Method and system of setting transmitter power levels
The invention relates to a method and system of setting transmitter power levels, particularly in a Local Network Node transmitter, providing a pico cell for private use. A User Equipment (UE) is used to make measurements of the transmission link properties, such as downlink power and round trip time. Based on the measurements made at one or a plurality of locations, the power of the Local Network Node can be determined such that interference is minimized with any overlying cells of a macro-network. Call handovers between the UE and the cell of a macro network can also be arranged based on properties measure by the UE.
1. A network node for providing user equipment with a connection to a mobile network, the mobile network comprising one or more cells overlapping a coverage area of the network node, the network node comprising:
a processing system to perform operations comprising:
receiving, from the user equipment, one or more parameters related to interference on a downlink between the user equipment and the network node, the interference resulting at least partly from overlapping cells of the mobile network and other competing network nodes, the one or more parameters corresponding to a signal power at the user equipment for one or more of the overlapping cells and the other competing local network nodes; and
determining a transmit power for the downlink based on the one or more parameters.
2. The network node of claim 1 , wherein the processing system comprises a measuring processor to determine constants relating a radiation power of a transmitting antenna and a power received from the transmitting antenna.
3. The network node of claim 1 , wherein the transmit power is determined based on an expression:
P
Tx
=
E
b
N
o
1
PG
[
∑
i
=
1
m
a
i
I
oi
+
∑
j
=
1
n
b
j
I
oj
]
T
c
k
LNN
r
N
LNN
F
m
where P Tx is the transmit power, E b is a required energy per bit, N o is a noise power spectral density, PG is a processing gain, I oi is a measured received signal power at the user equipment from an overlapping cell, I oj is a measured received signal power at the user equipment from a competing network node, a and b are scaling factors, m and n are numbers of overlapping cells and competing network nodes respectively, T c is a chip duration, r is a distance of the user equipment from the network node, k and N are constants relating a path loss in the downlink to the distance, and F is a predetermined margin.
4. The network node of claim 1 , wherein the processing system comprises a controller to request the user equipment to obtain information related to a power of the downlink and to obtain the one or more parameters.
5. A method for use in determining a transmit power of a downlink between a network node and user equipment having a connection to a mobile network via the network node, the mobile network comprising one or more cells overlapping a coverage area of the network node, the method being performed by the user equipment and comprising:
obtaining one or more parameters related to interference on a downlink between the user equipment and the network node, the interference resulting at least partly from overlapping cells of the mobile network and other competing network nodes, the one or more parameters corresponding to a signal power at the user equipment for one or more of the overlapping cells and the other competing network nodes; and
transmitting the one or more parameters to the network node;
wherein the one or more parameters are usable by the network node in a process for determining a transmit power for the downlink.
6. The method of claim 5 , wherein the process for determining the transmit power for the downlink comprises:
determining, using information related to the power of the downlink, constants relating a radiation power of a transmitting antenna and a power received from the antenna.
7. The method of claim 5 , wherein the transmit power for the downlink is based on an expression:
P
Tx
=
E
b
N
o
1
PG
[
∑
i
=
1
m
a
i
I
oi
+
∑
j
=
1
n
b
j
I
oj
]
T
c
k
LNN
r
N
LNN
F
m
where P Tx is the transmit power, E b is a required energy per bit, N o is a noise power spectral density, PG is a processing gain, l oi is a measured received signal power at the user equipment from an overlapping cell, I oj is a measured received signal power at the user equipment from a competing network node, a and b are scaling factors, m and n are numbers of overlapping cells and competing network nodes respectively, T c is a chip duration, r is a distance of the user equipment from the network node, k and N are constants relating a path loss in the downlink to the distance, and F is a predetermined margin.
8. The method of claim 5 , further comprising;
receiving a message from the network node that instructs the user equipment to measure one or more parameters related to the power of the downlink; and
measuring the one or more parameters related to the interference.
9. A method performed by a network node for providing user equipment with a connection to a mobile network, the mobile network comprising one or more cells overlapping a coverage area of the network node, the method comprising:
receiving, from the user equipment, one or more parameters related to interference on a downlink between the user equipment and the network node, the interference resulting at least partly from overlapping cells of the mobile network and other competing network nodes, the one or more parameters corresponding to a signal power at the user equipment for one or more of the overlapping cells and the other competing local network nodes; and
determining a transmit power for the downlink based on the one or more parameters.
10. The method of claim 9 , wherein determining the transmit power comprises determining constants relating a radiation power of a transmitting antenna and a power received from the transmitting antenna.
11. The method node of claim 9 , wherein the transmit power is based on an expression:
P
Tx
=
E
b
N
o
1
PG
[
∑
i
=
1
m
a
i
I
oi
+
∑
j
=
1
n
b
j
I
oj
]
T
c
k
LNN
r
N
LNN
F
m
where P TX is the transmit power, E b is a required energy per bit, N o is a noise power spectral density, PG is a processing gain, I oi is a measured received signal power at the user equipment from an overlapping cell, I oj is a measured received signal power at the user equipment from a competing network node, a and b are scaling factors, m and n are numbers of overlapping cells and competing network nodes respectively, T c is a chip duration, r is a distance of the user equipment from the network node, k and N are constants relating a path loss in the downlink to the distance, and F is a predetermined margin.
12. The method of claim 9 , further comprising requesting that the user equipment measure one or more parameters related to a power of the downlink and the one or more parameters related to the interference.
13. User equipment configured for connection with a mobile network via a network node, the mobile network comprising one or more cells overlapping a coverage area of the network node, the user equipment comprising:
a processing device to perform operations comprising:
obtaining one or more parameters related to interference on a downlink between the user equipment and the network node, the interference resulting at least partly from overlapping cells of the mobile network and other competing network nodes, the one or more parameters corresponding to a signal power at the user equipment for one or more of the overlapping cells and the other competing network nodes; and
transmitting the one or more parameters to the network node;
wherein the one or more parameters are usable by the network node in a process for determining a transmit power for the downlink.
14. The user equipment of claim 13 , wherein the process for determining the transmit power for the downlink comprises:
determining, using information related to the power of the downlink, constants relating a radiation power of a transmitting antenna and a power received from the antenna.
15. The user equipment of claim 13 , wherein the transmit power for the downlink is based on an expression:
P
Tx
=
E
b
N
o
1
PG
[
∑
i
=
1
m
a
i
I
oi
+
∑
j
=
1
n
b
j
I
oj
]
T
c
k
LNN
r
N
LNN
F
m
where P TX is the transmit power, E b is a required energy per bit, N o is a noise power spectral density, PG is a processing gain, l oi is a measured received signal power at the user equipment from an overlapping cell, I oj is a measured received signal power at the user equipment from a competing network node, a and b are scaling factors, m and n are numbers of overlapping cells and competing network nodes respectively, T c is a chip duration, r is a distance of the user equipment from the network node, k and N are constants relating a path loss in the downlink to the distance, and F is a predetermined margin.
16. The user equipment of claim 13 , wherein the operations comprise:
receiving a message from the network node that instructs the user equipment to measure one or more parameters related to the power of the downlink; and
measuring the one or more parameters related to the interference.
17. A system for providing user equipment with a connection to a mobile network via a network node, the mobile network comprising one or more cells overlapping a coverage area of the network node, the system comprising:
the user equipment comprising processing circuitry to perform operations comprising:
obtaining one or more parameters related to interference on a downlink between the user equipment and the network node, the interference resulting at least partly from overlapping cells of the mobile network and other competing network nodes, the one or more parameters corresponding to a signal power at the user equipment for one or more of the overlapping cells and the other competing network nodes; and
transmitting the one or more parameters to the network node; and
the network node comprising processing circuitry to perform operations comprising:
receiving the one or more parameters from the user equipment; and
determining a transmit power for the downlink using the one or more parameters.
18. The system of claim 17 , wherein the processing circuitry of the network node is configured to perform operations comprising:
receiving one or more parameters related to the transmit power of the downlink between the user equipment and the local network node;
wherein determining the transmit power for the downlink is performed also using the one or more parameters related to the power of the downlink.
19. The system of claim 17 , wherein the processing circuitry of the network node comprises one or more processors.
20. The system of claim 19 , wherein the one or more processors comprise a first processor and a second processor.
21. The system of claim 17 , wherein the transmit power for the downlink is based on an expression:
P
Tx
=
E
b
N
o
1
PG
[
∑
i
=
1
m
a
i
I
oi
+
∑
j
=
1
n
b
j
I
oj
]
T
c
k
LNN
r
N
LNN
F
m
where P TX is the transmit power, E b is a required energy per bit, N o is a noise power spectral density, PG is a processing gain, l oi is a measured received signal power at the user equipment from an overlapping cell, I oj is a measured received signal power at the user equipment from a competing network node, a and b are scaling factors, m and n are numbers of overlapping cells and competing network nodes respectively, T c is a chip duration, r is a distance of the user equipment from the network node, k and N are constants relating a path loss in the downlink to the distance, and F is a predetermined margin.