I. M. Bannikov, V. A. Berezovsky, M. M. Valeev, G. K. Chazan
Achievements of modern microelectronics regarding devices of analog-digital transformation allow to approach to creation of radio receivers in a new fashion. The opportunity to introduce digital signal processing in communications centres has appeared. Earlier it is considered as a prerogative of analog devices.
In the article results of work of ONIIP on making of modern multichannel short-wave digital radio receivers in which digital processing is carried out on accepted signal frequency are submitted. Technologies of receiver construction combine opportunities of modern analog preselectors and analog-digital converters and by the dynamic characteristics do not concede to the best modern superheterodyne receiver, and by a number of parameters have significant advantages: adjacent channel selectivity is 10…15 decibels higher; overall and power consumption is a receive chain lower but reliability is higher; the opportunity of digital beamforming of short-wave phased array is rea-lized in work with narrow-band and wideband signals.
In 2010 ONIIP introduced two multichannel receivers. The basic functional device of these products is 32-channel HF receiving module with an opportunity of independent management of phase and peak characteristics of each receive chain.
Receiving module has two interfaces for connection to the local computer network corresponding to standard IEEE 802.3
with realization of a physical layer 1000BASE-T (Gigabit Ethernet). Through these interfaces the conclusion of count of output signal of receive chains on the specialized communications protocol being a derivative from RTP protocol and corresponding to the document RFC 3550 is carried out. At lower level UDP and IP protocols are used according to the documents RFC 768
and RFC 791.
The radio receiver is operated distantly from external devices by information exchange through the above mentioned interfaces for connection to the local computer network. Receive chains are operated independently of one another. Communications protocol in the receiver control is SNMP v1 protocol, corresponding to the document RFC 1157. At lower level UDP and IP protocols are used according to the documents RFC 768 and RFC 791. Set of receiver parameters related to its control is organized as MIB according to the document RFC 1155.
Use of digital multichannel radio receivers gives an opportunity of making of receiving complexes for HF frequency band with digital beamforming of a phased array that in turn allows to realize in real time an opportunity of spatial adaptation to noises in a receiving end for each receive chains individually and irrespective of others.
The suggested concept of construction of multichannel receivers becomes the key moment, capable to change the existing structure of communication centers. It might be significant decreasing of structural complexity and expenses for making the similar centers. Receivers cost per one receiver chain can be reduced by more than three times. Moreover, because of the disappeared necessity in alarm HF commutators between antennas and receivers and simplifications of physical structure of control links the profit will increase.