R. Steele’s research while affiliated with University of Southampton and other places

... Here, PCSI at the legitimate receiver was assumed to benefit these conventional schemes. We also considered the classic differential star-QAM (SQAM) [72] and the conventional nonsquare DUC (N-DUC) [33], both of which worked efficiently without CSI. As a reference, the massive MIMO (M-MIMO) cryptography method of [73] was considered, although it required PCSI at both the transmitter and receiver. ...

Reference:

Artificially Time-Varying Differential MIMO for Achieving Practical Physical Layer Security

... Furthermore, to ensure the required quality of service, robust modulation schemes decrease the system throughput. Adaptive modulation has been proposed as a powerful method to maintain the desired quality of service and to maximize the transmission throughput given channel conditions [2], [3]. The basic idea of this technique is to switch between different modulation constellation sizes depending on the channel state. ...

Reference:

Impact of Uncertain Channel Estimation and Outdated Feedback on the Adaptive M-PSK Modulation

... in [2][5]. The uplink data rate, R µ , of any given microcell user has a maximum achieveable value, R * µ , determined by existing interference conditions. ...

Reference:

Uplink throughput in a single-macrocell/single-microcell CDMA system with application to data access points

... Sixth A. Roadmap of Multiple Access 1) MA in Cellular Networks: Over the last few decades, the development of MA schemes has been seen as an important factor in the evolution of cellular networks from the first-generation (1G) to 6G. As shown in Fig. 1, the MA schemes used in wireless networks, including frequency division multiple access (FDMA) in 1G systems; Time division multiple access (TDMA) [4], which is widely used in the 2G global system for mobile communications (GSM); Code division multiple access (CDMA) [5], which supports multiple users with user-specific spreading sequences within the same resource block (RB), was originally proposed by Qualcomm and is widely used in 3G; and orthogonal frequency division multiple access (OFDMA) [6], which is implemented in 4G networks by dividing the frequency and time RB into narrow subcarriers and slots. A defining feature of all MA schemes is their orthogonality, which ensures that wireless network resources, including frequency, time, and code resources, are theoretically allocated to different users. ...

Reference:

AI-Empowered Multiple Access for 6G: A Survey of Spectrum Sensing, Protocol Designs, and Optimizations

... FM HD-Radio works in FM band, but both laboratory and field tests prove it does not offer the audio quality and signal robustness performance that listeners would expect. And the low digital signal power level, which is 23 dB below the power of FM carrier, means that coverage of HD Radio is far below than that of the analogue [1]. Techniques change greatly in recent years. ...

Reference:

OFDM Parameter Design of a Digital Broadcasting System in FM Band

... Simplified structure of GSM PLMN c ETT[4]. ...

Reference:

The Pan-European Cellular System

... Orthogonal sequences are of a great practical interest for the current and future direct sequence(DS) code-division multiple-access(CDMA) systems where the orthogonality principle can be used for channels separation, e.g. [1]. However, most of the known sets of orthogonal spreading sequences possess very poor aperiodic cross-correlation characteristics, i.e. when there is any misalignment between the sequences corresponding to different users, the cross-correlation between such misaligned sequences is usually quite high, resulting in significant multi-access interference(MAI) problems where it is impossible to guarantee sequence alignment due, for example to different propagation delays. ...

Reference:

Complex Orthogonal Spreading Sequences Using Mutually Orthagonal Complimentary Sets

... In this paper, two basic scenarios are taken into account. The first scenario is composed by a GSM communication system [25,26] whose radio carriers use both the 900 MHz (GSM900) and the 1800 MHz bands (GSM1800): in this system only the voice service is considered. Therefore, as far as the traffic is concerned, the Poisson and the exponential models have been adopted for the call arrival rate and the length of each call, respectively. ...

Reference:

Sleep mode management in cellular networks: A traffic based technique enabling energy saving

... We note, furthermore, that with the advent of the emerging so-called general packet radio system known as GPRS [37] and the high-speed circuit switched data (HSCSD) [36] channel, the employment of multiple time slots per user becomes possible, which renders the system more amenable to video telephony [27], [38]. Let us consider first the 2G cellular systems represented, for example, by the global system of mobile communications known as GSM [39], [40] and its 1800-MHz carrier-frequency " up-converted " version known as the DCS 1800 system, the Pan-American IS-95 (CDMA) scheme [41], the Pan-American IS-54/IS-136 [42]–[44], and the Japanese digital cellular (JDC) arrangement [45] summarized in the left half of Table 1. These large-cell cellular systems have a speech rate of less than or equal to 13 kb/s. ...

Reference:

Interactive Cellular and Cordless Video Telephony: State-of-the-Art System Design Principles and Expected Performance

... A MS near the border of a cell can often receive radio signals from more than one BS due to the overlapped radio coverage between adjacent cells. By adopting a suitable BS selection algorithm, we can exploit the overlapped radio coverage to further enhance the system's teletraffic performance [35,36,37,38,39,40,40]. We will propose our BS selection algorithms in the latter part of Chapter 2. ...

Reference:

Teletraffic performance of microcellular networks