A Digitally Intensive Transmitter/PA Using RF-PWM With Carrier Switching in 130 nm CMOS

Cho, Kunhee; Gharpurey, Ranjit

doi:10.1109/jssc.2015.2512932

Cited by 30 publications

(17 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The infinite number of terms in the summation of Equation 13 shows that S k (jΩ) has theoretically an unlimited bandwidth; however, the frequency content of S k (jΩ) is reduced to a negligible level with increasing |Ω|. The infinite number of terms in the summation of Equation 13 shows that S k (jΩ) has theoretically an unlimited bandwidth; however, the frequency content of S k (jΩ) is reduced to a negligible level with increasing |Ω|.…”

Section: Analysis Of Analog Pwm With Delayed Referencementioning

confidence: 99%

“…[7][8][9][10][11][12][13][14][15][16] In a conventional PWM-based transmitter, the magnitude of RF signal is converted into a two-level square wave with variable pulse-width. [7][8][9][10][11][12][13][14][15][16] In a conventional PWM-based transmitter, the magnitude of RF signal is converted into a two-level square wave with variable pulse-width.…”

Section: Introductionmentioning

confidence: 99%

“…In recent years, the concept of PWM-based RF power amplification has been frequently addressed as a promising approach toward highly efficient RF transmitters. [7][8][9][10][11][12][13][14][15][16] In a conventional PWM-based transmitter, the magnitude of RF signal is converted into a two-level square wave with variable pulse-width. This conversion is performed through modulating the envelope of the RF input into the duty cycles of a periodic pulse train.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

High dynamic range pseudo–two‐level digital pulse‐width modulation for power‐efficient RF transmitters

Arian

Jannesari

2018

Circuit Theory & Apps

View full text Add to dashboard Cite

Radio frequency (RF) power amplification based on pulse-width modulation (PWM) has been widely discussed as a potential solution to achieve higher efficiency in RF transmitters. A digitally implemented PWM introduces a large amount of in-band distortion due to spectral aliasing. In this paper, a novel memoryless PWM modulator with a built-in anti-aliasing filter is proposed that effectively reduces the in-band distortion in digital implementation. The spectral characteristics of the proposed PWM modulator as well as the statistical properties of its output PWM signal are analytically studied. The pseudotwo-level output of the proposed modulator provides the capability to compromise between the efficiency, linearity, and complexity of transmitter, based on the given design targets. The proposed PWM method benefits from a simple circuit implementation in both digital and RF sections of the transmitter.Moreover, it preserves the low distortion property at low oversampling ratios of digital baseband. Simulations, as well as measurements, verify the performance of the proposed method. low level of RF input signal, PA consumes no power, while at the high level, PA can be designed to work in saturated output power where it presents the best efficiency performance.Although PA in a PWM-based transmitter operates in its most power-efficient regions, converting RF magnitude into the pulse train generates a significant amount of unwanted frequency components in the output spectrum of PA. 17 As depicted in Figure 2, these spurs are located at integer multiples of PWM frequency ( f PWM ) around the RF carrier frequency ( f c ). The bandpass filter (BPF) in Figure 1 is located at the output of PA to remove these undesired spurs and obtain the amplified version of the RF input. The quality of the signal recovered by BPF highly depends on the amount of distortion around the band of interest in the spectrum of RF PWM signal. The dynamic range (DR) gives a criterion to measure this type of distortion. It is defined as the ratio between the average power of the desired in-band signal and the power of the surrounding distortion, which is given in dB (or dBc). A sufficiently high DR is essential at the output spectrum of PA to satisfy the in-band signal quality and tight spectral requirements imposed by modern wireless standards. This is not feasible unless the RF PWM signal driving the PA itself benefits from excellent spectral characteristics.The spectral characteristics of the analog PWM (APWM) signal have been frequently studied in previous works. [17][18][19][20][21][22] An APWM signal occupies a wide bandwidth with a spectral content that tends to roughly roll-off as ∝ 1= f f PWM with increasing the frequency. By choosing a large enough PWM frequency, f PWM , of the APWM modulator, an arbitrary high DR could be theoretically achieved 19,21 at the cost of a wider output spectral bandwidth. Nevertheless, the practical achievable DR of the modulator is significantly restricted by the accuracy and bandwidth limitation of its analog ...

show abstract

Section: Analysis Of Analog Pwm With Delayed Referencementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

High dynamic range pseudo–two‐level digital pulse‐width modulation for power‐efficient RF transmitters

Arian

Jannesari

2018

Circuit Theory & Apps

View full text Add to dashboard Cite

show abstract

“…Different fully digital modulation and amplification schemes using PWM have been proposed, such as “baseband PWM” and “RF PWM.” In baseband PWM, PWM is performed on the amplitude baseband signal, and the RF signal is obtained by multiplying it with a PM square wave carrier . In the case of RF PWM, the predistorted baseband amplitude and the phase are pulse‐width modulated using a PWM frequency equal to the carrier frequency . It was shown that differential RF PWM is equivalent to an outphasing modulator where a square wave rather than a sinusoidal wave is used for the carrier signal …”

Section: Introductionmentioning

confidence: 99%

“…[12][13][14][15] In the case of RF PWM, the predistorted baseband amplitude and the phase are pulse-width modulated using a PWM frequency equal to the carrier frequency. [16][17][18][19][20] It was shown that differential RF PWM is equivalent to an outphasing modulator where a square wave rather than a sinusoidal wave is used for the carrier signal. 21 The problem of using conventional digital PWMs directly on the RF signal is that a very-high-PWM frequency is required, which results in very narrow pulses that are difficult to generate and amplify correctly by the switched amplifier.…”

Section: Introductionmentioning

confidence: 99%

Table‐based PWM for all‐digital RF transmitters

Morales

Chierchie

Mandolesi

et al. 2018

Circuit Theory & Apps

View full text Add to dashboard Cite

Summary In this paper, a novel pulse‐width modulator (PWM) for an all‐digital PWM transmitter based on switching amplification is presented. In this approach, each symbol is represented by a sequence of pre‐computed PWM pulse widths stored in a table that results in reduced error vector magnitude (EVM). A high‐resolution pulse former is then used to build the bipolar radio frequency (RF) signal. Simulations and comparisons to other approaches reported in the literature under different oversampling ratios and finite time resolutions are presented. The impact of nonlinearities in the variable duty‐cycle generator is also analyzed to demonstrate the robustness of the proposed technique.

show abstract

Design of low power RF CMOS power amplifier structure with an optimal linear gain controller for future wireless communication

ArjunaraoVatti

Kumar

Haripriya

et al. 2021

J Ambient Intell Human Comput

View full text Add to dashboard Cite

A Digitally Intensive Transmitter/PA Using RF-PWM With Carrier Switching in 130 nm CMOS

Cited by 30 publications

References 17 publications

High dynamic range pseudo–two‐level digital pulse‐width modulation for power‐efficient RF transmitters

High dynamic range pseudo–two‐level digital pulse‐width modulation for power‐efficient RF transmitters

Table‐based PWM for all‐digital RF transmitters

Design of low power RF CMOS power amplifier structure with an optimal linear gain controller for future wireless communication

Contact Info

Product

Resources

About