Digitising VHF FM sound broadcasting with DRM+ (DRM mode E)

Abstract

This paper summarizes and discusses findings on compatibility of the forthcoming DRM mode E into classical VHF FM sound broadcasting. The results are based on theoretical considerations, lab measurements, field trials and radio network planning exercises. In addition, the status of the ongoing work towards a comprehensive DRM mode E coverage study including first results hereof are given.

Residual symbol timing offset estimation for DRM+ system with cyclic delay diversity

“…In this section, simulations are performed to verify the usefulness of the proposed estimation scheme under urban and terrain obstructed channels with maximum channel delays 3 μs and 16 μs, respectively, which is widely used in analyses of FM performance [10], considering N = 213, N g = 24, N trc = 21, BW = 96KHz, and center frequency is 90 MHz [1,2]. Also, N T = 2 and |τ | ≤ N g /10 are used in our simulation.…”

“…The basic concept of the proposed STO estimation scheme is based on that the N trc TRCs are grouped into a number of subsets of pairs of two pilot subcarriers, so that every two pilots in each subset experience flat fading. Since the DRM+ system for FM broadcasting applications suffers from severe flat fading conditions [2], i.e. the channels {H t (k)} are assumed to be frequency-flat, one can effortlessly find that H(k) is periodic with a period of P H = N/δ 2 when N T = 2 and δ 1 = 0.…”

“…While DRM currently covers the broadcasting bands below 30 MHz, its consortium is extending DRM to broadcasting bands up to 120 MHz [1,2] by including the DRM robustness mode E, referred to as 'DRM+' in this paper.…”

“…for typical urban environments [2]. Thus, the major challenge in the DRM+ is to cope with severe flat fading channels.…”

Synchronization Receiver for OFDM-Based FM Broadcasting Systems

“…The standard allows the use of many existing AM transmitters, through easy modification, and provides FM-compatible sound quality. While DRM currently covers the broadcasting bands below 30 MHz, its consortium is extending the system to broadcasting bands up to 120 MHz, called DRM plus (or DRM robustness mode E) [5,6]. This mode, being designed for the FM bands, will use the same channel width as the current FM transmission.…”