Power control system for transmission chain in a transceiver

• US 8,615,209 B1
• Filed: 05/31/2011
• Issued: 12/24/2013
• Est. Priority Date: 09/01/2010
• Status: Active Grant

• Current Assignee: Qorvo US, Inc. (Qorvo, Inc.)
• Original Assignee: RF Micro Devices Incorporated (Qorvo, Inc.)
• Inventors: Khlat, Nadim
• Primary Examiner(s): Nguyen, Lee
• Application Number:
  US13/149,265
• Time in Patent Office: 938 Days
• Field of Search: 455/69, 455/126, 4551271-1273, 455/522, 370/342, 370/345, 370/347
• US Class Current: 455/127.1
• CPC Class Codes: H04B 1/0458 Arrangements for matching and coupling between power amplifier and antenna or between amplifying stages matching circuits in general H03H
• CPC Class Codes: H04B 1/18 Input circuits, e.g. for coupling to an antenna or a transmission line coupling networks between antennas or lines and receivers independent of the nature of the receiver H03H
• CPC Class Codes: H04B 2001/0416 having gain or transmission power control
• CPC Class Codes: H04W 52/30 using constraints in the total amount of available transmission power

Abstract

A transceiver is provided that has a power control system, which can internally control the current power level of a transmission signal within a physical uplink channel. The transceiver includes a transmitter circuit with a coupler, which generates a transmit feedback signal having a signal level associated with the current power level of the transmission signal. In this manner, the transceiver can internally detect the current power level of the transmission signal and accurately adjust the current power level based on transmission power control (TPC) information received from the base station.

Claims

1. A transceiver, comprising:

a transmitter circuit operable to up convert a first transmission signal into a first physical uplink channel, the transmitter circuit having;

a transmission amplification circuit having a first adjustable gain and a maximum power level that is providable by the first adjustable gain of the transmission amplification circuit, wherein the transmission amplification circuit is operable to amplify the first transmission signal in accordance with the first adjustable gain; and

a coupler connected to generate a transmit feedback signal having a signal level associated with a current power level of the first transmission signal;

an antenna tuner having an impedance response, wherein the antenna tuner is coupled to receive the first transmission signal from the transmission amplification circuit;

a receiver circuit operable to down convert a first receive signal out of a first physical downlink channel, wherein the first receive signal includes transmission power control information for adjusting the current power level of the first transmission signal to a first desired power level; and

a power control system operably associated with the transmitter circuit wherein the power control system is configured to;

adjust the first adjustable gain of the transmission amplification circuit based on the signal level of the transmit feedback signal and the transmission power control information so as to reduce a difference between the current power level of the first transmission signal and the first desired power level; and

adjust the impedance response of the antenna tuner to reduce the difference between the current power level of the first transmission signal and the first desired power level when the maximum power level that is providable by the first adjustable gain is reached by the transmission amplification circuit and when the first desired power level is above the maximum power level of the transmission amplification circuit.

2. The transceiver of claim 1, wherein the coupler comprises:

a first port coupled to receive the first transmission signal from the transmission amplification circuit;

a second port coupled to transmit the first transmission signal; and

a third port for transmitting the transmit feedback signal, wherein the third port is magnetically connected to the second port.

3. The transceiver of claim 1, further comprising an up converter circuit operable to receive the first transmission signal at baseband and up convert the first transmission signal into the first physical uplink channel.

4. The transceiver of claim 3, wherein the transmission amplification circuit is connected within the transmitter circuit so as to amplify the first transmission signal after being up converted into the first physical uplink channel by the up converter circuit.

5. The transceiver of claim 1, further comprising a multiplexer having:

a first port coupled to provide the first transmission signal within the first physical downlink channel to an antenna and to receive the first receive signal within the first physical downlink channel from the antenna;

a second port coupled to receive the first transmission signal within the first physical uplink channel from the transmitter circuit; and

a third port coupled to provide the first receive signal within the first physical downlink channel to the receiver circuit.

6. The transceiver of claim 1, wherein:

the first transmission signal comprises a first uplink data element, wherein the first uplink data element is associated with a first power adjustment time period for adjusting the current power level of the first transmission signal and is associated with the transmission power control information for adjusting the first transmission signal to the first desired power level;

the power control system being further adapted to;

repeatedly detect the difference between the current power level of the first transmission signal and the first desired power level during the first power adjustment time period; and

repeatedly adjust the first adjustable gain to reduce the difference between the current power level of the first transmission signal and the first desired power level during the first power adjustment time period so long as the difference indicates that the current power level and the first desired power level have not been substantially eliminated.

7. The transceiver of claim 6, wherein:

the transmission power control information includes power step information defining a magnitude of power change and direction information defining a direction of power change;

the power control system is further adapted to detect the difference between the current power level of the first transmission signal and the first desired power level during the first power adjustment time period by;

prior to adjusting the first adjustable gain, determining the current power level based on the signal level of the transmit feedback signal and determine the first desired power level based on the current power level, the power step information, and the direction information;

comparing the current power level and the first desired power level to provide a first gain adjustment for the first adjustable gain; and

after adjusting the first adjustable gain in accordance with the first gain adjustment, again determining the current power level based on the signal level of the transmit feedback signal so long as the difference indicates that the current power level and the first desired power level are not substantially equal; and

the power control system is further adapted to repeatedly adjust the first adjustable gain to reduce the difference between the current power level and the first desired power level during the first power adjustment time period so long as the difference indicates that the current power level and the first desired power level have not been substantially eliminated by;

adjusting the first adjustable gain in accordance with the first gain adjustment; and

after adjusting the first adjustable gain in accordance with the first gain adjustment, continually adjusting the first adjustable gain until the difference indicates that the current power level and the first desired power level have been substantially eliminated.

8. The transceiver of claim 6, wherein:

the first receive signal comprises a plurality of downlink data elements, each of the plurality of downlink data elements including the transmission power control information for adjusting the first transmission signal to a respective desired power level, wherein one of the plurality of downlink data elements includes the transmission power control information for adjusting the first transmission signal to the first desired power level;

the first transmission signal comprises one or more additional uplink data elements, each associated with a respective power adjustment time period for adjusting the current power level of the first transmission signal, wherein each of the one or more additional uplink data elements is associated with the transmit power control information of at least one of the plurality of downlink data elements; and

for each one of the one or more additional uplink data elements, the power control system is further adapted to adjust the first adjustable gain of the transmission amplification circuit, during a respective time period associated with the one of the one or more additional uplink data elements, based on the signal level of the transmit feedback signal and the transmission power control information associated with the one of the one or more additional uplink data elements so as to reduce a difference between the current power level of the first transmission signal and the respective desired power level.

9. The transceiver of claim 8, wherein each of the plurality of downlink data elements is selected from a group consisting of a downlink data frame defined by the first physical downlink channel, a downlink data sub-frame defined by the first physical downlink channel, and a downlink data slot defined by the first physical downlink channel.

10. The transceiver of claim 8, wherein each of the first uplink data element and the one or more additional uplink data elements is selected from a group consisting of an uplink data frame defined by the first physical uplink channel, an uplink data sub-frame defined by the first physical uplink channel, and an uplink data slot defined by the first physical uplink channel.

11. The transceiver of claim 10, wherein the respective power adjustment time period for each of the first uplink data element and the one or more additional uplink data elements is defined based on the each of the first uplink data element and the one or more additional uplink data elements.

12. The transceiver of claim 8, wherein:

each of the plurality of downlink data elements is selected from a group consisting of a downlink data frame defined by the first physical downlink channel, a downlink data sub-frame defined by the first physical downlink channel, and a downlink data slot defined by the first physical downlink channel; and

the respective power adjustment time period for each of the first uplink data element and the one or more additional uplink data elements is defined by the plurality of downlink data elements.

13. The transceiver of claim 1, wherein the first physical uplink channel is selected from a group consisting of an uplink dedicated physical control channel, an uplink enhanced dedicated physical control channel, an uplink common control channel, an uplink high speed dedicated physical control channel, and an uplink physical random access channel.

14. The transceiver of claim 1, wherein the first physical downlink channel is selected from a group consisting of a downlink dedicated physical channel, a downlink enhanced dedicated physical channel, a downlink fractional dedicated physical channel, a downlink enhanced dedicated relative grant channel, a downlink enhanced hybrid indicator channel, a downlink physical random access channel, a downlink primary common control physical channel, a downlink secondary common control physical channel, and a downlink high speed shared control physical channel.

15. The transceiver of claim 1, wherein the transmitter circuit is further operable to receive one or more additional transmission signals and to up convert each of the one or more additional transmission signals into one of one or more additional physical uplink channels, the transmitter circuit further comprising:

one or more additional transmission amplification circuits for each one of the one or more additional transmission signals, each of the one or more additional transmission amplification circuits having a respective adjustable gain and being operable to amplify the one of the one or more additional transmission signals in accordance with the respective adjustable gain; and

the power control system being operable to adjust the respective adjustable gain of each of the one or more additional transmission amplification circuits based on a relationship between the respective adjustable gain of the one or more additional transmission amplification circuits and the first adjustable gain of the transmission amplification circuit.

16. A method of controlling transmission power in a mobile user device communicating with a base station, comprising:

generating, at the mobile user device, a first transmission signal;

up converting, at the mobile user device, the first transmission signal into a first physical uplink channel utilizing a transmitter circuit;

amplifying the first transmission signal in accordance with a first adjustable gain by the transmitter circuit;

receiving, from the base station and at the mobile user device, transmission power control information for adjusting a current power level of the first transmission signal to a first desired power level;

transmitting, from the mobile user device and to the base station, the first transmission signal after the up converting of the first transmission signal into the first physical uplink channel;

detecting, at the mobile user device, a signal level of the first transmission signal within the transmitter circuit wherein the signal level is associated with the current power level of the first transmission signal;

adjusting the first adjustable gain to reduce a difference between the current power level and the first desired power level of the first transmission signal; and

adjusting an impedance response of an antenna tuner to reduce the difference between the current power level and the first desired power level of the first transmission signal when the maximum power level that is providable by the first adjustable gain is reached by a transmission amplification circuit and when the first desired power level is above the maximum power level of the transmission amplification circuit.

17. The method of claim 16,

wherein receiving, from the base station and at the mobile user device, the transmission power control information for adjusting the current power level of the first transmission signal to the first desired power level comprises receiving, at the mobile user device and from the base station, a first receive signal within a first physical downlink channel that includes the transmission power control information;

and

down converting the first receive signal out of the first physical downlink channel.

18. The method of claim 17, wherein:

the first receive signal comprises a plurality of downlink data elements, each of the plurality of downlink data elements including the transmission power control information for adjusting the first transmission signal to a respective desired power level, wherein one of the plurality of downlink data elements includes the transmission power control information for adjusting the first transmission signal to the first desired power level; and

the first transmission signal comprises a first uplink data element associated with a first power adjustment time period and with the transmission power control information for adjusting the first transmission signal to the first desired power level, and one or more additional uplink data elements each associated with a respective power adjustment time period and with the transmission power control information of one of the plurality of downlink data elements.

19. The method of claim 18, further comprising:

wherein adjusting the first adjustable gain to reduce the difference between the current power level and the first desired power level of the first transmission signal is performed during the first power adjustment time period so long as the current power level and the first desired power level are not substantially equal; and

for each one of the one or more additional uplink data elements, adjusting the first adjustable gain to reduce a difference between the current power level and the respective desired power level of the first transmission signal associated with the one of the one or more additional uplink data elements during the respective power adjustment time period so long as the current power level and the respective desired power level are not substantially equal.

20. A non-transitory computer readable medium that stores computer-executable instructions for implementing a method in a mobile user device, wherein the method comprises:

extracting transmission power control information from a first receive signal, wherein the transmission power control information is for adjusting a first transmission signal to a first desired power level;

receiving a transmit feedback signal from a transmitter circuit, wherein the transmitter circuit is operable to up convert a transmission signal into a first physical uplink channel, the transmit feedback signal having a signal level associated with a current power level of the first transmission signal;

determining a difference between the current power level of the first transmission signal and the first desired power level based on the signal level of the transmit feedback signal and the transmission power control information;

adjusting a first adjustable gain in a transmission amplification circuit within the transmitter circuit based on the difference between the current power level of the first transmission signal and the first desired power level; and

adjusting an impedance response of an antenna tuner to reduce the difference between the current power level of the first transmission signal and the first desired power level when a maximum power level that is providable by the first adjustable gain is reached by the transmission amplification circuit and when the first desired power level is above the maximum power level of the transmission amplification circuit.