Wireless Communication Receivers Research Articles

8.1 nJ/b 2.4 GHz Short-Range Communication Receiver in 65 nm CMOS

An 8.1 nJ/bit 2.4 GHz receiver with integrated digital baseband supporting O-QPSK DSSS modulation compliant with the IEEE 802.15.4 standard is presented that targets short-range, Internet of Things applications (IoTs). The sensitivity of a wireless communication receiver in general trades with power consumption. This receiver exploits this tradeoff to achieve a total power consumption of 2.02 mW including ADCs and digital baseband processing, at a sensitivity of $-$ 52.5 dBm at 250 Kbps. The energy-efficiency of the radio frequency (RF) front-end alone is nearly 2x better than the prior art. The receiver was fabricated in 65 nm CMOS with an area of 0.86 ${\rm mm}^{2}$ .

Compact UWB Micro Strip Band Pass Filter with Open Circuited Stubs

A filter is a key and critical component for all types of wireless communication receivers, which are used to reject the noises (unwanted frequencies) in accordance with the applications. Band pass filters enable operation of any given module in a particular frequency range. In this paper, a compact microstrip band pass filter is proposed with operating range from 2.7 to 10.7 GHz for Ultra-Wide band (3.1 to 10.6 GHz) applications. The Chebychev elliptic function filtering method is employed. Two open circuited stubs are used to achieve the upper transmission loss and coupled micro strip structure is used to reduce transmission loss. The designed filter has insertion loss greater than -1 dB and return loss lower than -10 dB in pass band. The filter is designed with dimensions of 10mm x 9mm x 1.6mm on FR4 (er = 4.3) substrate. The sharp cut-off at lower and upper stop bands has been achieved by proper tuning of the widths and lengths of the open circuited stubs. Bandwidth of about 8 GHz and a flat group delay in the pass band have been achieved. In view of its compactness, this filter can be easily integrated with all communication devices. The designed band pass filter has potential and promising application in UWB (Wi-Fi, Wi-Max, WLAN and ITU) applications.

A Wide Bandwidth Analog Baseband Circuit for 60-GHz Proximity Wireless Communication Receiver in 65-nm CMOS

A Wide Bandwidth Analog Baseband Circuit for 60-GHz Proximity Wireless Communication Receiver in 65-nm CMOS

Wireless Condition Monitoring of Train Traction Systems Using Magnetoelectric Passive Current Sensors

Novel power-supply-free, surface-mount-type magnetoelectric passive current sensors were developed and integrated with a four-channel, 2.4-GHz wireless communication (transmitter and receiver) unit to form a new generation of wireless condition monitor for train traction systems. The wireless condition monitor was deployed in a field study on the East Rail Line in Hong Kong. Four pairs of magnetoelectric passive current sensors and single-channel wireless transmitters were installed, respectively, on and near the electric cables of four electric motor drives located underneath the 2 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">nd</sup> , 5 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sup> , 8 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sup> , and 11 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sup> cars of a 12-car mainline train. The four-channel wireless receiver was housed in the driver's cab of the train to provide real-time wireless monitoring of the current signatures of the four electric motor drives due to the operation of the train traction system in steady-state and acceleration conditions. The monitored current signatures were post-processed to obtain the distributions of the ratio of harmonic-to-fundamental current, their total harmonic distortions and power factors as well as the frequency spectra. A practical implication and correlation of the post-processed data with the operating conditions of the train traction system was established for application of the proposed wireless condition monitor as train traction system monitor.

Integrated D-band transmitter and receiver for wireless data communication in 65 nm CMOS

A 140 GHz transmitter (Tx) and receiver (Rx) chip set has been developed in 65 nm CMOS by using on---off keying non-coherent modulation to support high speed proximity data communication. To the author's best knowledge, it enables the first integrated multi-Gbps data link in D-band by saving power hungry frequency synthesizer, high speed data convertors and complicated digital signal processor. The Tx and Rx occupy 0.03 and 0.12 mm2 chip areas, respectively. To validate the communication at 140 GHz carrier frequency, a data link has been built to demonstrate up to 2.5 Gbps data rate with power consumption of 115/120 mW for Tx/Rx respectively.

PIN Photodiode Optoelectronic Integrated Receiver Used for 3-Gb/s Free-Space Optical Communication

In this paper, an optoelectronic integrated receiver chip including five PIN photodiodes will be presented. A large 200-μm diameter photodiode connected to a high-speed transimpedance amplifier works as a 3-Gb/s receiver for optical wireless communication. Four surrounding photodiodes allow for the adjustment of the incoming laser ray. The complete chip was realized in a silicon 0.35-μm BiCMOS technology to benefit from the available intrinsic zone in this technology. Due to this intrinsic zone and an antireflection coating, the responsivity reaches a value of more than 0.5 A/W for wavelengths from 630 to 760 nm. Furthermore, the capacitance of the center photodiode is less than 0.6 pF for reverse bias voltages larger than 3 V. For proof of concept, a steerable and adjustable light source was built based on a micro-electro-mechanical system mirror, on a focusing unit, and on a direct modulated vertical cavity surface emitting laser with a wavelength of 680 nm. The complete system is capable of establishing a 3-Gb/s data transfer over a distance of 19 m at a BER of <;10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-9</sup> , and over a distance of 18 m at a BER of <;10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-12</sup> .

Advanced continuous phase modulation for high mobility communications

This paper focuses on the design of continuous phase-modulated systems and simplified receiver for high-mobility wireless communications. A class of spectrally efficient coded modulation systems is proposed and analyzed in terms of Euclidean distance and spectral efficiency. Moreover, the simplified detector based on mismatched receiver is designed to reduce the detection complexity exponentially for partial response systems. To deal with the fast time-varying channels without channel state information, a class of noncoherent detection algorithms for continuous phase modulation systems is developed to offer near-coherent performance. The proposed system is assessed over both the additive white Gaussian noise and fast-fading channels. Numerical and simulated results show that the proposed system offers not only high spectral efficiency but also near-optimum performance over fast time-varying scenarios.

Gigahertz Flexible Graphene Transistors for Microwave Integrated Circuits

Flexible integrated circuits with complex functionalities are the missing link for the active development of wearable electronic devices. Here, we report a scalable approach to fabricate self-aligned graphene microwave transistors for the implementation of flexible low-noise amplifiers and frequency mixers, two fundamental building blocks of a wireless communication receiver. A devised AlOx T-gate structure is used to achieve an appreciable increase of device transconductance and a commensurate reduction of the associated parasitic resistance, thus yielding a remarkable extrinsic cutoff frequency of 32 GHz and a maximum oscillation frequency of 20 GHz; in both cases the operation frequency is an order of magnitude higher than previously reported. The two frequencies work at 22 and 13 GHz even when subjected to a strain of 2.5%. The gigahertz microwave integrated circuits demonstrated here pave the way for applications which require high flexibility and radio frequency operations.

Performance optimization of iterative receiver for wireless communications based on realistic channel conditions

Adopting orthogonal frequency division multiplexing (OFDM) to low-density parity check (LDPC) coded multiple-input multiple-output (MIMO) is attractive scheme for wireless communication systems. An iterative receiver design for LDPC coded MIMO-OFDM system is proposed as the foundation for enhancing the wireless link performance can deliver the coverage, speed, throughput and reliability. However, in previous works, evaluations are basically assumed for a certain channel scenario and it is inefficient in incorporating different channel scenarios. The aim of this paper is to improve the system range for equivalent error rate, while not significantly increasing system complexity compared to conventional iterative receiver solution under realistic channel environment. We show that our proposed iteration adaptation at receiver can considerably adopt the system to realistic change environment, and reach very high reliability. Simulations of our optimization reveal superior error rate performance and lower computational cost vs. conventional LDPC coded MIMO OFDM system. Our simulation results also capture the effects of realistic vs. typical channel fading types (i.e., Rician vs. Rayleigh, respectively) and fading parameter models (average vs. random azimuth spread and K factor) on system performance and complexity.

Filling the Spectral Holes: Novel\/Future Wireless Communications and Radar Receiver Architectures

The requirement of wireless access by novel telecommunications and remote-sensing applications, such as Internet-in-mobile services and ultrawideband (UWB) radar systems, is continuously growing in western society but also in countries with big and emerging economies such as China, Brazil, India, and even some African nations. As a consequence, the radiofrequency (RF) spectrum is becoming a very valuable but scarce natural resource. In relation to this, it is well known that some portions of the RF spectrum, such as those assigned to military and emergency services, remain underutilized. These spectral holes, usually referred as white spaces, then become excellent opportunities for new wireless communications and radar systems to operate. Nevertheless, the necessary dynamic access to properly exploit these free spectral holes can only be performed through very sophisticated and reliable receiver architectures. They must be capable of sensing very broad spectrum ranges while assuring a minimum quality for the received signals. This article addresses modern RF receiver schemes for sensing widebands in communications and radar scenarios.

Design considerations of conventional angle diversity receivers for indoor optical wireless communications

Abstract A conventional angle diversity receiver uses multiple receiving elements that are oriented in different directions, where each element employs its own filter and nonimaging concentrator, such as a compound parabolic concentrator (CPC) or hemispheric lens. In this paper, a study of the design of a conventional receiver structure using angle diversity that offers improved performance with respect to the infrared channel characteristics is presented. To this end, a recently proposed model for the effective signal collection area of a conventional angle diversity receiver that more closely approximates real behaviour than the ideal model is used. The inclusion of this model in a Monte Carlo ray-tracing algorithm allows us to investigate the effects of conventional receiver parameters on the main infrared channel parameters, such as path loss and rms delay spread. Furthermore, in order to determine the number of receiver elements, the outage probability and the average error probability are also considered. Based on the results, a conventional angle diversity receiver composed of seven elements is proposed, with one of them oriented towards the ceiling, and six angled at a 56° elevation with a 60° separation in azimuth. For each element, a CPC with a 50° field of view must be used.

A Low-Complexity Uniform and Non-uniform Digital Filter Bank Based on an Improved Coefficient Decimation Method for Multi-standard Communication Channelizers

It has been shown in literature that the coefficient decimation (CD) techniques can be efficiently used to realize low-complexity finite impulse response (FIR) filters with flexible frequency responses. In this paper, we propose a novel filter bank (FB) design technique based on the combination of the conventional coefficient decimation method (CDM) and the modified coefficient decimation method recently proposed by us. In the proposed FB, subbands of desired bandwidths are obtained by the spectral subtraction of the lowpass and highpass frequency responses obtained after performing CD operations on the prototype filter, using appropriate decimation factors. The proposed FB that provides uniform as well as non-uniform subbands can be used for multi-standard channelization in wireless communication receivers. We show that the proposed FB has a significantly lower complexity along with superior stopband and transition band characteristics when compared with the conventional CDM-based progressive decimation filter bank (PDFB). The design example shows that the proposed FB offers 74 % reduction in multiplication complexity over the PDFB, when used for non-uniform multi-standard channelization with a fixed frequency channel distribution. If the same FB is used for multi-standard channelization with variable locations of the frequency channels, a substantial 95.67 % reduction in multiplication complexity is achieved over the PDFB.

Design of Bandwidth Adjustment Receiver for Optical Wireless Communication

Infrared wireless communication possesses two main attractive advantages over its radio frequency counterpart, namely the abundance of unregulated spectrum in 700nm - 1500nm region and the ease with which the IR radiation can be confined. Integrating microwave electronics and optics, it is possible to provide wideband communication services but it is well known that the signal level in an optical wireless receiver is weakest at the front end. This paper presents the concerned with a systematic approach to the design of receiver for indoor optical wireless communication. In particular, it is concerned with how one properly chooses the front-end preamplifier and biasing circuitry for the photodetector; and comparison of technique using bandwidth adjustment for better service quality with a bootstrapped transimpedance amplifier is presented. A controllable capacitance is introduced at the output of the second stage of the amplifier. This technique permits a bandwidth adjustment from 52Hz to 233MHz for a capacitance range of 10uF to 1pF.

A 1-V 1.2-mW CMOS medradio receiver for biomedical applications

An ultra-low-power low-voltage 401–406 MHz Medical Device Radiocommunications Service (MedRadio) receiver for continuous wireless communication in biomedical applications is demonstrated using 0.18-μm CMOS technology. Although using a low-IF architecture, careful consideration is done for individual block-level circuit design to minimize the overall power consumption. The receiver chain consists of a complementary current-reuse LNA, an in-phase/quadrature folded mixer, an eighth-order complex bandpass filter, a limiting amplifier chain with RSSI, and a frequency synthesizer with a quadrature VCO. The proposed receiver achieves a gain of over 80 dB, noise figure of 14 dB, image rejection of 32 dB, and phase noise of −106 dBc/Hz at 100 kHz offset while consuming less than 1.2 mW from a 1-V supply voltage with 1.8 mm2 of core die area. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2821–2825, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27205

Low Noise Amplifier for 2.45 GHz Frequency Band at 0.18 μm CMOS Technology for IEEE Standard 802.11 b/g WLAN

This paper presents the design of low noise amplifier (LNA) at 2.45 GHz and integrated at 0.18 µm RF CMOS process technology. This type of LNA at 2.45 GHz is use in the Bluetooth receiver. The proposed method is useful to optimize noise performance and power gain while maintaining good input and output matching. The amplifier is designed to be used as first stage of a receiver for wireless communication. The main aim of designer is to achieve low noise figure with improved gain with the help of CMOS technology by using single stage n-MOS amplifier. The simulation results show a forward gain of 14.0 dB, a noise-figure of 0.5 dB and stability factor is approximate unity, in which the circuit operates at 14.2 mA drain current with supply voltage of 3.5 V and biasing voltage of 1.5 V.

Design and implementation of a low-power OFDM receiver for wireless communications

Orthogonal Frequency-Division Multiplexing (OFDM) systems can efficiently combat the issue of frequency-selective fading channels. Therefore, OFDM has become one of the most popular baseband modulation techniques for wireless communications. This paper presents the design and implementation of a low-power OFDM baseband receiver for wireless local area networks (WLAN). The proposed architecture employs low-power register files and resource-sharing techniques, thus consuming less power than many existing works. The proposed design adopts a number of area-efficient hardware structures to further reduce the hardware cost. Finally, because it is designed using 0.18 μm CMOS technology, the core of the proposed chip has approximately 239K gates, and its power consumption is approximately 36 mW at 20 MHz.

The Design for Multi-Point Wireless Temperature and Humidity Acquisition USB-Based

Wireless temperature and humidity acquisition system is designed in this paper using PT100 thermal resistances and HS1101 sensors. The system is composed of thermal resistances using C8051f330 microcontroller with two-wire resistance measurement circuits, HS1101 frequency output circuits, 2.4 GHz ISM band RF transceiver chips nRF24L01 with multi-point sending and receiving, combination of wireless communication receiver modules CY7C68013. System uses the USB2.0 send temperature and humidity data to the PC, and display the curves of LabWindows / CVI real-time temperature and humidity.

Wavelet—Artificial Neural Network Receiver for Indoor Optical Wireless Communications

The multipath-induced intersymbol interference (ISI) and fluorescent light interference (FLI) are the two most important system impairments that affect the performance of indoor optical wireless communication systems. The presence of either incurs a high optical power penalty and hence the interferences should be mitigated with suitable techniques to ensure optimum system performance. The discrete wavelet transform (DWT) and the artificial neural network (ANN)-based receiver to mitigate the effect of FLI and ISI has been proposed in the previous study for the ON-OFF keying (OOK) modulation scheme. It offers performance improvement compared to the traditional methods of employing a high-pass filter and a finite impulse response equalizer. In this paper, the investigation of the DWT-ANN-based receiver for baseband modulation techniques including OOK, pulse position modulation, and digital pulse interval modulation is reported. The proposed system is implemented using digital signal processing board and results are verified by comparison with simulation data.

A Frequency Synthesizer With Optimally Coupled QVCO and Harmonic-Rejection SSBmixer for Multi-Standard Wireless Receiver

This paper presents a wide-band fractional-N frequency synthesizer for multi-standard cellular and short-range wireless communication receivers. The synthesizer covers the frequency band from 1.8 to 6 GHz and supports the standards of DCS1800, WCDMA, TD-SCDMA, WLAN802.11 a/b/g and Bluetooth. Architecture design and frequency planning are carefully performed to tradeoff wide frequency range and power efficiency. A quadrature voltage-controlled oscillator (QVCO) with a new phase shifter scheme is developed which shows better phase noise performance and more stable oscillation. Combining harmonic rejection and single sideband mixing, a harmonic-rejection SSBmixer (HR-SSBmixer) is developed to suppress unwanted sidebands and spurious signals. It serves as a power-saving solution to generate the LO signal for the 802.11a mode by avoiding power-hungry poly-phase filters or high-frequency LO buffers and dividers. The synthesizer is designed in a 0.13-μm CMOS technology. It occupies an active area of 1.86 mm2 and consumes 35.6 to 52.62 mW of power. Measurement results show that the synthesizer is able to provide in-phase and quadrature-phase (I/Q) signals supporting the standards mentioned above.

A novel, low‐complexity, high‐speed envelope detector and its applications

SUMMARYA compact and effective transmission envelope detector (TED), which can detect whether the absolute amplitude of an input differential signal is larger than a threshold or not, is proposed. The TED has been demonstrated to be applicable for received signal strength indicator circuit in wireless communication receivers or power management systems, and mode‐control circuit in bidirectional optical transceivers. Implemented in a 0.18 µm CMOS technology, the TED has a response time of 210 ps at 5 Gbps, occupies an active area of 0.05 mm2, and consumes 1 mA from 1.8 V supply. Copyright © 2011 John Wiley &amp; Sons, Ltd.