Method and system for polar modulation with discontinuous phase
Aspects of a method and system for polar modulation with discontinuous phase are provided. In this regard, in-phase and quadrature-phase components may be generated from a modulated baseband signal, and the signal components may be utilized to generate a signal representative of the amplitude of the baseband signal. Furthermore, the signal components may be pulse shaped and the pulse-shaped components may be divided by the signal representative of the amplitude of the baseband signal. The resulting signals may be up-converted to RF, summed, and amplified, where the amplification may be controlled via a quantized representation of the signal representative of the amplitude of the baseband signal. In this regard, one or more bias points, and/or one or more binary weighted current sources coupled to one or more power amplifiers may be controlled. The pulse-shaping may comprise passing the signal components through a raised cosine filter.
1. A method comprising:
generating, from in-phase and quadrature-phase components of a modulated baseband signal, a first signal representative of an amplitude of said baseband signal and one or more second signals representative of a phase of said baseband signal;
phase modulating an RF carrier signal utilizing said one or more second signals;
inputting said phase modulated RF signal to a cascaded plurality of amplifiers; and
configuring said cascaded plurality of amplifiers to amplitude modulate said phase modulated signal, wherein;
said configuring is based on a quantized representation of said first signal;
each of said plurality of amplifiers is configurable into only two configurations, a first of said two configurations comprising an amplifying configuration, and a second of said two configurations comprising a buffering configuration or a pass-through configuration;
wherein the number of said cascaded plurality of amplifiers is determined based on said quantized representation of said first signal.
2. The method according to claim 1 , wherein each possible value of said quantized representation of said first signal corresponds to a particular number of said amplifiers being configured into said amplifying configuration.
3. The method according to claim 1 , further comprising pulse-shaping said in-phase and quadrature phase components, wherein said pulse-shaping comprises a raised cosine function.
4. The method according to claim 1 , comprising controlling a bias point of said one or more power amplifiers utilizing said quantized representation of said signal representative of an amplitude of said baseband signal.
5. The method according to claim 4 , comprising controlling said bias point via a binary weighted current source.
6. The method according to claim 1 , wherein there is a one-to-one correspondence between amplifiers in said plurality of amplifiers and quantization levels utilized for said quantized representation of said first signal.
7. The method according to claim 1 , wherein the number of quantization levels utilized for said quantized representation of said first signal is determined based on the modulation present in said baseband signal.
8. The method according to claim 7 , wherein said baseband signal is a quadrature amplitude modulated (QAM) signal.
9. A non-transitory machine-readable storage having stored thereon, a computer program having at least one code section for signal processing, the at least one code section being executable by a machine for causing the machine to perform steps comprising:
generating, from in-phase and quadrature-phase components of a modulated baseband signal, a first signal representative of an amplitude of said baseband signal and one or more second signals representative of a phase of said baseband signal;
phase modulating an RF carrier signal utilizing said one or more second signals;
inputting said phase modulated RF signal to a cascaded plurality of amplifiers; and
configuring said cascaded plurality of amplifiers to amplitude modulate said phase modulated signal, wherein;
said configuring is based on a quantized representation of said first signal;
each of said plurality of amplifiers is configurable into only two configurations, a first of said two configurations comprising an amplifying configuration, and a second of said two configurations comprising a buffering configuration or a pass-through configuration;
wherein the number of said cascaded plurality of amplifiers is determined based on said quantized representation of said first signal.
10. The non-transitory machine-readable storage according to claim 9 , wherein said at least one code section comprises code for wherein each possible value of said quantized representation of said first signal corresponds to a particular number of said amplifiers being configured into said amplifying configuration.
11. The non-transitory machine-readable storage according to claim 9 , wherein said at least one code section comprises code for pulse-shaping said in-phase and quadrature phase components, wherein said pulse-shaping comprises a raised cosine function.
12. The non-transitory machine-readable storage according to claim 9 , wherein said at least one code section comprises code for controlling a bias point of said one or more power amplifiers utilizing said quantized representation of said signal representative of an amplitude of said baseband signal.
13. The non-transitory machine-readable storage according to claim 12 , wherein said at least one code section comprises code for controlling said bias point via a binary weighted current source.
14. The non-transitory machine-readable storage according to claim 9 , wherein there is a one-to-one correspondence between amplifiers in said plurality of amplifiers and quantization levels utilized for said quantized representation of said first signal.
15. The non-transitory machine-readable storage according to claim 9 , wherein the number of quantization levels utilized for said quantized representation of said first signal is determined based on the modulation present in said baseband signal.
16. The non-transitory machine-readable storage according to claim 15 , wherein said baseband signal is a quadrature amplitude modulated (QAM) signal.
17. A system comprising:
one or more circuits operable to:
generate, from in-phase and quadrature-phase components of a modulated baseband signal, a first signal representative of an amplitude of said baseband signal and one or more second signals representative of a phase of said baseband signal;
phase modulate an RF carrier signal utilizing said one or more second signals;
input said phase modulated RF signal to a cascaded plurality of amplifiers; and
configure said cascaded plurality of amplifiers to amplitude modulate said phase modulated signal, wherein;
said configuration is based on a quantized representation of said first signal;
each of said plurality of amplifiers is configurable into only two configurations, a first of said two configurations comprising an amplifying configuration, and a second of said two configurations comprising a buffering configuration or a pass-through configuration;
wherein the number of said cascaded plurality of amplifiers is determined based on said quantized representation of said first signal.
18. The system according to claim 17 , wherein each possible value of said quantized representation of said first signal corresponds to a particular number of said amplifiers being configured into said amplifying configuration.
19. The system according to claim 17 , wherein said one or more circuits perform pulse-shaping of said in-phase and quadrature phase components, wherein said pulse-shaping comprises a raised cosine function.
20. The system according to claim 17 , wherein said one or more circuits control a bias point of said one or more power amplifiers utilizing said quantized representation of said signal representative of an amplitude of said baseband signal.
21. The system according to claim 20 , wherein said one or more circuits control said bias point via a binary weighted current source.
22. The system according to claim 17 , wherein there is a one-to-one correspondence between amplifiers in said plurality of amplifiers and quantization levels utilized for said quantized representation of said first signal.
23. The system according to claim 17 , wherein the number of quantization levels utilized for said quantized representation of said first signal is determined based on the modulation present in said baseband signal.
24. The system according to claim 23 , wherein said baseband signal is a quadrature amplitude modulated (QAM) signal.