Edge transceiver architecture and related methods

• US 7,720,176 B2
• Filed: 08/25/2006
• Issued: 05/18/2010
• Est. Priority Date: 09/26/2005
• Status: Expired due to Fees

• Current Assignee: ST-Ericcson SA (Telefonaktiebolaget LM Ericsson)
• Original Assignee: ST-Ericcson SA (Telefonaktiebolaget LM Ericsson)
• Inventors: Welland, David
• Primary Examiner(s): VO, DON NGUYEN
• Application Number:
  US11/510,339
• Publication Number:
  US 20070071129A1
• Time in Patent Office: 1,362 Days
• Field of Search: 375/302, 375/305, 375/308, 332/100, 332/119, 332/145, 332/151, 455/61, 455102-104
• US Class Current: 375/302
• CPC Class Codes: H04B 1/04 Circuits
• CPC Class Codes: H04L 27/0008 arrangements for allowing a transmitter or receiver to use more than one type of modulation negotiating modulation type for two-way transmission paths H04L5/1453

Abstract

In one embodiment, the present invention includes an apparatus having multiple transmission paths, including a first transmission path configured to receive and process baseband data in a first mode of operation to generate a radio frequency (RF) signal for output via a common output path, and a second transmission path configured to receive and process the baseband data in a second mode of operation to generate the RF signal for output via the common output path.

Claims

1. An apparatus comprising:

a first transmission path to receive and process baseband data in a first mode of operation to generate a radio frequency (RF) signal for output via a common output path wherein generation of the RF signal includes, at a mixer, coupling baseband data to one or more mixer slices thereby providing a digital variable gain amplifier;

a second transmission path to receive and process the baseband data in a second mode of operation to generate the RF signal for output via the common output path wherein generation of the RF signal is characterized by coupling, at a mixer, additional mixer slices at a fixed current density; and

a multiplexer arranged to provide the incoming baseband signals to a selected one of the first and second transmission paths in the first and second modes of operation respectively.

2. The apparatus of claim 1, wherein the apparatus is to reuse at least a portion of the first transmission path in the second mode of operation, wherein the first transmission path is to provide an unmodulated carrier signal to the second transmission path in the second mode of operation.

3. The apparatus of claim 1, further comprising a multiplexer to receive the baseband data and to provide the baseband data to the first transmission path in the first mode of operation, and to provide a predetermined value to the second transmission path in the first mode of operation.

4. The apparatus of claim 1, wherein the first transmission path comprises an offset phase lock loop (OPLL) including:

a phase detector coupled to an output of a first mixer, the phase detector further coupled to receive a feedback signal from a second mixer;

a filter coupled to receive and filter an output of the phase detector;

a local oscillator coupled to an output of the filter to output a modulated signal in the first mode of operation, wherein the local oscillator is to output an unmodulated signal in the second mode of operation; and

the second mixer coupled to receive an output of the local oscillator.

5. The apparatus of claim 4, wherein the local oscillator is coupled to provide the modulated signal to a mixer of the second transmission path in the first mode of operation.

6. The apparatus of claim 5, wherein the mixer of the second transmission path is to buffer and provide the modulated signal to the common output path.

7. The apparatus of claim 5, wherein the OPLL is to provide the unmodulated signal to the mixer of the second transmission path in the second mode of operation.

8. The apparatus of claim 7, wherein the mixer of the second transmission path is to mix the baseband data with the unmodulated signal in the second mode of operation.

9. The apparatus of claim 5, wherein the mixer of the second transmission path comprises a commutating mixer having a plurality of circuitry slices individually controllable to control a gain of the RF signal.

10. The apparatus of claim 5, wherein the second transmission path comprises:

an analog amplifier coupled to receive the baseband data; and

a filter coupled between an output of the analog amplifier and the mixer of the second transmission path.

11. The apparatus of claim 10, wherein a gain of the analog amplifier is to be continuously controlled.

12. The apparatus of claim 1, wherein the RF signal includes amplitude and phase information in the second mode of operation.

13. The apparatus of claim 12, wherein the first mode of operation includes a GMSK modulation scheme and the second mode of operation includes an 8-PSK modulation scheme.

14. A system comprising:

a first transmitter path to receive first baseband data and generate a gaussian minimum shift keying (GMSK) radio frequency (RF) signal in a GMSK mode of operation wherein generating of the GMSK RF signal includes controlling current density of the first baseband data and coupling the first baseband data to at least one of a plurality of mixer slices at a mixer for mixing with a local oscillator signal;

a second transmitter path to receive second baseband data and generate an 8 phase shift keying (8-PSK) RF signal in an 8-PSK mode of operation wherein the received second baseband data is coupled to additional mixer slices at a fixed current density, and wherein the second transmitter path is to buffer the GMSK RF signal in the GMSK mode of operation; and

a power amplifier coupled to the second transmitter path.

15. The system of claim 14, wherein the second transmitter path comprises a direct upconversion transmitter.

16. The system of claim 15, further comprising a transceiver including the first transmitter path and the second transmitter path, wherein the transceiver is controllable in an open loop configuration or in a closed loop configuration.

17. The system of claim 16, further comprising a feedback path coupled to receive an output of the power amplifier, the feedback path further comprising a second amplifier to amplify a difference between a value representative of the power amplifier output and a reference signal received from a baseband processor coupled to the transceiver.

18. The system of claim 14, wherein the first transmitter path comprises:

a phase detector coupled to an output of a first mixer, the phase detector further coupled to receive a feedback signal from a second mixer;

a filter coupled to receive and filter an output of the phase detector;

a local oscillator coupled to an output of the filter to output a modulated signal in the GMSK mode of operation, wherein the local oscillator is to output the unmodulated carrier signal in the 8-PSK mode of operation; and

the second mixer coupled to the receive an output of the local oscillator.

19. The system of claim 18, wherein the second transmitter path comprises:

an analog amplifier coupled to receive the second baseband data;

a filter coupled to an output of the analog amplifier; and

a mixer coupled to an output of the filter to mix the second baseband data with the unmodulated carrier signal from the first transmitter path in the 8-PSK mode of operation.

20. The system of claim 19, wherein a gain of the analog amplifier is to be continuously controlled.

21. The system of claim 20, further comprising a transceiver including the first transmitter path and the second transmitter path, wherein the transceiver is controllable in an open loop configuration or in a closed loop configuration.

22. The system of claim 21, further comprising a feedback path coupled to receive an output of the power amplifier, the feedback path further comprising a second amplifier to amplify a difference between a value representative of the power amplifier output and a reference signal received from a baseband process or coupled to the transceiver, wherein an output of the second amplifier is to control the analog amplifier.

23. A method comprising:

providing first incoming baseband signals to a first transmission path of a transceiver, wherein the first incoming baseband signals are for a first wireless communication protocol, and processing the first incoming baseband signals in an offset phase lock loop (OPLL) of the first transmission path including controlling current density of the first incoming baseband signal by coupling the first incoming baseband signal to at least one of a plurality of mixer slices so as to obtain first radio frequency (RF) signals; and

providing second incoming baseband signals to a second transmission path of the transceiver, wherein the second incoming baseband signals are for a second wireless communication protocol, and modulating an unmodulated output signal of the OPLL with the second incoming baseband signals and additional mixer slices at a fixed current density to obtain second RF signals in the second transmission path.

24. The method of claim 23, further comprising buffering the first RF signals in the second transmission path.

25. The method of claim 23, further comprising providing a fixed input to the second transmission path while providing the first incoming baseband signals to the first transmission path.

26. The method of claim 23, further comprising controlling the first transmission path according to an open loop model or a closed loop model based on a system in which the transceiver is located.