Evaluating the Correlation Characteristics of Arbitrary AM and FM Radio Signals for the Purpose of Navigation

The Global Positioning System (GPS) provides position estimates on the Earth at anytime, anywhere and in any weather. However, to provide robust positioning, GPS requires an unobstructed path to satellite signals. As such, GPS performance generally degrades or becomes non-existent in environments such as large urban areas. This research investigates and analyzes the correlation characteristics of arbitrary AM and FM radio signals for the purpose of navigation. Simulations are conducted with different combinations of correlation methods (`fixed\u27 or `varying\u27), modulation types (AM or FM), and signal types (song or voice). Out of the eight different variations considered, only two provided promising results for the purpose of navigation. Both the FM voice and FM song signals exhibit distinct autocorrelation peaks (i.e., 5.0 dB peak-to-sidelobe ratios) using the `fixed\u27 reference correlation method. However, results for both FM signal types revealed limited potential for navigation when using the `varying\u27 reference correlation method. All the AM signals considered yielded relatively limited potential for navigation using either correlation method

On Determining Minimal Spectrally Arbitrary Patterns

In this paper we present a new family of minimal spectrally arbitrary patterns which allow for arbitrary spectrum by using the Nilpotent-Jacobian method. The novel approach here is that we use the Intermediate Value Theorem to avoid finding an explicit nilpotent realization of the new minimal spectrally arbitrary patterns.Comment: 8 page

What If 140 Characters Can Impact Your Company’s Market Value? Tweeting Corporate Social Responsibility and Stock Prices in the Financial Sector

Many firms signal, announce, and conduct organizational activities on the prevalent Information and Communication Technology Twitter. Then, do firms financially benefit from tweeting those activities? In this paper, we focus on corporate social responsibility (CSR) signaled through tweets and examine via the event study methodology the impact of CSR tweets on organizational effectiveness measured in abnormal stock returns. Our findings show that Twitter has a broadcasting power like tradition media; tweeting CSR impacts stock prices. Managers thus may want to announce organizational activities on the more cost-effective tool Twitter, rather than on press releases. We also demonstrate that tweeting CSR less frequently is more impactful on stock prices than tweeting CSR more frequently. Managers should also take advantage of these findings; tweeting similar messages over and over again might not be as effective in getting across a particular message