Digitally controlled edge interpolator (DCEI) for digital to time converters (DTC)

• US 9,137,084 B2
• Filed: 08/02/2013
• Issued: 09/15/2015
• Est. Priority Date: 08/02/2013
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Degani, Ofir, Banin, Rotem, Ravi, Ashoke
• Primary Examiner(s): Timory, Kabir A
• Application Number:
  US13/958,295
• Publication Number:
  US 20150036767A1
• Time in Patent Office: 774 Days
• Field of Search: 375/298, 375/300, 375/308
• US Class Current: 1/1
• CPC Class Codes: H03F 1/0216 Continuous control
• CPC Class Codes: H03F 3/2175 using analogue-digital or digital-analogue conversion H03F3/2173 takes precedence
• CPC Class Codes: H03F 3/245 with semiconductor devices only
• CPC Class Codes: H04L 27/36 Modulator circuits; Transmitter circuits

Abstract

A Digital-to-Time (DTC) for a Digital Polar Transmitter (DPT) comprises a coarse delay/phase segment and a fine delay/phase segment. The coarse delay/phase segment generates an even delay/phase signal and an odd delay/phase signal. The fine/phase delay segment receives the even coarse phase signal and the odd coarse phase signal, and is responsive to a fine delay/phase control signal to generate a fine delay/phase output signal that is an interpolation of the even delay/phase signal and the odd delay/phase signal. In one exemplary embodiment, the fine delay/phase control signal comprises a binary signal having 2^N values, and the fine delay/phase segment comprises 2^N interpolators. Each interpolator is coupled to the even and odd coarse phase signals and is controlled by the fine delay/phase control signal to be responsive to the even coarse phase signal or the odd coarse phase signal based on a value of the fine delay/phase control signal.

Claims

1. A digital-to-time converter (DTC), comprising:

a coarse phase segment generating a coarse phase signal, the coarse phase signal comprising an even phase signal and an odd phase signal; and

a digitally controlled edge interpolator comprising a fine phase segment comprising an even coarse phase input and an odd coarse phase input, the even coarse phase input receiving the even coarse phase signal, the odd coarse phase input receiving the odd coarse phase signal, the fine phase segment responsive to a fine phase control signal to generate a fine phase output signal that is an interpolation of the even phase signal and the odd phase signal;

wherein the digitally controlled edge interpolator comprises an array of inverters having inputs fed by at least two or more adjacent coarse delay signals from the coarse phase segment to provide the fine phase output signal that is an interpolation of the even phase signal and the odd phase signal.

2. The DTC according to claim 1, wherein the fine phase control signal comprises a binary signal having 2^N values in which N comprises an integer equal to or greater than 2, and

wherein the fine phase segment further comprises 2^N interpolators, each interpolator being coupled to the even coarse phase signal and the odd coarse phase signal and being controlled by the fine phase control signal to be responsive to the even coarse phase signal or the odd coarse phase signal based on a value of the fine phase control signal, an output of each interpolator being coupled together to form the fine phase output signal.

3. The DTC according to claim 2, wherein if a value M of the fine phase control signal equals 0 (M=0), then all interpolators are responsive to the even coarse phase signal,

wherein if 0<

M<

2^N, then M interpolators are responsive to the even coarse phase signal and 2^N−

M interpolators are responsive to the odd coarse phase signal; and

wherein if M=2^N, then all 2^N interpolators are responsive to the odd coarse phase signal.

4. The DTC according to claim 2, wherein if a value M of the fine phase control signal equals 0, then all interpolators are responsive to the odd coarse phase signal,

wherein if 0<

M<

2^N, then M interpolators are responsive to the odd coarse phase signal and 2^N−

M interpolators are responsive to the even coarse phase signal; and

wherein if M=2^N, then all 2^N interpolators are responsive to the even coarse phase signal.

5. The DTC according to claim 1, wherein the fine phase output signal is a phase modulation signal for a digital polar transmitter signal.

6. The DTC according to claim 1, wherein the DTC comprises part of a digital polar transmitter (DPT).

7. The DTC according to claim 6, wherein the digital polar transmitter comprises part of a cellular telephone, smartphone, smart-type device, or tablet-type device.

8. The DTC according to claim 7, wherein the cellular telephone, smartphone, smart-type device, or tablet-type device further comprises a touchscreen display capable of receiving input information from a touch of a user or a stylus.

9. A digital polar transmitter, comprising:

a digital-to-time converter (DTC), comprising a coarse phase segment and a digitally controlled edge interpolator comprising a fine phase segment, the coarse phase segment generating an even phase signal and an odd phase signal from a local oscillator signal, the fine phase segment receiving the even coarse phase signal and the odd coarse phase signal, and the fine phase segment responsive to a fine phase control signal to generate a fine phase signal output signal that is an interpolation of the even phase signal and the odd phase signal;

wherein the digitally controlled edge interpolator comprises an array of inverters having inputs fed by at least two or more adjacent coarse delay signals from the coarse phase segment to provide the fine phase output signal that is an interpolation of the even phase signal and the odd phase signal; and

a digital power amplifier coupled to the fine phase output signal and receiving an amplitude modulation signal, the digital power amplifier being responsive to the fine phase signal and the amplitude modulation signal to output an amplitude- and phase-modulated signal to be transmitted, the fine phase output signal comprising a phase modulation signal for the digital polar transmitter.

10. The digital polar transmitter according to claim 9, wherein the fine phase control signal comprises a binary signal having 2^N values in which N comprises an integer equal to or greater than 2, and

wherein the fine phase segment further comprises 2^N interpolators, each interpolator being coupled to the even coarse phase signal and the odd coarse phase signal and being controlled by the fine phase control signal to be responsive to the even coarse phase signal or the odd coarse phase signal based on a value of the fine phase control signal, an output of each interpolator being coupled together to form the fine phase output signal.

11. The digital polar transmitter according to claim 10, wherein if a value M of the fine phase control signal equals 0 (M=0), then all interpolators are responsive to the even coarse phase signal,

wherein if 0<

M<

2^N, then M interpolators are responsive to the even coarse phase signal and 2^N−

M interpolators are responsive to the odd coarse phase signal; and

wherein if M=2^N, then all 2^N interpolators are responsive to the odd coarse phase signal.

12. The digital polar transmitter according to claim 10, wherein if a value M of the fine phase control signal equals 0, then all interpolators are responsive to the odd coarse phase signal,

wherein if 0<

M<

2^N, then M interpolators are responsive to the odd coarse phase signal and 2^N−

M interpolators are responsive to the even coarse phase signal; and

wherein if M=2^N, then all 2^N interpolators are responsive to the even coarse phase signal.

13. The digital polar transmitter according to claim 12, wherein the digital polar transmitter comprises part of a digital polar transmitter (DPT).

14. The digital polar transmitter according to claim 13, wherein the digital polar transmitter comprises part of a cellular telephone, smartphone, smart-type device, or tablet-type device.

15. The digital polar transmitter according to claim 14, wherein the cellular telephone, smartphone, smart-type device, or tablet-type device further comprises a touchscreen display capable of receiving input information from a touch of a user or a stylus.

16. A method to generate a fine phase signal for a digital-to-time (DTC) converter of a digital polar transmitter, the method comprising:

generating a coarse phase signal comprising an even phase signal and an odd phase signal; and

generating, with a digitally controlled edge interpolator, a fine phase output signal that is an interpolation of the even phase signal and the odd phase signal based on a fine phase control signal, the fine phase control signal comprising a binary signal having 2^N values in which N comprises an integer equal to or greater than 2, the fine phase output signal comprising a phase modulation signal for a digital polar transmitter signal,

wherein said generating the fine phase output signal comprises feeding at least two or more adjacent coarse delay signals to the digitally controlled edge interpolator to provide the fine phase output signal that is an interpolation of the even phase signal and the odd phase signal.

17. The method according to claim 16, wherein generating the fine phase output signal comprises controlling 2^N interpolators with the fine phase control signal, each interpolator being coupled to the even coarse phase signal and the odd coarse phase signal and being controlled by the fine phase control signal to be responsive to the even coarse phase signal or the odd coarse phase signal based on a value of the fine phase control signal, an output of each interpolator being coupled together to form the fine output signal.

18. The method according to claim 17, wherein if a value M of the fine phase control signal equals 0 (M=0), then all interpolators are responsive to the even coarse phase signal,

wherein if 0<

M<

2^N, then M interpolators are responsive to the even coarse phase signal and 2^N−

M interpolators are responsive to the odd coarse phase signal; and

wherein if M=2^N, then all 2^N interpolators are responsive to the odd coarse phase signal.

19. The method according to claim 17, wherein if a value M of the fine phase control signal equals 0, then all interpolators are responsive to the odd coarse phase signal,

wherein if 0<

M<

2^N, then M interpolators are responsive to the odd coarse phase signal and 2^N−

M interpolators are responsive to the even coarse phase signal; and

wherein if M=2^N, then all 2^N interpolators are responsive to the even coarse phase signal.

20. An information-handling system, comprising:

a processor and a memory coupled to the processor; and

a radio-frequency transceiver coupled to the processor, the radio-frequency transceiver comprising a digital polar transmitter comprising a digital power amplifier and a digital-to-time converter (DTC), the DTC comprising;

a coarse phase segment generating a coarse delay/phase signal, the coarse phase signal comprising an even delay/phase signal and an odd phase signal; and

a digitally controlled edge interpolator comprising a fine phase segment comprising an even coarse phase input and an odd coarse phase input, the even coarse phase input receiving the even coarse phase signal, the odd coarse phase input receiving the odd coarse phase signal, the fine phase segment responsive to a fine phase control signal to generate a fine phase output signal that is an interpolation of the even phase signal and the odd phase signal, and the fine phase output signal comprising a phase modulation signal for a digital polar transmitter signal;

wherein the digitally controlled edge interpolator comprises an array of inverters having inputs fed by at least two or more adjacent coarse delay signals from the coarse phase segment to provide the fine phase output signal that is an interpolation of the even phase signal and the odd phase signal.

21. The information-handling system according to claim 20, wherein the fine phase control signal comprises a binary signal having 2^N values in which N comprises an integer equal to or greater than 2, and

wherein the fine phase segment further comprises 2^N interpolators, each interpolator being coupled to the even coarse phase signal and the odd coarse phase signal and being controlled by the fine phase control signal to be responsive to the even coarse phase signal or the odd coarse phase signal based on a value of the fine phase control signal, an output of each interpolator being coupled together to form the fine phase output signal.

22. The information-handling system according to claim 21, wherein if a value M of the fine phase control signal equals 0 (M=0), then all interpolators are responsive to the even coarse phase signal,

wherein if 0<

M<

2^N, then M interpolators are responsive to the even coarse phase signal and 2^N−

M interpolators are responsive to the odd coarse phase signal; and

wherein if M=2^N, then all 2^N interpolators are responsive to the odd coarse phase signal.

23. The information-handling system according to claim 21, wherein if a value M of the fine phase control signal equals 0, then all interpolators are responsive to the odd coarse phase signal,

wherein if 0<

M<

2^N, then M interpolators are responsive to the odd coarse phase signal and 2^N−

M interpolators are responsive to the even coarse phase signal; and

wherein if M=2^N, then all 2^N interpolators are responsive to the even coarse phase signal.

24. The information-handling system according to claim 20, wherein the information-handling system comprises a cellular telephone, smartphone, smart-type device, or tablet-type device.

25. The information-handling system according to claim 24, wherein the cellular telephone, smartphone, smart-type device, or tablet-type device further comprises a touchscreen display capable of receiving input information from a touch of a user or a stylus.