Orthogonal Frequency Division Multiple Access (OFDMA) has been selected as the multiple access technique to meet the growth of cellular subscribers and the need for faster and more reliable data services. The fundamental in OFDMA femtocell network is the interference management. When femtocell is deployed in the existing macrocell network, there will be a chance of interference between the femt...

We propose a hybrid multiple access (HMA) for uplink orthogonal frequency division multiple access (OFDMA) systems, which combines two resource sharing schemes: a scheduling-based resource allocation (SBRA) scheme and a contentionbased resource allocation (CBRA) scheme. The SBRA scheme is appropriate for non-real time high data rate traffic, and, CBRA is appropriate for near-real time low/mediu...

The Generalized Frequency Hopping (GFH) OFDMA system developed in this paper permeates FH bene ts to multicarrier CDMA transmissions through unknown frequencyselective multipath channels. No single user su ers from consistent fading e ects and multiuser interference is eliminated by design. Constellation-irrespective channel identi ability is guaranteed, and a host of blind channel estimation a...

We proposed a novel joint sub channel and resource allocation for the two-tier OFDMA network. The multi-cell OFDMA network not only has to control the interference to the users, but also has to coordinate the cross-tier interference. A resource allocation scheme for cross-channel Femto and Macro is proposed, aiming to maximize the capacity. We formulate this joint optimization for both uplink a...

This report is a tutorial on Orthogonal Frequency Division Multiplex (OFDM) and Orthogonal Frequency Division Multiple Access (OFDMA). OFDMA is the major transmission and access technology for future mobile broadband systems like Mobile WiMAX and 3GPP Long Term Evolution (LTE). One of the key features of OFDM and OFDMA is the ability to handle multipath propagation without complex receivers. Th...

To meet the requirements of high data rate, third generation partnership project (3GPP) has come across the development of long term evolution (LTE). High data rate can be achieved with the help of an advanced modulation method. Orthogonal Frequency Division Multiple Access (OFDMA) was considered as a modulation method especially in the downlink of the communication systems. It gives many advan...

Orthogonal Frequency Division Multiple Access (OFDMA) appears today as a strong candidate in on-going standardization. Despite its attractive features, it has several drawbacks when employed in the uplink: The high peak-to-average power ratio (PAPR) inherited from Orthogonal Frequency Division Multiplexing (OFDM) and the inherent frequency diversity loss. The loss of frequency diversity can be ...

Relay deployment in Orthogonal Frequency Division Multiple Access (OFDMA) based cellular networks helps in coverage extension and/or capacity improvement. To quantify capacity improvement, blocking probability of voice traffic is typically calculated using Erlang B formula. This calculation is based on the assumption that all users require same amount of resources to satisfy their rate requirem...

In this paper, we discuss CPM-OFDMA (Continuous Phase Modulation Orthogonal Frequency Division Multiple Access) a novel modulation that maps a discrete-time CPM into a spectrally efficient DFTspread OFDMA transmission. Three CPM-OFDMA schemes are developed based on discrete-time variants of PCM/FM, SOQPSK-TG and ARTM-CPM telemetry modulations. Simulations reveal that spectrally efficient CPM-OF...