Electromagnetic wave receiver front end

• US 6,895,224 B1
• Filed: 03/15/2000
• Issued: 05/17/2005
• Est. Priority Date: 03/17/1999
• Status: Expired due to Fees

• Current Assignee: Qinetiq Limited (QinetiQ Group PLC)
• Original Assignee: Qinetiq Limited (QinetiQ Group PLC)
• Inventors: Ball, Geoffrey, Munday, Paul D., Barnes, Andrew R., Moore, Mark T., Brown, Alexander L.
• Primary Examiner(s): Urban, Edward F.
• Assistant Examiner(s): LE, LANA N
• Application Number:
  US09/936,561
• Time in Patent Office: 1,889 Days
• Field of Search: 455/73, 455/78, 455/82, 455/83, 455/3.02, 455/80, 455/88, 455/194, 455/216, 455/412.2, 455/226.3, 455/226.1, 455/200.1, 455/232.1, 455/323, 455/341, 455/334, 342/118, 342/372, 375/150, 333/219
• US Class Current: 455/73
• CPC Class Codes: H03D 9/0633 mounted on a stripline circuit

Abstract

A receiver front end is provided capable of receiving electromagnetic wave signals having frequencies in the range of substantially 35 GHz to substantially 40 GHz, and having a gain of substantially 24 dB or above and a noise figure of substantially 4 dB or below, and comprising one or more multifunction monolithic microwave integrated circuits (MMICs). The receiver front end preferably has a noise figure of substantially 4 dB or below over an output signal frequency range of substantially 1 to 10 GHz, and a size in the region of 30 mm² or less. The reveiver front end may comprise a receiver MMIC, and a doubler/buffer amplifier MMIC. The receiver MMIC may comprise a low noise amplifier (3), a mixer (5), a filter (4) and an intermediate frequency amplifier (6).

Claims

1. A receiver front end for receiving electromagnetic wave signals having frequencies in the range of substantially 35 GHz to substantially 40 GHz, and having a gain of substantially 24 dB or above and a noise figure of substantially 4 dB or below, said receiver front end comprising at least one multifunction monolithic microwave integrated circuit (MMIC), said MMIC having a noise figure of substantially 4 dB or below over an output signal frequency range of substantially 1 to 10 GHz.

2. A receiver front end for receiving electromagnetic wave signals having frequencies in the range of substantially 35 GHz to substantially 40 GHz, a gain of substantially 24 dB or above, and a noise figure of substantially 4 dB or below, said front end comprising:

(a) a receiver MMIC comprising a low noise amplifier (LNA) with a noise figure less than 4 dB and a mixer for converting the frequency of a signal output from the LNA to a lower frequency mixer output signal, and

(b) a doubler/buffer amplifier MMIC,

wherein

(i) said LNA is a balanced amplifier having separate amplification sections;

(ii) each electromagnetic signal received by said LNA is split into two substantially symmetric signals, each of which is fed into said separate amplification sections; and

(iii) said mixer comprises two diodes, the signal from said LNA is fed into said diodes along with a reference signal and said diodes are adapted to multiply the signal from said LNA and said reference signal and provide an output signal having a frequency equal to the difference in frequency of the signal from said LNA and the frequency of said reference signal.

3. A receiver front end according to claim 2 wherein said mixer is a 90°

balanced mixer.

4. A receiver front end for receiving electromagnetic wave signals having frequencies in the range of substantially 35 GHz to substantially 40 GHz, a gain of substantially 24 dB or above, and a noise figure of substantially 4 dB or below, said front end comprising:

(a) a receiver MMIC comprising a low noise amplifier (LNA) with a noise figure less than 4 dB and a mixer for converting the frequency of a signal output from the LNA to a lower frequency mixer output signal; and

(b) a doubler/buffer amplifier MMIC,

wherein

(i) said LNA is a balanced amplifier having separate amplification sections;

(ii) each electromagnetic signal received by said LNA is split into two substantially symmetric signals, each of which is fed into said separate amplification sections; and

(iii) wherein said receiver MMIC comprises an IF amplifier for receiving and amplifying an IF output signal from said mixer and producing an IF output signal which is output from said receiver MMIC, and wherein said amplifier comprises a single transistor stage having gate and drain terminals, and in which a parallel resistor-inductor-capacitor feedback network is applied between said gate and drain terminals of said transistor.

5. A receiver front end package comprising:

(i) an electromagnetic wave receiver front end for receiving electromagnetic wave signals having frequencies in the range of substantially 35 GHz to substantially 40 GHz, and having a gain of substantially 24 dB or above and a noise figure of substantially 4 dB or below, said receiver front end comprising at least one multifunction monolithic microwave integrated circuit (MMIC);

(ii) power supply components for said receiver front end; and

(iii) connectors for said receiver and said power supply components,

wherein said package is double sided with separate enclosures and provides isolation of said electromagnetic wave receiver front end and said power supply components into the separate enclosures, and in which connections are made between said receiver front end and said power supply components using glass bead feedthroughs in said package.

6. A receiver front end package comprising:

(i) an electromagnetic wave receiver front end for receiving electromagnetic wave signals having frequencies in the range of substantially 35 GHz to substantially 40 GHz, and having a gain of substantially 24 dB or above and a noise figure of substantially 4 dB or below, and comprising at least one multifunction monolithic microwave integrated circuit (MMIC);

(ii) power supply components for said receiver front end; and

(iii) connectors for said receiver and said power supply components,

wherein said power supply components comprise DC biasing circuits on a circuit board, said biasing circuits containing bias sequencing and voltage regulation for all of the bias lines of said receiver front end, and

wherein said connectors are connected to the receiver front end using an airline launch technique with a better than 20 dB impedance match of said connectors with said receiver front end.

7. A receiver front end comprising:

i) a first amplifier adapted to amplify a received signal and provide an amplified signal;

ii) a filter adapted to filter said amplified signal and provide a filtered signal;

iii) a mixer adapted to take a reference signal and said filtered signal and mix them such that said mixer provides an output in a frequency range different from that of said filtered signal, so as to provide a mixed signal;

iv) a second amplifier adapted to amplify said mixed signal; and

wherein the first amplifier comprises;

a) a first Lange coupler adapted to split the signal in first and second signals such that said first and second signals have substantially 90°

phase difference;

b) a first amplification section adapted to amplify said first signal and a second amplification section adapted to amplify said second signal, said first and second amplification sections having balanced topographies, each section having first, second and third transistors and a gate and a drain bias for said transistors, said gate and drain biases being common to all the transistors;

shunt resistors associated with the gate of each transistor;

a series resistor-inductor-capacitor network in parallel with said section; and

parallel feedback being provided across said third transistor; and

c) said first and second stages having respective outputs, and a further Lange coupler being provided so as to combine said outputs of said amplification sections.

8. A receiver front end comprising:

i) a first amplifier adapted to amplify a received signal and provide an amplified signal;

ii) a filter adapted to filter said amplified signal and provide a filtered signal;

iii) a mixer adapted to take a reference signal and said filtered signal and mix them such that said mixer provides an output in a frequency range different from that of said filtered signal, so as to provide a mixed signal;

iv) a second amplifier adapted to amplify said mixed signal; and

wherein said mixer comprises;

a) a Lange coupler arranged such that both said reference signal and said filtered signal are added together and then separated into first and second signals with a phase difference of substantially 90°

; and

b) first and second diodes, each supplied with one of said phase separated first and second signals, said first and second diodes being arranged such that said first diode is in one orientation with respect to said first input signal and said second diode is in the opposite orientation with respect to said second signal;

and arranged such that a combined output signal of said first and second diodes has a frequency substantially equal to the difference between said reference and filtered signals.

9. A receiver front end comprising:

i) a first amplifier adapted to amplify a received signal and provide an amplified signal;

ii) a filter adapted to filter said amplified signal and provide a filtered signal;

iii) a mixer adapted to take a reference signal and said filtered signal and mix them such that said mixer provides an output in a frequency range different from that of said filtered signal, so as to provide a mixed signal;

iv) a second amplifier adapted to amplify said mixed signal; and

wherein said second amplifier has an output impedance and comprises a single transistor having a gate and a drain bias, a resistor-inductor-capacitor network provided between gate and drain terminals of said transistor and a resistor-capacitor network adapted to match said input impedance of the second amplifier to that required by said mixer for proper operation thereof.

10. A receiver front end comprising:

i) a first amplifier adapted to amplify a received signal and provide an amplified signal;

ii) a filter adapted to filter said amplified signal and provide a filtered signal;

iii) a mixer adapted to take a reference signal and said filtered signal and mix them such that said mixer provides an output in a frequency range different from that of said filtered signal, so as to provide a mixed signal;

iv) a second amplifier adapted to amplify said mixed signal; and

wherein the first amplifier comprises;

a) a first Lange coupler adapted to split the signal in first and second signals such that said first and second signals have substantially 90°

phase difference;

b) a first amplification section adapted to amplify said first signal and a second amplification section adapted to amplify said second signal, said first and second amplification sections having balanced topographies, each section having first, second and third transistors and a gate and a drain bias for said transistors, said gate and drain biases being common to all the transistors;

shunt resistors associated with the gate of each transistor;

a series resistor-inductor-capacitor network in parallel with said section, and parallel feedback being provided across said third transistor; and

c) said first and second stages having respective outputs, and a further Lange coupler being provided so as to combine said outputs of said amplification sections; and

wherein said mixer comprises;

a) a Lange coupler arranged such that both said reference signal and said filtered signal are added together and then separated into first and second signals with a phase difference of substantially 90°

; and

b) first and second diodes, each supplied with one of said phase separated first and second signals, said first and second diodes being arranged such that said first diode is in one orientation with respect to said first input signal and said second diode is in the opposite orientation with respect to said second signal;

and arranged such that a combined output signal of said first and second diodes has a frequency substantially equal to the difference between said reference and filtered signals; and

wherein said filter is a distributed transmission line filter, arranged in a serpentine fashion, containing quarter wave coupled elements, said filter being adapted to suppress a sideband of the output of said first amplifier;

wherein said second amplifier has an output impedance and comprises a single transistor having a gate and a drain bias, a resistor-inductor-capacitor network provided between gate and drain terminals of said transistor and a resistor-capacitor network adapted to match said input impedance of the second amplifier to that required by said mixer for proper thereof; and

wherein said reference signal is generated by means of a local oscillator, the output of which is sued to supply a frequency doubler, the output of said doubler being passed through an amplifier before being used as said reference signal.