Last years, Wavelet Packet Modulation (WPM) or Wavelet Packet Transform based Orthogonal Frequency Division Multiplexing (WPT-OFDM) have been introduced to wired and wireless communication fields as efficient Multicarrier Modulation (MCM) techniques. The wavelets have interesting features such as flexibility, compatibility and localization in both time and frequency domains with no need to use ...

orthogonal frequency division multiplexing (ofdm) has become a promising method for many wireless communication applications. however, one main drawback of ofdm systems is the high peak-to-average power ratio (papr). selected mapping (slm) is a well-known technique to decrease the problem of high papr in ofdm systems. in this method, transmitter is obliged to send some bits named side informati...

Orthogonal frequency division multiplexing (OFDM) has become a promising method for many wireless communication applications. However, one main drawback of OFDM systems is the high peak-to-average power ratio (PAPR). Selected mapping (SLM) is a well-known technique to decrease the problem of high PAPR in OFDM systems. In this method, transmitter is obliged to send some bits named side informati...

This paper presents an empirical mode decomposition (EMD) based adaptive filter (AF) for channel estimation in OFDM system.  In this method, length of channel impulse response (CIR) is first approximated using Akaike information criterion (AIC). Then, CIR is estimated using adaptive filter with EMD decomposed IMF of the received OFDM symbol. The correlation and kurtosis measures are used to sel...

in recent years, wavelet packet modulation ofdm (wpm-ofdm) signals have been introduced for radar applications. these signals have important properties such as inherent high range resolution and high resistance of radar system against jamming reception. this paper investigates the problem of designing these family of signals according to the following criteria: constrained maximization of the d...

This paper discusses an adaptive modulation technique combined with space-frequency block coded OFDM(SFBC OFDM) over frequency selective channels and evaluates the performance in terms of the outdated channel state information(CSI) in mobile environments. This paper employs the Alamouti’s diversity scheme in multiple input multiple output OFDM (MIMO OFDM) and an adaptive modulation with enhance...

For unmanned aerial vehicles (UAVs), high-precision measurement and high-speed communication are necessary to realize flight operational missions. In this paper, we propose an integrated system in a Doppler frequency offset environment. The combines orthogonal division multiplexing (OFDM) modulation with binary carrier (BOC) formulate OFDM+BOC composite signal through power control. High-precis...

Adaptive coded modulation is one of the key technologies used to enhance the capabilities of future communication network. Many adaptive modulation techniques have been investigated for the enhancement of transmission rate in combination with OFDM under AWGN channel .OFDM will provide much higher bandwidth efficiency. This is due to the fact that in OFDM the spectra of individual subcarriers ar...

in this paper the problem of minimizing the total transmitting power subject to a fixedtotal bit rate in ofdm systems is considered. upper bounds on transmitting power and bit rate ofeach subcarrier can also be taken into account. in practice, the number of bits of each subcarriershould be integer and nonnegative. in this paper an analytical optimal solution is derived for thecase of assuming t...