0

θ

-

1

)

⁢

P

c

I

0

(

P

0

I

0

)

+

1

G

c

.

16. The method of claim 15 wherein the connection even is a connection deletion.

17. The method of claim 16 wherein the threshold is zero.