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A six-port Ka-band front-end architecture based on direct conversion for a software-defined radio application is proposed in this paper. The direct conversion is accomplished using six-port technology. In order to demodulate various phase-shift-keying/quadrature-amplitude-modulation (PSK/QAM) modulated signals at a high bit rate, a new analog baseb...
Context in source publication
Context 1
... -band prototype front-end was fabricated using a mono- lithic hybrid microwave integrated circuit (MHMIC) six-port [11]. The baseband circuit was realized with conventional op- erational amplifiers according to Fig. 3. The diagram of the baseband circuit, realized using current feedback operational amplifiers type OPA 2658 is shown in Fig. 4. This operational amplifier has a cut-off frequency of 800 MHz. In the first stage, the six-port dc output voltages are amplified by around 20 dB. Then, two differential amplifiers are used to obtain signals according to (15) and (16). Finally, these signals are once again ...
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Citations
... Table III provides a detailed performance summary of the presented integrated SiPh SDR and contrasts it with other state-of-the-art designs. These include the time-approximation filter [18], the N -path filters from RFIC 2021 [19] and RFIC 2020 [20], as well as the six-port discriminator microwave IC presented in [21]. In our approach, we harness the potential of the PIC to facilitate blocker rejection using a fourth-order BPF and notch filters. ...
... Our design operates in the 30-45-GHz mmwave band, surpassing the frequency range of all referenced works. In addition, it supports a versatile bandwidth range of 3-5 GHz, which is broader than the best-reported bandwidth of 4 GHz from [21]. For narrowband interferers, the blocker rejection value reaches up to 80 and 60 dB for quad interferers. ...
... Moreover, this work introduces a comprehensive PIC filter structure that efficiently addresses the challenges often associated with implementing higher order analog IIR filters on CMOS chips. The design uniquely supports automatic calibration of center frequency, bandwidth, and off-band rejection, surpassing capabilities in prior works [18], [19], [20], [21]. In addition, RF downconversion is demonstrated, with the balanced PD current being amplified and detected. ...
This article presents a re-configurable hybrid millimeter-wave (mm-wave) software-defined radio (SDR) receiver that integrates silicon photonics (SiPhs) and complementary metal–oxide–semiconductor (CMOS) chips. The SDR system leverages a programmable photonic integrated circuit (PIC) with high-
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$>$
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$>$
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$-$
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$-$
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... Since 1972, the six-port reflectometer [1][2] has been considered as a simpler and less expensive solution to replace the bulky and costly measurement equipment, which is the conventional network analyzer using the heterodyne principle. The six-port technique has experienced significant progress especially in the field of measurement [1][2][3][4][5][6][7][8][9] or telecommunications [10][11][12][13][14][15][16][17][18] as well as for other applications such as radar systems [19][20][21]. The most frequent use of this device is for measuring both the amplitude and the phase of the reflection coefficient of a device under test (DUT). ...
In this paper, a wideband reflectometer based on six-port technology is presented. The designed six-port junction is built by using a modified ring power divider and three identical 90-degree hybrid couplers. The main difference from its initial application as a conventional six-port reflectometer is the addition of a fourth qi point. Here, the four power detectors are used to find the reflection coefficient (4 qi points) and a fifth detector is added as a reference. To simplify the fabrication process and minimize the cost, the six-port circuit is designed on a single-layer PCB. The measured results of the six-port junction reveal high performance over a large frequency band from 2.2 to 3.55 GHz. In order to evaluate its performance for real-time measurements, the proposed six-port reflectometer is then tested by measuring the reflection coefficient of different devices under test (DUTs). The measured results are then corrected by a simplified calibration method to have optimal results. Compared to conventional six-port calibration methods, the proposed calibration process is simple and allows accurate reflection coefficient measurements. After calibration, there is a great improvement in the corrected results of the reflection coefficient compared to the measured results which proves that the calibration process works perfectly from 2.6 to 3.8 GHz.
... This six-port technology, which was developed for direct-conversion radio receivers, has been studied for many applications [10], [11]. It can improve the performance of a receiver, especially in terms of bit error rate (BER) [12]. For this work, the proposed methodology can be summarized as follows: ...
... The attenuator is adjusted to have a power of 25 dBm at reference port 5. The six-port circuit has three hybrid couplers with a 90 degree phase shift and a Wilkinson power divider [12], [22]. The six-port technology is used in the receiver part for various reasons: it provides a straightforward direct demodulation of quadrature demodulation schemes (M-QAM, PSK), a low-cost demodulator containing only passive circuits and four diodes, and good dynamic range. ...
Noise reduction is one of the most important process used for signal processing in communication systems. The signal-to-noise ratio (SNR) is a key parameter to consider for minimizing the bit error rate (BER). The inherent noise found in millimeter-wave systems is mainly a combination of white noise and phase noise. Increasing the SNR in wireless data transfer systems can lead to reliability and performance improvements. To address this issue, we propose to use a recurrent neural network (RNN) with a long short-term memory (LSTM) autoencoder architecture to achieve signal noise reduction. This design is based on a composite LSTM autoencoder with a single encoder layer and two decoder layers. A V-band receiver test bench is designed and fabricated to provide a high-speed wireless communication system. Constellation diagrams display the output signals measured for various random sequences of PSK and QAM modulated signals. The LSTM autoencoder is trained in real time using various noisy signals. The trained system is then used to reduce noise levels in the tested signals. The SNR of the designed receiver is of the order of 11.8dB, and it increases to 13.66dB using the three-level LSTM autoencoder. Consequently, the proposed algorithm reduces the bit error rate from 10
<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−8</sup>
to 10
<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−11</sup>
. The performance of the proposed algorithm is comparable to other noise reduction strategies. Augmented denoised signals are fed into a ResNet-152 deep convolutional network to perform the final classification. The demodulation types are classified with an accuracy of 99.93%. This is confirmed by experimental measurements.
... The frequency response of the reflection coefficient of two types of transitions are shown in Fig. 7. It is clear that both transitions have properly satisfied the impedance matching requirements (S11 ≤ -20 dB) over the bandwidth of interest (27)(28)(29)(30)(31)(32)(33). To realize the BSAN, all components including hybrid coupler, transitions, feeding network, and antenna elements are ready to be assembled in the entire design. ...
... The experimental and numerical results of the scattering parameters related to the proposed BSAN are presented in Fig. 11. It is notable that the results are obtained when one of the input ports is excited, namely port 1. Apparently, both the matching and isolation levels are at a strong level (≤ -15 dB) over the bandwidth of interest (27)(28)(29)(30)(31)(32)(33). In addition, the gain curve of the proposed BSAN is shown in Fig. 11, as well. ...
... It means that ω = ω0, corresponding to ∆ꞷ(t)=0. Assuming that four similar detectors are utilized, the dc output voltages are obtained, as [32] ...
The manuscript presents the design and characterization of a wideband front-end receiver, based on hollow waveguide technology, for the wireless access point (WAP) applications. The Ka-band receiver is comprised of a low-loss beam-switching antenna network (BSAN) with two-dimensional (2D) scanning property. For demodulation, the receiver uses an efficient six-port network (SPN) that is composed of four 90: hybrid couplers and a 90: phase shifter. To suppress the phase imbalance on the entire band of interest, 27 GHz to 33 GHz, a frequency-independent phase shifter with a minimum phase error is suggested. The SPN receiver is integrated with antenna-in-package in waveguide technology to decrease the insertion losses and noise levels at the first stages. To determine the SPN phase errors, a theoretical and experimental analysis of real-time wireless data transmission utilizing phase-shift keying (PSK) and quadrature amplitude modulated (QAM) signal is conducted. Besides, channel capacity along with beamformer influence on channel performance improvement are determined.
... Complicated calibration procedures are therefore avoided due to a careful circuit design and fabrication procedure, for each frequency band and specific targeted application. Figure 1 shows a typical implementation of a quadrature down-converter in a front-end block diagram [38]. The received signal from the antenna (or antenna array in mm-wave communication receivers or radars), amplified (if needed) by a low-noise amplifier (LNA), a 6 , is compared with the reference signal generated by the LO, namely a 5 . ...
... It was previously demonstrated [38] that: vIF I (t)= AIF[v3(t) − v1(t)] = αKa 2 AIF cos[∆ (t) + φ(t)], ...
... It was previously demonstrated [38] that: ...
Recent advances in millimeter wave technologies, both in component and system design, in line with important size and cost reductions, have opened up new applications in ultra-high-speed wireless communications, radar and imaging sensors. The paper presents the evolution of millimeter wave circuit and modules fabrication and characterization technologies in the past decades. Novel planar low-cost fabrication technologies have been successfully developed in this period. In combination with the standard rectangular wave-guide technology, these offer great opportunities for prototyping and testing of future millimeter wave transceivers or front-ends, which integrate antenna arrays, down-converters, modulators, amplifiers, etc., in a compact fixture. The paper uses, as a suggestive example, the evolution of the multi-port interferometric front-ends implementation from millimeter wave bulky components and systems to miniaturized and high-efficient ones. Circuit and system designs are carefully done to avoid (as much as possible) complicated calibration methods or difficult post-processing of baseband data. This requires an increased effort in design and fabrication, but it allows miniaturization, low-power consumption, while keeping very good overall performances. Useful and straightforward laboratory characterization techniques of circuits and systems are described in detail.
... It is common to use diodes, to perform nonlinear mixing, and a low pass filter to extract the desired baseband parts in outputs of the six-port correlator, as depicted in Figure 1. All formulas which are published for analysing the six-port receiver's performance have modelled diode behaviour as an squared law model (Ghannouchi and Mohammadi, 2009;Askari and Kamarei, 2017;Djoumessi et al., 2009;Bao et al., 2012;Djoumessi and Wu, 2010;Huyart and Khy, 2012;Koelpin et al., 2011;Osth et al., 2010;Tatu et al., 2005;Winter et al., 2007;Zhang et al., 2017;Chagtmi et al., 2017;Song et al., 2018;Neveux et al., 2004;Moscoso-Martir et al., 2011;Mohajer et al., 2007). In this paper, an analytical approach for diode power detector is presented and its influence on six-port receiver performance is studied. ...
Purpose
The purpose of this paper is to study the effect of diode power detector modelling on six-port communication receiver performance.
Design/methodology/approach
Based on proposed and conventional squared diode model, six-port receiver’s demodulation and its error vector magnitude (EVM) performance due to hardware impairments are studied. Through considering both the models, the accuracy of proposed power detector model is compared to the squared model, and then both results are validated with envelope simulation (ENV) in advanced design system (ADS).
Findings
Comparing the numerical results with envelope simulation results proved that the proposed model is much more accurate than the conventional squared model for a wide range of input power levels.
Originality/value
Studying the receiver’s performance numerically, by considering the new proposed analytical approach for diode power detectors which is more accurate than the conventional squared model.
... Nowadays millimeter wave components are requested more and more for very promising applications, such as multi-Gb/s wireless links, radar and imaging sensors. Six-ports have been used for decades in microwave bands and due to their well-known quadrature down-conversion and direct modulation applications; they also play an important role in millimeter wave transceiver implementation [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. There is an increase in the use of microstrip antenna because of its lightweight, low fabrication costs, the capability of supporting multiple frequency bands, and integration with multiple input multiple output (MIMO) [6]. ...
... There is an increase in the use of microstrip antenna because of its lightweight, low fabrication costs, the capability of supporting multiple frequency bands, and integration with multiple input multiple output (MIMO) [6]. The disadvantages associated with this approach include; dielectric losses, surface wave losses, decreased gain, narrow bandwidth due to conductor losses, and large PCB structure [7]. ...
... A harmonic balance analysis is performed as an initial design validation of the interferometric capabilities of the six-port circuit [7]. The block diagram of harmonic balance simulation is presented in igure 23. ...
The study has presented an extensive analysis of an integrated millimeter wave six-port interferometer, operating over a 10 GHz band, from 80 to 90 GHz. It has covered both semi-unlicensed point-to-point links (81-86 GHz), and imaging sensor system frequencies (above 85 GHz). An in-house process is used to fabricate miniaturized hybrid millimeter wave integrated circuits on a very thin ceramic substrate. Two-port S-parameter measurements are performed on a minimum number of circuits integrated on the same die, exploiting the circuit’s physical symmetry and chosen to collect enough data for full-port characterization. Based on these measurements on an integrated prototype, a six-port circuit computer model implemented and advanced system simulations performed for circuit analysis. Interferometer performances evaluated using several methods: analysis of harmonic balance, qi points’, homodyne quadrature demodulation, and error vector modulation (EVM). The analysis showed that this circuit can directly perform, without any calibration, the demodulation of various PSK and QAM signals over the 10 GHz band, with very good results.
... Four diode-based power detectors are connected to the output ports of the circuit, and two differential amplifiers can be used in order to obtain the in-phase output and the quadrature signals (I and Q). These I and Q signals, and the related complex demodulated Γ, are expressed as: [31]: ...
This paper outlines the design and implementation of a continuous-wave linear-frequency-modulated sensor for short-range radar applications. Low-cost technologies have been selected to implement the sensor. It was integrated on a 0.127-mm-thin ceramic substrate using the miniature hybrid microwave integrated circuit technology. Two 16-dBi gain
$8\times 2$
patch antenna arrays are implemented in the transmitter and receiver modules. The receiver is a six-port homodyne quadrature down-converter. The integrated power detectors are fabricated using HSCH-9161 Schottky diodes. The complete sensor, in the metallic fixture, measures
$35\times 45$
mm. The performance of the sensor to detect a target range and velocity is validated using system simulations and measurement systems on a test bench. System simulations use computer models based on S-parameter measurement results. Measurements show that an accuracy of
$\pmb {\pm } 16.23~ {\mu }\text{m}$
can be achieved with the sensor over a range of 15cm. To precisely measure the six-port radar accuracy, due to our RF laboratory capabilities, this result is obtained by changing the electrical length, instead of varying the physical distance.
... It must be noted that the obtained analytical expression of the complex vector (t) is the same used in the classical six-port receiver theory [19]. ...
... This paper presents the application of six-port interferometry in accurate CFO measurements. Without any calibration, thanks to its specific architecture, the six-port interferometer determines the vector relationship between the two-input millimeter-wave signals: the received one and its own LO, the reference signal [8]. This system operates with reduced LO power which is a striking advantage, especially in millimeter-wave designs, where high power levels are more challenging and costly to generate. ...
... The front-end section is composed of a receiver antenna, a six-port interferometer, and the related power detectors. The power detectors deliver quadrature differential signals measuring the frequency, phase and amplitude differences between the RF input unknown signal (a6) and the reference signal (a5) given by the LO, as proposed from the early period of six-port interferometry in transceivers, at lower operating frequencies [8]. ...
A V-band front-end based on a six-port interferometer is proposed for the accurate measurement of Carrier Frequency Offset (CFO) and carrier recovery in a wireless system. The interferometer uses power readings for amplitude, phase or frequency comparison between its two RF inputs. If the circuit is carefully designed, this low-cost technique allows precise phase and frequency measurements without the need of any calibration. Furthermore, the ability to work with a reduced local oscillator (LO) power is a significant advantage of interferometry versus conventional mixing techniques. Measurements performed at 64 GHz show a resolution of a few Hz, as low as permitted by today's DC-coupled measurement equipment. A CFO of 3 Hz, equivalent with a Doppler shift corresponding to a velocity of 7 mm/s, has been successfully measured.
