Combined Digital-Analog Signal Processors, Waveforms with Time Constrained Signal (TCS) response and Long Response (LR) filtered Bit Rate Agile (BRA) Modulation-Demodulation (Modem) Format Selectable (MFS) and Code Selectable (CS) system implementations for Interoperable Multiple Standard Enhanced GSM, CSMA, TDMA, OFDM, and third-generation CDMA, W-CDMA and B-CDMA systems and associated methods Systems include Feher's Gaussian Minimum Shift Keying (GMSK or FGMSK) and Feher's Quadrature Phase Shift Keying (FQPSK) systems combined with Adaptive Antenna Arrays (AAA), Pseudo-Error (PE) based Non-Redundant Error Detection (NRED) controlled IF adaptive equalizers, smart antenna and smart diversity systems which have spectral/RF power efficiency and enhanced end-to-end performance

System and method for interoperable multiple-standard modulation and code selectable Feher's GMSK, enhanced GSM, CSMA, TDMA, OFDM, and third-generation CDMA, W-CDMA and B-CDMA

Spectral efficient transmitters-receivers (transceivers), modulation-demodulation (Modem) methods, architectures, structures and implementation technologies for enhanced performance and increased capacity CDMA, TDMA, GSM,OFDM, CMA, FDM and other wireless and wired communications, broadcasting and telemetry systems and integrated Modems/Transceivers suitable for operation over Non-Linearly Amplified (NLA) power efficient RF systems are described. Cross-correlated cascaded Time Constrained Signal (TCS) response processors and Long Response (LR) filtered Bit Rate Agile (BRA) in phase (I) and quadrature phase (Q) baseband signals are disclosed. These spectral efficient high performance processing, transmitting and receiving methods are designated as Feher's Quadrature Phase Shift Keying (FQPSK) Transceivers. Integrated Modem and transceiver technologies also disclosed herein and designated as Feher's Quadrature Amplitude Modulation (FQAM), Feher's Gaussian Minimum Shift Keying (FGMSK) and Feher's Minimum Shift Keying (FMSK) are subsets of 2nd generation FQPSK systems. Bit rate and RF agile embodiments are described. The 2nd generation of FQPSK systems with Adaptive Antenna Arrays (AAA) and adaptive Feher Equalizers (FE) and smart diversity systems has additional enhanced spectral/RF power efficiency and end-to-end performance advantages.

Spectrally efficient FQPSK, FGMSK, and FQAM for enhanced performance CDMA, TDMA, GSM, OFDN, and other systems

Receiver network for receiving a first filtered modulated transmitted signal in a first RF band and a second modulated transmitted signal in a second RF band and for providing received signals to one or more demodulators. A demodulator and baseband filter for demodulating and filtering the first filtered modulated received signal and for providing filtered demodulated baseband signal by a baseband filter mismatched to the filter of the first filtered modulated transmitted signal and demodulating the second modulated signal providing a demodulated baseband signal and a selector for selecting either the first or the second demodulated baseband signal. A receiver and demodulation system receiving a first TDMA modulated signal having a first bit rate and for receiving a second modulated signal having a second bit rate and for providing the received signals to a one or more demodulators and for providing cross-correlated demodulated in-phase and quadrature-phase baseband signals and demodulating the second bit rate modulated signal and providing a demodulated baseband signal.

Methods and systems for transmission of multiple modulated signals over wireless networks

Systems, apparatus, and methods for new generations of wireless systems, including multiple standard, interoperable Third-Generation (3G) and Second-Generation (2G), Spread Spectrum CDMA, WCDMA, GSM, Enhanced GSM systems and CSMA, TDMA and OFDM. Bit Rate Agile (BRA), Modulation and Code Selectable processing techniques of Gaussian Minimum Shiftl Keying (GMSK), Quadrature Phase Shift Keying (QPSK), Quadrature Amplitude Modulation (QAM), and of Mis-Matched demodulator filters in which the demodulator filter set is mis-matched to the filter set of the signal modulator.

Bit rate agile third-generation wireless CDMA, GSM, TDMA and OFDM system

A multipath propagation model for aeronautical telemetry over water at 8.0 GHz is presented. Data recorded during channel sounding experiments, conducted over the Pacific Ocean near Point Mugu, CA was used to model the multipath propagation. The modeling results show that a three-ray model consisting of line-of-sight propagation and two reflected propagation paths is a good fit for the measured channel frequency responses. One of the reflected propagation paths is a strong specular reflection determined by the geometry defined by the airborne transmitter, the ground-based receiver, and the sea surface. For the flight profiles used, the delay of this path is between 10 and 50 ns. The other propagation path is a more diffuse, random reflection whose amplitude is significantly smaller than the amplitude of the specular reflection and whose mean excess delay is 57 ns with an rms delay spread of 25 ns.

Multipath Channel Model for Over-Water Aeronautical Telemetry

A simple, low cost radio frequency (RF) power and spectrally efficient integrated transceiver/modem architecture employing Feher’s patented Quadrature Phase Shift Keying (FQPSK) is described. The FQPSK signals presented in this paper are obtained by using additional post low-pass filters in the FQPSK architecture. This implementation significantly improves the spectral efficiency of the worldwide commercially standardized Gaussian Minimum Shift Keying (GMSK) systems. The Bit Error Rate (BER) performance of FQPSK in additive white Gaussian noise (AWGN) channel has been investigated by means of computer simulation and hardware prototype measurements. The results of the hardware and software simulations are compared to GMSK and QPSK/OQPSK performance. These results show that the filtered FQPSK modulated signal passing through a non-linear amplifier (NLA) can achieve a spectral efficiency improvement of about 60% over NLA filtered OQPSK and an integrated spectral efficiency improvement of 50% over GMSK and a better BER performance. In particular, 100 kb/s to 34 Mb/s hardware experimental results over 2.4 GHz NLA (saturated) 1 Watt system confirmed that FQPSK hardware systems attain a BER=f(Eb/N0) performance within 1 dB to 2 dB of predicted theoretical results.

Fqpsk: a bandwidth and rf power efficient technology for telemetry applications

A carrier recovery circuit implementation with an all-digital reverse modulation approach for coherent detection in the GSM/GMSK system as well as the GMSK compatible improved efficiency cross-correlated FQPSK system is presented. The proposed carrier recovery implementation utilizes all-digital reverse modulation circuit in a feedback loop to remove the modulated signal from the received intermediate frequency (IF) signal and to estimate the phase error of this carrier signal using a phase-locked loop (PLL). The digital reverse modulation approach avoids the multipliers required in an analog reverse modulation design, so that it can be implemented in a single chip FPGA. Hardware implementation of the coherent detection demonstrates that cross-correlated FQPSK is completely compatible with GMSK in the system performance and the receiver structure for GSM. Experimental performance evaluations show that the proposed carrier recovery circuit provides a Bit Error Rate (BER) performance within 0.3 dB in a non-linearly amplified channel corrupted by additive white Gaussian noise (AWCN) as compared with the simulated performance of the GSM/GMSK system.

All-digital reverse modulation architecture based carrier recovery implementation for GMSK and compatible FQPSK

Blind adaptive equalization with application for Non-Linearly Amplified (NLA) quadrature amplitude modulation (QAM) systems in multipath selective fading channels is presented. With an offset sampling strategy in the receiver, the proposed blind equalization using Constant Modulus Algorithm (CMA) exhibits a fast convergent speed for a family of quadrature modulated systems in NLA and multipath fading channels. Feher’s patented Quadrature Phase Shift Keying (FQPSK) and Feher’s Quadrature Amplitude Modulation (FQAM) which correspond respectively to 4-state and 16-state QAM are used due to their higher Radio Frequency (RF) power and spectral efficiency in NLA channel. It has been shown that blind adaptive equalization can significantly open the eye signals in multipath frequency selective fading channels.

Blind equalization for fqpsk and fqam systems in multipath frequency selective fading channels

Ultra-broadband thermal radiator for daytime passive radiative cooling based on single dielectric SiO2 on metal Ag

Design and performance evaluation of a low-complexity equalizer for recently standardized spectral efficient Feher patented quadrature phase shift keying (FQPSK) system [1] over multipath fading channel is presented. The implementation based on a Feher patented equalizer (FE) [1] is of a structure with three branches, which are individually used to compensate for a moving fade notch with different locations. These branches are switched by the control signal that is generated based on pseudo-error on-line detection technique. It is demonstrated that for typical aeronautical telemetry RF frequency selective fading channels, having delay spreads in 20 – 200 ns range, the adaptive FE reduces the number of statistical outages by more than 60% without the need for training bits and without increasing the receiver synchronization time.

Wei Gao

Papers

Fqpsk: a bandwidth and rf power efficient technology for telemetry applications

All-digital reverse modulation architecture based carrier recovery implementation for GMSK and compatible FQPSK

Blind equalization for fqpsk and fqam systems in multipath frequency selective fading channels

Ultra-broadband thermal radiator for daytime passive radiative cooling based on single dielectric SiO2 on metal Ag

Tests and evaluations of adaptive feher equalizers for a large class of systems, including fqpsk