Four‐bit reconfigurable discriminator for frequency identification receivers: A building block approach

Abstract

This paper presents a building block approach to design a reconfigurable discriminator (RD), which is the core circuit in frequency identification receivers. The RD is used to identify an unknown signal; the output of the circuit determines a frequency subband where the unknown signal falls into. The proposed building block design approach is scalable and can be used to produce any multibit RD. This design approach can be used to produce RD circuits with more or less resolution for a fixed band of operation, according to the number of bits used for a given design. The building block approach is demonstrated through the design of a 4‐bit RD. This design is a two‐port device that provides a series readout and can produce 4 bits for frequency identification. The device operates from 1 to 4 GHz, implemented by microstrip lines and PIN diode switches. Simulated and measured responses are in agreement.

Frequency and angular estimations of detected microwave source using unmanned aerial vehicles

“…The unknown signal can be identified after it passes through frequency discriminators [6][7][8][9][10]. The signal is identified by a frequency sub-band defined by the circuit, where the unknown signal is allocated [8,10]. The device frequency band of operation is divided in frequency sub-bands; the number of sub-bands used for frequency identification depends on the number of bits of the design.…”

“…A four bit RFM circuit is shown in fig. 4, the circuit switches between four frequency discriminators using PIN diode based switches, providing one bit at a time at the output [8]. A two bit RFM circuit is described in [10].…”

“…To identify the frequency of the unknown detected signal, the frequency band to be scanned is divided in sub-bands by using frequency discriminators [6][7]. The number of subbands of the system is determined by the number of bits used in the design [8]. This paper describes the circuits required to identify the incoming direction and the frequency of the unknown signal.…”

Review of microwave frequency measurement circuits

“…Fixed designs have a predefined number of frequency discriminators with an associated resolution and frequency of operation. They can be implemented using delay lines [6][7][8][9][10][11][12][13][14][15][16][17][18][19] using planar or coaxial transmission lines, or filters [20][21][22][23][24][25][26][27][28][29]. Discriminators based on filters and delay lines are designed to produce a frequency response associated with Gray's code, obtained after the ACD stage [30].…”

Microwave Interference Techniques for Frequency Measurement and Filters

“…Microwave interference is useful to design microwave devices with filtering properties, such as interferometers for frequency measurement applications [1][2][3][4], wide-band [5,6] and dual-band [7] bandpass filters among others. The core part of these devices is the interferometer section.…”