Recently, we proposed to combine time sharing with hierarchical modulation to increase the transmission rate of broadcast systems. Our proposal involves to group the receivers in pairs in order to transmit with hierarchical modulation. We introduced several grouping strategies but the optimal matching remained an open question. In this letter, we show that the optimal grouping is the solution o...

| Coded modulation schemes for hierarchical broadcasting employing multilevel coding (MLC) are considered for both, AWGN and at Rayleigh fading channels. Design rules for signal constellations and codes are discussed. The superiority of hierarchical schemes based on MLC over time-sharing is shown.

In this study, we use hierarchical modulation technology to estimate the carrier frequency offset (CFO) caused by the Doppler effect; and hierarchical modulation has been implemented in the orthogonal frequency-division multiplexing (OFDM) system. Different threshold levels have been used to demodulate various bits of the hierarchical modulated symbols and it has the characteristic that the bit...

Hierarchical modulation (HM) is able to provide different levels of protection for data streams and achieve a rate region that cannot be realized by traditional orthogonal schemes, such as time division (TD). Nevertheless, criterions and algorithms for general HM design are not available in existing literatures. In this paper, we jointly optimize the constellation positions and binary labels fo...

In this paper, we analyze the conventional closed-loop power-control system. We explain that the system behaves essentially as a companded delta modulator and then derive an expression for the power-control error in terms of the channel fading, which suggests methods for reducing the error variance. This is achieved by using a prediction technique for estimating the channel-power fading profile...